U.S. patent application number 15/964279 was filed with the patent office on 2019-10-31 for determining estimated remaining use of brake assembly by transceiver.
This patent application is currently assigned to Honeywell International Inc.. The applicant listed for this patent is Honeywell International Inc.. Invention is credited to Pradeep Huncha, Raghavendra Muniraju, Vedavyas Rallabandi, Shajahan Sheriff.
Application Number | 20190329755 15/964279 |
Document ID | / |
Family ID | 68292076 |
Filed Date | 2019-10-31 |
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United States Patent
Application |
20190329755 |
Kind Code |
A1 |
Sheriff; Shajahan ; et
al. |
October 31, 2019 |
DETERMINING ESTIMATED REMAINING USE OF BRAKE ASSEMBLY BY
TRANSCEIVER
Abstract
In some examples, device is configured to determine an estimated
remaining use of a brake assembly. The device includes a
transceiver configured to transmit a signal towards a wear pin in
the brake assembly at a first time. The transceiver is also
configured to receive a reflection of the signal from the wear pin
at a second time. The device further includes processing circuitry
configured to determine a difference of the first time and the
second time. The processing circuitry is also configured to
determine the estimated remaining use of the brake assembly based
on the difference of the first time and the second time.
Inventors: |
Sheriff; Shajahan; (Madurai,
IN) ; Rallabandi; Vedavyas; (Bangalore, IN) ;
Huncha; Pradeep; (Bangalore, IN) ; Muniraju;
Raghavendra; (Bangalore, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Honeywell International Inc. |
Morris Plains |
NJ |
US |
|
|
Assignee: |
Honeywell International
Inc.
Morris Plains
NJ
|
Family ID: |
68292076 |
Appl. No.: |
15/964279 |
Filed: |
April 27, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16D 66/028 20130101;
G01B 17/00 20130101; B60T 17/221 20130101; G01B 11/0691 20130101;
G01B 11/026 20130101 |
International
Class: |
B60T 17/22 20060101
B60T017/22; G01B 11/06 20060101 G01B011/06 |
Claims
1. A device configured to determine an estimated remaining use of a
brake assembly, the device comprising: an attachment element
configured to attach the device to a brake carrier of the brake
assembly without the device contacting a wear pin in the brake
assembly; a transceiver configured to: transmit a signal towards
the wear pin at a first time, wherein the wear pin moves relative
to the brake carrier as a brake lining of the brake assembly wears
down over time; and receive a reflection of the signal from the
wear pin at a second time; and processing circuitry configured to:
determine a difference of the first time and the second time; and
determine the estimated remaining use of the brake assembly based
on the difference of the first time and the second time.
2. (canceled)
3. The device of claim 1, wherein the processing circuitry is
further configured to determine a distance to the wear pin based on
the difference of the first time and the second time, and wherein
the processing circuitry is configured to determine the estimated
remaining use of the brake assembly based on the length of the wear
pin.
4. The device of claim 1, wherein the processing circuitry is
further configured to: determine whether the estimated remaining
use of the brake assembly is less than a threshold amount; and
generate an alert in response to determining that the estimated
remaining use of the brake assembly is less than the threshold
amount.
5. The device of claim 4, further comprising a communication module
configured to transmit the alert to an external device.
6. The device of claim 1, further comprising a communication module
configured to transmit an indication of the estimated remaining use
of the brake assembly to an external device.
7. The device of claim 1, wherein the signal is a first signal,
wherein the reflection is a first reflection, and wherein the
estimated remaining use of the brake assembly is a first estimated
remaining use of the brake assembly, and wherein the transceiver is
further configured to: transmit a second signal towards the wear
pin at a third time; and receive a second reflection of the second
signal from the wear pin at a fourth time, wherein the processing
circuitry is further configured to: determine a difference of the
third time and the fourth time; and determine a second estimated
remaining use of the brake assembly based on the difference of the
third time and the fourth time.
8. The device of claim 7, wherein the processing circuitry is
further configured to: determine a number of braking events between
the first time and the third time; and determine a rate of wear
based on the first estimated remaining use of the brake assembly,
the second estimated remaining use of the brake assembly, and the
number of braking events.
9. The device of claim 8, wherein the processing circuitry is
further configured to: determine that the rate of wear exceeds a
threshold rate; and generate an alert in response to determining
that the rate of wear exceeds the threshold rate.
10. The device of claim 8, further comprising a memory device,
wherein the processing circuitry is further configured to: store
the first estimated remaining use of the brake assembly to the
memory device; and store the second estimated remaining use of the
brake assembly to the memory device.
11. The device of claim 1, further comprising a memory device
configured to store a mapping of times to estimates of remaining
use of the brake assembly, wherein the processing circuitry is
further configured to update the mapping based on the difference of
the first time and the second time.
12. The device of claim 1, wherein the processing circuitry is
configured to determine the estimated remaining use of the brake
assembly by at least determining a distance between the transceiver
and the wear pin based on a difference of the first time and the
second time.
13. (canceled)
14. The device of claim 1, wherein the transceiver comprises a
laser.
15. A method comprising: causing a transceiver attached to a brake
carrier of a brake assembly without the transceiver contacting a
wear pin in the brake assembly to transmit a signal towards the
wear pin in the brake assembly at a first time, wherein the wear
pin moves relative to the brake carrier as a brake lining of the
brake assembly wears down over time; causing the transceiver to
receive a reflection of the signal from the wear pin at a second
time; determining a difference of the first time and the second
time; and determining an estimated remaining use of a brake
assembly based on the difference of the first time and the second
time.
16. The method of claim 15, further comprising: determining, in a
first instance, that the estimated remaining use of the brake
assembly is less than a threshold amount; generating an alert in
response to determining that the estimated remaining use of the
brake assembly is less than the threshold amount; causing a
communication module to transmit the alert to an external device;
determining, in a second instance, that the estimated remaining use
of the brake assembly is greater than the threshold amount; and
refrain from generating the alert in response to determining that
the estimated remaining use of the brake assembly is greater than
the threshold amount.
17. The method of claim 15, further comprising causing a
communication module to transmit an indication of the estimated
remaining use of the brake assembly to an external device.
