U.S. patent application number 14/714193 was filed with the patent office on 2016-11-17 for ice breaking strategy for vehicle side windows.
The applicant listed for this patent is Ford Global Technologies, LLC. Invention is credited to Aed M. Dudar, Mahmoud Yousef Ghannam.
Application Number | 20160333627 14/714193 |
Document ID | / |
Family ID | 57208497 |
Filed Date | 2016-11-17 |
United States Patent
Application |
20160333627 |
Kind Code |
A1 |
Dudar; Aed M. ; et
al. |
November 17, 2016 |
ICE BREAKING STRATEGY FOR VEHICLE SIDE WINDOWS
Abstract
Described herein is a vehicle side window system and method for
implementing an ice breaking strategy. The ice breaking strategy
receives and analyzes sensor information from one or more
environmental sensors to determine when to preemptively implement
an ice breaking routine. The ice breaking strategy is also capable
of monitoring one or more components of the vehicle side window
system to determine when to cease the ice breaking routine.
Inventors: |
Dudar; Aed M.; (Canton,
MI) ; Ghannam; Mahmoud Yousef; (Canton, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ford Global Technologies, LLC |
Dearborn |
MI |
US |
|
|
Family ID: |
57208497 |
Appl. No.: |
14/714193 |
Filed: |
May 15, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02P 25/06 20130101;
H02H 7/0851 20130101; H02K 7/14 20130101; H02P 31/00 20130101; E05F
15/71 20150115; E05F 15/695 20150115; E05Y 2900/55 20130101 |
International
Class: |
E05F 15/71 20060101
E05F015/71; H02P 7/00 20060101 H02P007/00; E05F 15/695 20060101
E05F015/695 |
Claims
1. A vehicle comprising: a sensor configured to sense an
environmental condition; a motor configured to move a window; and a
control unit configured to: operate in an off state before
receiving a wake up signal; receive the wake up signal enabling the
control unit to receive sensor information from the sensor; receive
the sensor information, the sensor information identifying an
environmental condition sensed by the sensor; analyze the sensor
information by comparing the environmental condition to an
environmental condition limit; determine the ice breaking condition
is satisfied when the environmental condition satisfies the
environmental condition limit; and control the motor to rotate
according to an ice breaking routine when the ice breaking
condition is satisfied.
2. The vehicle of claim 1, wherein the sensor includes one or more
of a temperature sensor configured to sense an ambient air
temperature, a humidity sensor configured to sense a humidity
level, and a precipitation sensor configured to sense a
precipitation level.
3. The vehicle of claim 1, wherein the wake up signal is received
from a vehicle key FOB.
4. The vehicle of claim 1, wherein the wake up signal is received
to correspond to a predetermined time of day or a predetermined
time interval.
5. (canceled)
6. (canceled)
7. The vehicle of claim 1, wherein the environmental condition is a
temperature reading, and the environmental condition limit is a
predetermined temperature; and wherein the control unit is
configured to determine the ice breaking condition is satisfied
when the temperature reading is less than the predetermined
temperature.
8. The vehicle of claim 1, wherein the environmental condition is a
humidity reading, and the environmental condition limit is a
predetermined humidity; and wherein the control unit is configured
to determine the ice breaking condition is satisfied when the
humidity reading is less than the predetermined humidity.
9. The vehicle of claim 1, wherein the environmental condition is a
precipitation reading, and the environmental condition limit is a
predetermined precipitation; and wherein the control unit is
configured to determine the ice breaking condition is satisfied
when the temperature reading is greater than the predetermined
precipitation.
10. The vehicle of claim 1, wherein the environmental condition is
at least one of a temperature reading, a humidity reading, and a
precipitation reading, and the environmental condition limit is at
least one of a predetermined temperature, a predetermined humidity,
and a predetermined precipitation; and wherein the control unit is
configured to determine the ice breaking condition is satisfied
when the at least one of the temperature reading, the humidity
reading, and the precipitation reading satisfies the at least one
of the predetermined temperature, the predetermined humidity, and
the predetermined precipitation.
11. The vehicle of claim 1, wherein the control unit is further
configured to: monitor a motor current of the motor; determine the
motor current reaches a stall current during the ice breaking
routine; and control the ice breaking routine to stop when the
motor current is determined not to reach the stall current.
12. The vehicle of claim 1, wherein the control unit is further
configured to: monitor at least one of a motor voltage, a motor
torque, and a motor speed; determine the motor reaches at least one
of a stall voltage, a stall torque, and a stall speed during the
ice breaking routine; and control the ice breaking routine to stop
when the motor is determined not to reach at least one of the stall
voltage, the stall torque, and the stall speed.
13. A vehicle comprising: a sensor configured to sense an
environmental condition; a motor configured to move a window; and a
control unit configured to: receive sensor information identifying
the environmental condition from the sensor while the control unit
is in an off state; comparing the environmental condition to an
environmental condition limit; determine an ice breaking condition
is satisfied when the comparison is satisfied; and control an ice
breaking routine based on the determination.
14. The vehicle of claim 13, wherein the control unit is configured
to control the motor to rotate according to an ice breaking routine
when the ice breaking condition is determined to be satisfied.
15. (canceled)
16. The vehicle of claim 13, wherein the environmental condition is
a temperature reading, and the environmental condition limit is a
predetermined temperature; and wherein the control unit is
configured to determine the ice breaking condition is satisfied
when the temperature reading is less than the predetermined
temperature.