18. The method of claim 15, wherein the signal is a first signal,
wherein the reflection is a first reflection, and wherein the
estimated remaining use of the brake assembly is a first estimated
remaining use of the brake assembly, the method further comprising:
causing the transceiver to transmit a second signal towards the
wear pin at a third time; causing the transceiver to receive a
second reflection of the second signal from the wear pin at a
fourth time; determining a difference of the third time and the
fourth time; determining a second estimated remaining use of the
brake assembly based on a difference of the third time and the
fourth time; determining a number of braking events between the
first time and the third time; and determining a rate of wear based
on the first estimated remaining use of the brake assembly, the
second estimated remaining use of the brake assembly, and the
number of braking events.
19. The method of claim 15, further comprising: determining a
distance between the transceiver and the wear pin based on a
difference of the first time and the second time; and determining a
length of the wear pin based on the distance between the
transceiver and the wear pin, wherein determining the remaining use
on the brake assembly is based on the length of the wear pin.
20. (canceled)
21. A device configured to determine a rate of wear for a brake
assembly, the device comprising: a transceiver configured to:
transmit a first signal towards a wear pin in the brake assembly at
a first time; receive a first reflection of the first signal from
the wear pin at a second time; transmit a second signal towards the
wear pin at a third time; and receive a second reflection of the
second signal from the wear pin at a fourth time; and processing
circuitry configured to: determine a first estimated remaining use
of the brake assembly based on a difference of the first time and
the second time; determine a second estimated remaining use of the
brake assembly based on a difference of the third time and the
fourth time; determine a number of braking events between the first
time and the third time; and determine the rate of wear based on
the first estimated remaining use of the brake assembly, the second
estimated remaining use of the brake assembly, and the number of
braking events.
22. The device of claim 21, wherein the processing circuitry is
further configured to determine a distance to the wear pin based on
the difference of the first time and the second time, and wherein
the processing circuitry is configured to determine the estimated
remaining use of the brake assembly based on the length of the wear
pin.
23. The device of claim 21, wherein the processing circuitry is
configured to determine the estimated remaining use of the brake
assembly by at least determining a distance between the transceiver
and the wear pin based on a difference of the first time and the
second time.
Description
TECHNICAL FIELD
[0001] The disclosure relates to vehicle brake systems.
BACKGROUND
[0002] During periodic maintenance, the amount of wear on a
vehicle's braking assembly is manually assessed by a maintenance
technician. On an aircraft, for example, the remaining life of the
braking assembly is determined by observing the length of a wear
indicator pin, also known as a wear pin.
SUMMARY
[0003] In general, this disclosure describes systems and methods
for automated measurements of the remaining use of a vehicle's
braking assembly. The measurement of the remaining use may indicate
the number of remaining braking events (e.g., aircraft landings)
with optimal braking without replacing the braking lining. A
transceiver connected to processing circuitry can determine an
estimate of the remaining use. The transceiver sends signals and
receives reflections of the signals. The processing circuitry
determines an estimated remaining use of the braking assembly based
on the time of transmission and the time of receipt by the
transceiver. The difference between the time of transmission and
the time of receipt may also indicates, or relates to, the distance
between the transceiver and the wear pin and the length of the wear
pin, which the processing circuitry can use to estimate a remaining
use or a remaining life for the braking assembly.
[0004] In some examples, a device is configured to determine an
estimated remaining use of a brake assembly. The device includes a
transceiver configured to transmit a signal towards a wear pin in
the brake assembly at a first time and receive a reflection of the
signal from the wear pin at a second time. The device also includes
processing circuitry configured to determine a difference of the
first time and the second time and determine the estimated
remaining use of the brake assembly based on the difference of the
first time and the second time.
[0005] In some examples, a method includes causing a transceiver to
transmit a signal towards a wear pin in a brake assembly at a first
time and causing the transceiver to receive a reflection of the
signal from the wear pin at a second time. The method also includes
determining a difference of the first time and the second time and
determining an estimated remaining use of a brake assembly based on
the difference of the first time and the second time.
[0006] In some examples, a device includes a computer-readable
medium having executable instructions stored thereon, wherein the
instructions are configured to be executable by one or more
processors for causing the one or more processors to cause a
transceiver to transmit a signal towards a wear pin in a brake
assembly at a first time. The instructions are also configured to
cause the one or more processors to cause the transceiver to
receive a reflection of the signal from the wear pin at a second
time. The instructions are further configured to cause the one or
more processors to determine a difference of the first time and the
second time and determining an estimated remaining use of a brake
assembly based on the difference of the first time and the second
time.
BRIEF DESCRIPTION OF DRAWINGS
[0007] FIG. 1 is a conceptual block diagram depicting a device
configured to determine an estimated remaining use of a brake
assembly.
[0008] FIG. 2 is a conceptual block diagram of an example device of
FIG. 1.
[0009] FIG. 3 is a diagram depicting an example of the device of
FIG. 1 attached to a brake carrier.
[0010] FIGS. 4A and 4B are perspective views of examples of a
device and a wear pin.
[0011] FIG. 5 is a conceptual block diagram illustrating a system
with data analytics and cloud applications.
[0012] FIG. 6 shows a flowchart for example techniques for
determining an estimated remaining use of a brake assembly, in
accordance with some examples of this disclosure.
DETAILED DESCRIPTION
[0013] This disclosure describes techniques for determining an
estimated remaining use of a brake assembly based on signals
transmitted towards a wear pin (e.g., a "wear indicator" or a "wear
indicator pin") in the brake assembly. In some examples, a device
includes a transceiver configured to transmit a signal and receive
a reflection of the signal. The device also includes processing
circuitry configured to determine the time difference between the
transmission and receipt of the signal. The processing circuitry is
configured to determine an estimated remaining use of the brake
assembly based on the time difference. In some examples, the
processing circuitry is configured to determine the distance
between the transceiver and the wear pin based on the time
difference and determine the length of the wear pin based on the
distance between the transceiver and the wear pin. The processing
circuitry may be configured to determine the estimated remaining
use based on an estimated rate of wear for a brake lining of the
braking assembly.
[0014] The techniques described herein may be described with
respect to determining a length of a wear pin with the
understanding that the length of the wear pin corresponds to the
amount of use or estimated life of the brake assembly. It should be
understood however that when implemented by processing circuitry,
the processing circuitry does not necessarily need a length and may
just map a time to the estimated life of the brake assembly. The
mapping, which may be stored to a memory device, can associate
times and estimated remaining uses for the brake assembly. The
mapping can be based on an equation, a lookup table, or a data
structure and may include data such as times, distances, lengths,
remaining uses, and wear rates.
[0015] The device can be installed in an existing brake assembly as
a retrofit sensor (e.g., an after-market product), or the device
can be built into a new brake assembly. In some examples, the
device is installed such that the transceiver does not touch the
wear pin. The processing circuitry may be configured to determine
and track the length of the wear pin as the length declines over
the life of the brake assembly. The processing circuitry may also
be configured to output data indicating the length(s) of the wear
pin and/or estimate(s) of the remaining life of the brake
assembly.
[0016] Other methods of assessing the length of a brake assembly's
wear indicator pin are not proactive, as they require a second
person in the cockpit of the aircraft to apply the brakes or to set
the parking brake before the pin can be observed. Thus, the
techniques of this disclosure may enable a technician to more
easily determine the length of the wear pin. Additionally, because
the brakes are replaced when a technician observes that the wear
pin is flush or nearly flush with the surface of the brake carrier,
the brakes may not be used to the fullest extent of their remaining
lifespan. A device of this disclosure may output indications of the
distance between the transceiver and the wear pin, the length of
the wear pin, the remaining use of the braking assembly, an alert,
and/or other data determined by the processing circuitry. The
device may generate more accurate notifications of the remaining
life of a brake assembly, as compared to a caliper measurement,
allowing maintenance workers to change the brakes at an appropriate
time. Accurate notifications can allow maintenance workers to get
all of the useful life out of the brakes, without the risk that
replacement will be postponed too long. In some examples, one-tenth
of one inch of length on the wear pin may last approximately one
hundred braking events.
[0017] A monolithic construction of the proposed device can be
placed on top of the brake system's carrier, surrounding the brake
wear pin indicator. Opposite the brake wear pin, a laser
transmitter and receiver can be installed. The laser transmitter
and receiver may not physically contact the brake wear pin in order
to conduct a measurement. A transceiver sends pulsed signals on the
transmitter and receives the signals on the receiver. Processing
circuitry may then measure the time taken for the light to travel
from transmitter to receiver. Using the known speed of light, or
any other applicable speed of the signals, the processing circuitry
can determine the distance between the laser unit and the tip of
the brake wear pin. The processing circuitry can interpret this
information to show the brake wear pin length. Using a molding
manufacturing process, the proposed device can be constructed so
that the device can withstand the harsh environment conditions of
an aircraft wheel. This method of measuring the length of the wear
pin may not require human intervention because the processing
circuitry may be configured to output an indication of the
estimated remaining use and/or the length of the wear pin. The
processing circuitry can measure and log data automatically and
more frequently than other brake wear devices. This device may
enable a vehicle operator, through a computing system located in an
avionics bay, to apply algorithms on the measured data and predict
the wear remaining on a brake assembly and plan for maintenance
more efficiently.
[0018] FIG. 1 is a conceptual block diagram depicting a device 100
configured to determine an estimated remaining use of a brake
assembly 170. Device 100 includes transceiver 110, processing
circuitry 120, and memory device 130. Device 100 is physically
attached to brake assembly 170 of a vehicle, such as an aircraft, a
helicopter or a weather balloon, a space vehicle such as a
satellite or spaceship, a land vehicle such as an automobile, a
water vehicle such as a ship or a submarine, a manned vehicle, an
unmanned vehicle such as a drone, a remote-control vehicle, or any
suitable vehicle without any pilot or crew on board. Brake assembly
170 includes an external brake carrier, a wear indicator pin 160,
plate 180, and brake lining 190.
[0019] Device 100 may be attached to brake assembly 170 by
mounting, gluing, taping, soldering, and/or any other attaching
technique. In some examples, transceiver 110 is attached to brake
assembly 170 such that transceiver 110 does not move. Therefore, as
the length of wear indicator pin 160 decreases, the difference in
time between transmission of signal 140 and receipt of reflected
signal 150 may increase, indicating an increased distance between
transceiver 110 and wear indicator pin 160. The increased distance
may indicate a reduction in the length of wear indicator pin 160,
which indicates the remaining use of brake assembly 170.
[0020] Transceiver 110 includes both transmitting and receiving
capabilities and can be directed toward an exposed tip of wear
indicator pin 160. A transmitting component of transceiver 110 is
capable of emitting a signal, such as transmitted signal 140,
toward the tip of wear indicator pin 160. A receiving component of
transceiver 110 is capable of sensing or detecting a signal, such
as reflected signal 150, returning from wear indicator pin 160.
Transceiver 110 may include a laser, an ultrasonic sensor, or any
other sensor capable of sending and receiving signals.
[0021] Transmitted signal 140 may consist of an electromagnetic
wave of a specific frequency, for example, light emitted from a
laser or a radio-frequency (RF) wave. Transmitted signal 140
reflects off of the tip or surface of wear indicator pin 160,
becoming reflected signal 150 having the same or similar frequency
as transmitted signal 140. Transceiver 110 may transmit signal 140
at a first time and receive reflected signal 150 at a second time.
For example, the first time and the second time may be one
millisecond apart. The difference between the first time and the
second time, along with the speed of signals 140 and 150 may
indicate the distance between transceiver 110 and wear pin 160.
[0022] Processing circuitry 120 is configured to determine an
estimated remaining use of brake assembly 170. Processing circuitry
120 may be configured to determine the estimated remaining use
based directly on the time difference of signals 140 and 150, or
processing circuitry 120 may first determine the length of wear
indicator pin 160. Processing circuitry 120 can determine the
length of wear indicator pin 160 based on the time difference and
determine the remaining use of brake assembly 170 based on the
length of wear indicator pin 160. Processing circuitry 120 may
divide the length by an estimate of the wear (e.g., reduction in
length) per braking event to determine the remaining use.
Processing circuitry 120 can use the specifications for brake
assembly 170 to determine the estimate of wear per braking event
(e.g., rate of wear). Alternatively or additionally, processing
circuitry 110 can use measurements of the length of wear indicator
pin 160, along with the number of braking events between
measurements, to determine the estimate of wear per braking
event.
[0023] Processing circuitry 120 is configured to cause transceiver
110 to emit transmitted signal 140, and to subsequently receive
from transceiver 110 a set of time data indicative of the time at
which transceiver 110 received reflected signal 150. Processing
circuitry 120 is further configured to determine a difference in
time between the transmission of transmitted signal 140 and receipt
of reflected signal 150, and to use this time difference along with
a known signal velocity to determine the distance travelled by
transmitted signal 140. Using this distance, processing circuitry
120 may be configured to determine the remaining length of wear
indicator pin 160 by comparing the current distance measurement to
an initial or previous distance or length. Processing circuitry 120
may also be configured to transmit the determined current length of
wear indicator pin 160, along with a timestamp indicative of the
time at which the length was measured, to be stored within memory
device 130.
[0024] Processing circuitry 120 may further be configured to
retrieve from memory device 130 a previous set of wear pin length
and time data and use the data in conjunction with a current
measurement in order to determine a rate of change of the length of
wear pin 160 during the time between which the different
measurements were conducted. Processing circuitry 120 may then
transmit the rate of change data to be stored in memory device 130
along with the length and time data. Processing circuitry 120 may
determine if the length of the wear pin is less than a threshold
length and generate an alert in response to determining that the
length of the wear pin is less than the threshold length. Such an
alert may be an audio alert, such as a recorded verbal message or a
tone, or alternatively or additionally, a visual alert, such as a
displayed phrase, message, symbol, or color.
[0025] In some examples, processing circuitry 120 may perform data
analysis on the data indicating the length of wear indicator pin
160. For example, processing circuitry 120 may use data indicating
the number of braking events, the weather conditions during each
braking event, the vehicle operator during each braking event, the
type of surface for each braking event (asphalt, concrete, etc.),
and/or any other data stored to memory device 130. Processing
circuitry 120 may determine metrics such as the rate of wear and
the estimated remaining life of wear indicator pin 160. Processing
circuitry 120 may also determine when and whether to generate
alerts regarding the status of wear indicator pin 160 and/or brake
assembly 170. Alternatively or additionally, processing circuitry
120 may output the data to an external computing system, such as
the avionics bay of an aircraft, to perform the data analysis on
data relating to wear indicator pin 160 and/or brake assembly
170.
[0026] Memory device 130 is a non-transitory computer-readable
medium capable of storing information indicative of the length of
wear indicator pin 160 along with a timestamp indicating the time
at which the measurement was made. Memory device 130 may be further
configured to store multiple sets of length and time data, as well
as rates of change of the length of wear pin 160 between subsequent
measurements. Memory device 130 may also store threshold lengths
and threshold distances that processing circuitry 120 may use to
determine if wear pin 160 is approaching an end of useful life. In
some examples, memory device 130 stores data relating to braking
events, such as a measurement conducted when the brakes are
applied, and weather or climate conditions.
[0027] Processing circuitry 120 may be configured to determine the
estimated remaining use of brake assembly 170 directly based on the
time difference of signals 140 and 150, for example, based on a
mapping of time differences to remaining-use estimates stored to
memory device 130. The mapping may take the form a data structure
such as an array or a lookup table that associates estimated
remaining uses with time differences. Processing circuitry 120 may
use the mapping stored to memory device 130 to directly determine
the estimated remaining use of brake assembly 170, or processing
circuitry 120 may first determine the distance between transceiver
110 and wear indicator pin 160. Processing circuitry 120 may be
configured to update the mapping stored to memory device 130 by
storing the new value of the time difference and the new estimated
remaining use of brake assembly 170 to memory device 130.
[0028] Device 100 may also include a communication module (e.g.,
communication module 240 shown in FIG. 2) configured to transmit
data to an external computing system. The communication module may
transmit data through a wired connection or a wireless connection
to the external computing system. The transmitted data may indicate
the estimated remaining use of brake assembly 170, the length of
the wear, the rate of change of the length of the wear pin, and/or
any other relevant data.
[0029] Wear indicator pin 160 is a component whose exposed length
represents the remaining lifespan of brake assembly 170 of a
vehicle. Wear indicator pin 160 is also referred to herein as "wear
pin 160." In some examples, when the tip of wear indicator pin 160
is flush with the brake carrier, the vehicle's brakes may need
replacement due to excessive wear. Wear indicator pin 160 may have
any suitable shape, such as a cylinder or a rectangle, where the
length of wear indicator pin 160 may decrease over time. As a
cylinder, wear indicator pin 160 may have a radius of a few
millimeters. Wear indicator pin 160 can also include a material
layer, a coating, and/or a covering that indicates the wear of
brake assembly 170.
[0030] Brake assembly 170 may include braking elements for slowing
the speed of rotation of vehicle wheels, such as automobile wheels
or aircraft landing gear. Brake assembly 170 may be mounted to or
built in to the wheels. Device 100 may be mounted to a part of
brake assembly 170, such as a brake carrier. Brake assembly 170 may
also be referred to herein as a "braking assembly" or as a "braking
system." As used herein, the term "the remaining use of brake
assembly 170" may refer to the remaining use of brake lining
190.
[0031] Wear indicator pin 160 is mounted on plate 180 (e.g., by a
rivet), which holds brake lining 190 on the other side of plate
190. Plate 180 may include metal material. Pressure plate 320 shown
in FIG. 3 is an example of plate 180. Plate 180 can be attached to
one or more pads of brake lining 190 that may include steel or
carbon. When the brakes are applied during a braking event, a
stationary hydraulic system can push or displace plate 180 against
brake lining 190 thereby generating friction between the stationary
pads of brake lining 190 and the rotating component, such as a
wheel disc. The friction between the pads of brake lining 190 and
the rotating component causes the rotation of the wheel to decline.
Brake lining 190 may be the active portion of braking assembly that
wears down over time due to braking events. Brake lining 190 may
also be referred to as "a brake shoe" or "a brake pad."
[0032] In accordance with the techniques of this disclosure,
processing circuitry 120 may determine the estimated remaining use
of brake assembly 170 based on the time of transmission of signal
140 and the time of receipt of reflected signal 150. Device 100 may
perform a measurement of the estimated remaining use of brake
assembly 170 automatically (e.g., without a human operator). For
example, a measurement of the estimated remaining use of brake
assembly 170 may occur when the brakes of brake assembly 170 are
applied. Processing circuitry 120 may be configured to determine
when the brakes are applied and to cause, without human
intervention, transceiver 110 to transmit and receive signals 140
and 150 when the brakes are applied.
[0033] The techniques of this disclosure may be especially useful
for after-market devices that can be installed on existing brake
assemblies. An after-market device may be installed on a brake
carrier such that the device does not contact wear indicator pin
160.
[0034] FIG. 2 is a conceptual block diagram of an example device of
FIG. 1. Device 200 includes transceiver 210, processing circuitry
220, timer 222, memory device 230, communication module 240,
attachment element 250, and power supply 260. Device 200 is an
example of device 100 shown in FIG. 1. Device 200 is physically
attached to a brake assembly of a vehicle, such as an aircraft, a
helicopter or a weather balloon, a space vehicle such as a
satellite or spaceship, a land vehicle such as an automobile, a
water vehicle such as a ship or a submarine, a manned vehicle, an
unmanned vehicle such as a drone, a remote-control vehicle, or any
suitable vehicle without any pilot or crew on board.
[0035] Transceiver 210 includes both transmitting and receiving
capabilities and can be directed toward an exposed tip or surface
of the brake assembly's wear indicator pin. Transceiver 210 is an
example of transceiver 110. A transmitting component of transceiver
210 is capable of emitting a signal toward the tip or surface of
the wear indicator pin. A receiving component of transceiver 210 is
capable of sensing or detecting a reflected signal returning from
the wear indicator pin. Transceiver 210 may incorporate a laser, an
ultrasonic sensor, or any other sensor capable of sending and
receiving signals.
[0036] Processing circuitry 220 is configured to determine the
length of a brake assembly's wear indicator pin. Processing
circuitry 220 is configured to cause transceiver 210 to emit a
signal, and to subsequently receive from transceiver 210 a
reflection of that signal. Processing circuitry 220 can determine
the remaining use based on the length of the wear pin and a rate of
wear stored to memory device 230. Processing circuitry 220 may
determine the remaining use in terms of the number of braking
events.
[0037] Timer 222 is configured to transmit to processing circuitry
220 a first timestamp indicative of the time at which the signal
was emitted. Timer 222 is further configured to transmit to
processing circuitry a second timestamp indicative of the time at
which the reflected signal was received or detected. In some
examples, timer 222 may include a counter configured to increment a
number stored to a register based on a clock signal. Processing
circuitry 220 may be configured to reset timer 222 at the time that
transceiver 210 transmits a signal towards a wear pin. Processing
circuitry 220 may check the timer value when transceiver 210
receives a reflected signal to determine the time at which the
reflected signal is received.
[0038] Processing circuitry 220 is further configured to determine
a difference in time between the first timestamp, indicative of the
transmitted signal, and the second timestamp, indicative of the
reflected signal, and to use this time difference along with a
known signal velocity to determine the distance travelled by the
transmitted signal. Using this determined distance, processing
circuitry 220 may be configured to determine the remaining length
of the wear indicator pin by comparing the current distance
measurement to an initial or previous distance or length
measurement. Processing circuitry 220 may also be configured to
transmit the determined current length of the wear indicator pin,
along with a timestamp indicative of the time at which the current
length measurement was made, to be stored within memory device
230.
[0039] Processing circuitry 220 may further be configured to
retrieve from memory device 230 a previous set of estimated
remaining use data and use the data in conjunction with a current
measurement in order to determine a rate of change of the estimated
remaining use during the time between which the different
measurements were conducted. Processing circuitry 220 may then
transmit the rate-of-change data to be stored in memory device 230
along with the current estimated remaining use and time data.
Processing circuitry 220 may determine whether the estimated
remaining use is less than a threshold amount and/or the length of
the wear pin is less than a threshold length stored to memory
device 230, and processing circuitry 220 may generate an alert in
response to determining that the estimated remaining use is less
than a threshold amount and/or the length of the wear pin is less
than the threshold length. Processing circuitry 220 may cause
communication module 240 to transmit the alert to an external
device. Processing circuitry 220 may also be configured to
determine that the estimated remaining use is less than a threshold
amount and/or the length of the wear pin is greater than the
threshold length and refrain from generating the alert in response
to determining that the estimated remaining use is less than a
threshold amount and/or the length of the wear pin is greater than
the threshold length. In some examples, a determination that the
estimated remaining use is less than a threshold amount and/or the
length is less than the threshold length includes a determination
that the estimated remaining use and/or the length is less than or
equal than the threshold amount or the threshold length.
[0040] In some examples, processing circuitry 220 may perform data
analysis on the data indicating the length of the wear indicator
pin. For example, processing circuitry 220 may use data indicating
the number of braking events, the weather conditions during each
braking event, the vehicle operator during each braking event, the
type of surface for each braking event (asphalt, concrete, etc.),
and/or any other data stored to memory device 230. Processing
circuitry 220 may determine metrics such as the rate of wear and
the estimated remaining life of the wear indicator pin. Processing
circuitry 220 may also determine whether and when to generate
alerts regarding the status of the wear indicator pin and/or the
vehicle's brake assembly.
[0041] Processing circuitry 220 may be further configured to cause
device 200 to perform a measurement of the length of the wear
indicator pin automatically (e.g., without a human operator). For
example, a measurement of the length of the wear indicator pin may
occur automatically when the brakes of the brake assembly are
applied. Processing circuitry 220 may be configured to determine
when the brakes are applied and to cause, without human
intervention, transceiver 210 to transmit and receive signals when
the brakes are applied.
[0042] Memory device 230 is a non-transitory computer-readable
medium capable of storing information indicative of the length of
wear indicator pin along with a timestamp indicating the time at
which the measurement was made. Memory device 230 may be further
configured to store multiple sets of length and time data, as well
as rates of change of the length of wear pin between subsequent
measurements. Memory device 230 may also store threshold amounts,
threshold lengths, and threshold distances that processing
circuitry 220 may use to determine if the wear indicator pin is
approaching the end of its useful life. In some examples, memory
device 230 stores data relating to braking events and weather
conditions. Memory device 230 may also store reference data
indicating an initial remaining use and/or an initial length of the
wear pin or a distance between transceiver 210 and a brake carrier.
In some examples, it may be acceptable for the surface of the wear
pin to reach the edge of the brake carrier, or there may a
particular distance from the edge of the brake carrier at which the
wear pin indicates that the brakes should be replaced.
[0043] Communication module 240 may output any or all of the
collected measurements, determined data, and/or generated alerts to
an external receiver (e.g., an external device). An external
receiver may consist of a computing system, such as the avionics
bay of an aircraft, to perform data analysis on data relating to
the wear indicator pin and/or the vehicle's brake assembly.
Alternatively or additionally, communication module 240 may output
the data or generated alerts to a display device, to be observed
by, for example, a pilot, driver, or mechanic. Communication module
240 may consist of a hard-wired system, such as wires or
fiber-optic cable and/or a wireless communication system, such as
Wi-Fi, Bluetooth, radio-frequency identification (RFID), near-field
communication (NFC), or any other electromagnetic signal.
[0044] Attachment element 250 connects device 200 to the external
carrier of a vehicle's brake assembly, such that transceiver 210 is
not capable of moving with respect to the external carrier. The
connection between device 200 and the brake assembly may be a rigid
connection or there may be some flexibility to the connection.
Attachment element 250 may be connected to the brake assembly by
any appropriately permanent means, for example, by mounting,
screwing, welding, gluing, taping, soldering, and/or any other
attaching technique. In some examples, attachment element 250
includes an electro-mechanical element, such as a solenoid
configured to provide attachment means in response to an electrical
current.
[0045] There are different types of brake systems available
depending on the type of aircraft, ranging from single disc brakes
to segmented rotor brakes and carbon brakes. For simple brake
systems, wear determination can include visually inspecting the
brake disc. For complex brake systems, the brake assembly may
include a wear indicator pin to help device 200 to determine the
brake wear. The brake wear pin protrudes out via brake carrier or a
carrier element. Device 200 can be mounted on the brake carrier or
the carrier element rigidly such that the device 200 does not move
and transceiver 210 is positioned directly above the wear pin and
configured to transmit and receive the return signal.
[0046] Power supply 260 delivers electrical power to drive device
200. Power supply 260 may consist of an external battery, such as a
lithium-ion battery or any lithium-based chemistry battery.
Alternatively, power supply 260 may consist of an existing power
source that is delivering power to the rest of the wheel-and-brake
assembly. Alternatively, power supply 260 may consist of a system
for passively harvesting energy emitted by the rest of the brake
assembly. An example of such a passive energy source may include
thermo-electric generators (TEG) or vibration or electro-magnetic
power sources. Additionally, capacitors (e.g., supercapacitors) may
be used as an energy storage device and auxiliary power source for
the system. Device 200 may be configured to use low amounts of
power, operating only in conjunction with a harvested energy source
or with a battery. For example, the sampling period of any sensor
output monitoring may be optimized to save energy by drawing power
only during the sampling period, and the sensor may operate in a
"sleep mode" at all other times.
[0047] FIG. 3 is a diagram depicting an example of the device of
FIG. 1 attached to a vehicle brake assembly. The brake assembly may
include some or all of the components shown in FIG. 3. The system
includes transceiver 310, pressure plate 320, device 330, wear
indicator pin 340, brake carrier 350, signal 370, reflected signal
380, and attachment element 390. FIG. 3 is an example configuration
for a brake assembly and device 330, such that device 330 can
determine the length of wear indicator pin 340. Although labeled
separately, transceiver 310 may be a part of device 330.
[0048] The vehicle brake assembly includes pressure plate 320, wear
indicator pin 340, and brake carrier 350. Pressure plate 320 is
configured to move with respect to brake carrier 350 as the
vehicle's brakes wear down through use over time. Pressure plate
320 is an example of plate 180 shown in FIG. 1. Pressure plate 320
may be attached to a brake lining (e.g., a brake shoe a brake pad)
that presses against a rotating component of a wheel to reduce the
speed of the rotating component.
[0049] Because wear indicator pin 340 is physically coupled to
pressure plate 320, wear indicator pin 340 likewise moves with
respect to brake carrier 350, and with respect to device 330, which
is physically coupled to brake carrier 350 through attachment
element 390. In the example of FIG. 3, wear indicator pin 340 is
attached to pressure plate 320 and protrudes through brake carrier
350. Because wear indicator pin 340 moves with respect to brake
carrier 350, the exposed portion of wear indicator pin 340, or
remaining wear length 360, decreases with use of the brakes. As
remaining wear length 360 approaches zero, and the tip or surface
of wear pin 340 approaches the surface of brake carrier 350, the
brakes may be nearing the time at which they need to be replaced.
When the surface of wear pin 340 is flush with the surface of brake
carrier 350, the lifespan of the vehicle's brakes may be presumed
to be over, or may be considered dangerous to continue using, as
this may result in brake failure.
[0050] Device 330 is configured to accurately measure and monitor
remaining wear length 360 of wear indicator pin 340, by measuring
distance 362 between the tip of wear pin 340 and transceiver 310,
positioned opposite the tip of wear pin 340.
[0051] Transceiver 310 is configured to transmit emitted signal 370
at a first time toward the tip of wear pin 340. Emitted signal 370
then reflects off the tip of wear pin 340 and becomes reflected
signal 380. Transceiver 310 is configured to receive or detect
reflected signal 380 at a second time. In some examples, device 330
is then configured to determine distance 362 between transceiver
310 and the tip of wear pin 340, which is equivalent to the
distance travelled by emitted signal 370, which is also equivalent
to the distance travelled by reflected signal 380. This measurement
may be determined by the relation
d 1 = v ( t 2 - t 1 2 ) ( 1 ) ##EQU00001##
where: [0052] d.sub.1 is distance 362 between transceiver 310 and
the tip of wear pin 340; [0053] v is the known velocity of signals
370 and 380, for example, the speed of light, c; [0054] t.sub.2 is
the time at which reflected signal 380 was received by transceiver
310; and [0055] t.sub.1 is the time at which emitted signal 370 was
transmitted by transceiver 310. From here, remaining wear length
360 may be determined by the relation shown in Equation (2).
[0055] L=d.sub.2-d.sub.1 (2)
where: [0056] L is remaining wear length 360; [0057] d.sub.2 is the
known distance between transceiver 310 and brake carrier 350 (or
equivalently, the length of device 330); and [0058] d.sub.1 is the
previously determined distance 362 between transceiver 310 and the
tip of wear pin 340.
[0059] Over time, the tip of wear indicator pin 340 moves in the
positive y-axis direction towards the edge of brake carrier 350. As
wear indicator pin 340 moves, distance 362 increases, and remaining
wear length 360 decreases. Device 330 may be configured to store a
threshold length for wear indicator pin 340, where the threshold
length may indicate remaining wear length 360 when the brakes
should be replaced. As an alternative or additional technique,
device 330 may determine the remaining use of the brake assembly
directly from the time difference of signals 370 and 380.
Number of remaining braking events=L/(Wear per braking event)
(3)
Wear per braking event=L.sub.original/(Original number of braking
events) (4)
[0060] Using Equation (3), the processing circuitry of device 330
may be configured to then determine an estimate of the number of
remaining braking events (e.g., landings) that can occur with
optimal braking before replacing the brake lining. The processing
circuitry can determine the number of remaining braking events by
dividing the remaining wear length 360 (L) by the wear per braking
event (e.g., rate of wear). The processing circuitry can determine
the wear per braking event by dividing the original length
(L.sub.original) of wear indicator pin 340 by the original number
of braking events specified by the part supplier, using Equation
(4).
[0061] For example, if the original length of wear indicator pin
340 is one inch (e.g., approximately twenty-five millimeters), and
the part supplier states that the new brake lining can perform for
one thousand braking events, the processing circuitry determines
that the wear per braking event is 0.001 inches or 0.025
millimeters. If the processing circuitry of device 330 later
determines that a new length of wear indicator pin 340 is ten
millimeters less than the original, the processing circuitry may
determine that the new length is fifteen millimeters. Using a rate
of wear of 0.025 millimeters per braking event and Equation (3),
the processing circuitry determines that the remaining use of the
brake lining is six hundred braking events.
[0062] FIGS. 4A and 4B are perspective views of examples of a
device 430 and a wear pin. Device 430 is an example of device 100
shown in FIG. 1. Device 430 is positioned such that transceiver 410
is placed opposite the tip or end surface of wear indicator pin
460. Although labeled separately, transceiver 410 may be a part of
device 430. FIGS. 4A and 4B depict wear indicator pin 460 as a
cylinder, but wear indicator pin 460 may have a rectangular shape,
a conical shape, and/or any other suitable shape.
[0063] FIG. 5 is a conceptual block diagram illustrating a system
with data analytics 566 and cloud applications 564. The computing
system(s) of avionics bay 560 and handheld device 570 are examples
of external devices to which processing circuitry 540 can
communicate data and alerts. Avionics bay 560 can host embedded
systems that are connected to the rest of the vehicle that contains
brake assembly 550. Transceiver 510 reflects a signal off of a wear
pin indicator within brake assembly 550. Processing circuitry 540
determines timestamps indicative of the transmitted and reflected
signals. Processing circuitry 540 is configured to use the
timestamps to determine a remaining wear length of the wear
indicator pin. The determined estimate of remaining use, the
determined wear pin length measurement, and the time information
may then be transferred to various other systems and interfaces for
further use.
[0064] For example, the wear pin length and a corresponding
predicted remaining brake lifespan, or an estimated remaining
number of braking events, may be transmitted for display in
avionics bay of an aircraft on which the brake assembly on which
the measurement was made. A log of wear pin measurements may be
stored to analyze braking and wear trends over time. This data may
be kept in storage 562 or transferred offsite to cloud storage 564
for wider access by the airline. The wear pin measurement data can
be used by airlines or the operators of other vehicles for further
analytics 566, monitoring the rate and trend at which brake wear is
happening per landing. Based on the trend data airline can predict
how many more takeoffs or landings can be performed before brake
maintenance or brake replacements are required.
[0065] Another example application of enhanced data analytics 566
is to design a customized training plan for pilots for cases where
considerable amount of brake pin wear is observed frequently during
landings and are attributed to judgment error of vehicle operators,
for example, landing the aircraft long and applying hard brakes to
stop the aircraft under normal weather conditions. Data analytics
566 may associate each braking event with data such as vehicle
operator, weather conditions, runway length, runway surface type
(asphalt, concrete, etc.), runway conditions, and/or other relevant
data. Data analytics 566 may determine which vehicle operators are
"hard brakers" based on the rate of wear associated with each
vehicle operator and each braking event.
[0066] Another example application of enhanced data analytics 566
is to design and implement an improved pricing mechanism. The wear
pin measurement trend data, combined with operating conditions
data, for example, runway data, contamination data, weather, and
climate conditions, may be used by brake suppliers to design a
better pricing mechanism. For example, if the brake system is used
in harsh or severe weather or runway conditions, the tendency of
hard braking would be higher, and the brakes would wear down
faster. Knowing such details, a brake supplier could implement a
pricing system based on an estimated cost per braking event. The
pricing system can be tailored to the individual needs and
environments of each customer. For example, an original equipment
manufacturer (OEM) may determine pricing and the terms of annual
maintenance contracts based on data determined by processing
circuitry 540.
[0067] Another application of the wear pin measurement data is for
use by a maintenance technician or group 580. Determined brake data
may be sent to handheld device 570, for example a device dedicated
solely to brake assembly data, or alternatively, a multi-purpose
device such as a smartphone. Maintenance operations 580 may use the
information to monitor when the brake assembly is due for
maintenance or replacement, and prepare the replacement parts,
thereby reducing the turnaround time and aircraft downtime.
[0068] In some examples, a computing device (e.g., processing
circuitry 540, the computing system(s) of avionics bay 560, or
handheld device 570) and/or an application (e.g., cloud application
564 or data analytics 566) may be configured to determine multiple
lengths of the wear pin over time. For example, processing
circuitry 540 may be configured to cause transceiver 510 to
transmit and receive signals at a first time and a second time,
where processing circuitry 540 determines a first length of the
wear pin based on the first time and the second time. Processing
circuitry 540 may be further configured to cause transceiver 510 to
transmit and receive signals at a third time and a fourth time,
where processing circuitry 540 determines a second length of the
wear pin based on the third time and the fourth time. Processing
circuitry 540 may perform additional measurements of the length of
the wear pin.
[0069] Based on the multiple measurements of the length, the
computing device and/or the application may determine a number of
braking events between measurements based on records of the vehicle
operation. The computing device and/or the application may
determine a rate of wear based on the lengths and the number of
braking events. The rate of wear may indicate whether the vehicle
operator is a hard braker. The presence or absence of other factors
such as weather, surface type, and/or surface conditions can also
affect the rate of wear. The computing device and/or the
application may store the lengths and the rate of wear to storage
562. If the computing device and/or the application determines that
the rate of wear exceeds a threshold rate, the computing device
and/or the application can generate an alert.
[0070] The computing device and/or the application may determine an
estimated remaining use on brake assembly 550 based on the
length(s) and/or the rate of wear. Other factors that affect the
estimated remaining use include the expected type of operation in
the future, the expected weather conditions in the future (e.g.,
based on location and time of year), and expected surface types in
the future. The computing device and/or the application may
determine the remaining use in terms of time (e.g., a number of
days or weeks) or in terms of the number of remaining braking
events (e.g., ten remaining landings before replacement).
[0071] FIG. 6 shows a flowchart for an example technique for
determining an estimated remaining use of a brake assembly, in
accordance with some examples of this disclosure. The technique of
FIG. 6 is described with reference to device 100 of FIG. 1,
although devices 200, 330, and 430 may also perform similar
techniques. In the example of FIG. 6, processing circuitry 120
causes transceiver 110 to transmit signal 140 at a first time, for
example a laser or other electromagnetic signal, toward an exposed
end of wear indicator pin 160 (602). In the example of FIG. 6,
transceiver 110 receives, for example by a receiving component of
transceiver 110 such as an antenna, reflection 150 of transmitted
signal 140 at a second, later time (604). Transceiver 110 may have
a "transmit" antenna that is separate from the "receive" antenna,
or transceiver 110 may include one or more antennas configured to
both transmit signal 140 and receive signal 150.
[0072] In the example of FIG. 6, processing circuitry 120
determines a time difference between the first time of transmission
and the second time of receipt (606). Based on the time difference,
processing circuitry 120 may then determine a distance travelled by
signals 140 and 150 based on the speed of signals 140 and 150 and
the difference between the first time and the second time.
Processing circuitry 120 may use the first recorded time, the
second recorded time, and the known speed of the signal to
determine the distance travelled by the signal between the first
time and the second time. These values may be related by the basic
equation that the velocity of the signal is equivalent to the
distance travelled by the signal divided by the time during which
the signal travels that distance, as shown in Equation (1) above.
The distance travelled by the signal is the velocity of the signal
multiplied by the time during which the signal travels.
[0073] In the example of FIG. 6, processing circuitry 120
determines an estimated remaining use of brake assembly 170 based
on the time difference between the first time and the second time
(608). Processing circuitry 120 can determine the estimated
remaining use of brake assembly 170 directly from the time
difference, or processing circuitry 120 may first determine the
length of wear indicator pin 160 based on the difference of the
first time and the second time. The length of wear indicator pin
160 may be an exposed length of wear indicator pin 160. Processing
circuitry 120 may determine the length of wear indicator pin 160 as
the difference between the known length between the distal end of
the wear indicator pin 160 and the source of transmitted signal
140, and the previously determined distance travelled by reflected
signal 150. The "distal" end of wear indicator pin 160 refers to
the end in contact with the brakes (e.g., plate 180 shown in FIG. 1
and/or pressure plate 320 shown in FIG. 3), where the "proximal"
end is closer to transceiver 110.
[0074] The techniques of this disclosure may be implemented in a
device or article of manufacture including a computer-readable
storage medium. The term "processing circuitry," as used herein may
refer to any of the foregoing structure or any other structure
suitable for processing program code and/or data or otherwise
implementing the techniques described herein. Elements of
processing circuitry 120 and 220 may be implemented in any of a
variety of types of solid state circuit elements, such as CPUs, CPU
cores, GPUs, digital signal processors (DSPs), application-specific
integrated circuits (ASICs), a mixed-signal integrated circuits,
field programmable gate arrays (FPGAs), microcontrollers,
programmable logic controllers (PLCs), programmable logic device
(PLDs), complex PLDs (CPLDs), a system on a chip (SoC), any
subsection of any of the above, an interconnected or distributed
combination of any of the above, or any other integrated or
discrete logic circuitry, or any other type of component or one or
more components capable of being configured in accordance with any
of the examples disclosed herein.
[0075] Devices 100 and 200 may include one or more memory devices,
such as memory devices 130 and 230, that include any volatile or
non-volatile media, such as a RAM, ROM, non-volatile RAM (NVRAM),
electrically erasable programmable ROM (EEPROM), flash memory, and
the like. Memory devices 130 and 230 may store computer-readable
instructions that, when executed by processing circuitry, cause the
processing circuitry to implement the techniques attributed herein
to processing circuitry 120 and 220.
[0076] Elements of processing circuitry 120 and 220 and/or memory
device 130 and 230 may be programmed with various forms of
software. The processing circuitry and/or the transceiver may be
implemented at least in part as, or include, one or more executable
applications, application modules, libraries, classes, methods,
objects, routines, subroutines, firmware, and/or embedded code, for
example. Elements of processing circuitry 120 and 220 and/or memory
device 130 and 230 as in any of the examples herein may be
implemented as a device, a system, an apparatus, and may embody or
implement a method of determining an estimated altitude of a
melting layer.
[0077] The techniques of this disclosure may be implemented in a
wide variety of computing devices. Any components, modules or units
have been described to emphasize functional aspects and does not
necessarily require realization by different hardware units. The
techniques described herein may be implemented in hardware,
software, firmware, or any combination thereof. Any features
described as modules, units or components may be implemented
together in an integrated logic device or separately as discrete
but interoperable logic devices. In some cases, various features
may be implemented as an integrated circuit device, such as an
integrated circuit chip or chipset.
[0078] Various examples of the disclosure have been described. Any
combination of the described systems, operations, or functions is
contemplated. These and other examples are within the scope of the
following claims.
* * * * *