17. The vehicle of claim 13, wherein the environmental condition is
a humidity reading, and the environmental condition limit is a
predetermined humidity; and wherein the control unit is configured
to determine the ice breaking condition is satisfied when the
humidity reading is less than the predetermined humidity.
18. The vehicle of claim 1, wherein the environmental condition is
a precipitation reading, and the environmental condition limit is a
predetermined precipitation; and wherein the control unit is
configured to determine the ice breaking condition is satisfied
when the temperature reading is greater than the predetermined
precipitation.
19. The vehicle of claim 13, wherein the environmental condition is
at least one of a temperature reading, a humidity reading, and a
precipitation reading, and the environmental condition limit is at
least one of a predetermined temperature, a predetermined humidity,
and a predetermined precipitation; and wherein the control unit is
configured to determine the ice breaking condition is satisfied
when the at least one of the temperature reading, the humidity
reading, and the precipitation reading satisfies the at least one
of the predetermined temperature, the predetermined humidity, and
the predetermined precipitation.
20. The vehicle of claim 13, wherein the control unit is further
configured to: monitor at least one of a motor current, a motor
voltage, a motor torque, and a motor speed; determine the motor
reaches at least one of a stall current, stall voltage, a stall
torque, and a stall speed during the ice breaking routine; and
control the ice breaking routine to stop when the motor is
determined not to reach at least one of the stall current, the
stall voltage, the stall torque, and the stall speed.
Description
BACKGROUND
[0001] This disclosure generally relates to a vehicle including
components for implementing an ice breaking strategy for vehicle
side windows.
[0002] Under certain conditions, ice has been found to form on
vehicle side windows. Requiring a driver or passenger to leave the
comforts of the vehicle to scrape off the ice formed on the outside
of the vehicle side window is a nuisance for the driver or
passenger as the outside conditions are likely to be cold and
uncomfortable. Further, solutions for breaking up the ice from the
inside by operating the vehicle side windows manually may not be
sufficient to break up substantial ice buildup.
SUMMARY
[0003] This application is defined by the appended claims. The
description summarizes aspects of embodiments of the disclosure and
should not be used to limit the claims. Other implementations are
contemplated in accordance with the techniques described herein, as
will be apparent upon examination of the following drawings and
description, and such implementations are intended to be within the
scope of this disclosure.
[0004] Exemplary embodiments provide a vehicle including components
configured to implement an ice breaking strategy for vehicle side
windows. The ice breaking strategy obtains sensor information from
one or more environmental sensors of the vehicle, and determines
when to initiate a preemptive ice breaking routine based on the
obtained sensor information. The sensor information may be obtained
while the vehicle engine is not on, while vehicle electrical
components are not in an on state due to an ignition setting, or at
some other time when a passenger is not seated within the vehicle.
For example, the sensor information may be analyzed to determine
whether an ice forming condition exists outside of the vehicle. By
monitoring the sensor information for environmental conditions that
may allow for ice to form on the vehicle side windows, the ice
breaking strategy may then implement an ice breaking routine before
ice is allowed to form on the vehicle side windows. Implementing
the preemptive ice breaking routine is advantageous to prevent
significant ice formation on the vehicle side window, where a power
window motor may not be able to move a door window to break off
significant ice formation.
[0005] According to some embodiments, a vehicle comprising a sensor
configured to sense an environmental condition, a motor configured
to move a window, and a control unit is disclosed. The control unit
may be configured to operate in an off state before receiving a
wake up signal, receive the wake up signal enabling the control
unit to receive sensor information from the sensor, and control an
ice breaking routine based on the sensor information.
[0006] According to some embodiments, a vehicle comprising a sensor
configured to sense an environmental condition, a motor configured
to move a window, and a control unit is disclosed. The control unit
may be configured to receive sensor information from the sensor
while the control unit is in an off state, analyze the sensor
information, determine whether an ice breaking condition is
satisfied based on the analysis, and control an ice breaking
routine based on the determination.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] For a better understanding, reference may be made to
embodiments shown in the following drawings. The components in the
drawings are not necessarily to scale and related elements may be
omitted so as to emphasize and clearly illustrate the novel
features described herein. In addition, system components can be
variously arranged, as known in the art. In the figures, like
referenced numerals may refer to like parts throughout the
different figures unless otherwise specified.
[0008] FIG. 1 illustrates an exemplary vehicle side window
system;
[0009] FIG. 2 illustrates a flow chart describing a process for
implementing an ice breaking strategy, according to some
embodiments;
[0010] FIG. 3 illustrates a flow chart describing a process for
implementing an ice breaking strategy, according to some
embodiments;
[0011] FIG. 4 illustrates a combined current and voltage graph
plotting exemplary current and voltage values during the
implementation of the ice breaking strategy, according to some
embodiments;
[0012] FIG. 5 illustrates a graph plotting exemplary torque and
speed values for a window motor, according to some embodiments;
and
[0013] FIG. 6 illustrates a block diagram for an exemplary wake up
circuit torque of the vehicle side window system, according to some
embodiments.
DETAILED DESCRIPTION
[0014] While the invention may be embodied in various forms, there
are shown in the drawings, and will hereinafter be described, some
exemplary and non-limiting embodiments, with the understanding that
the present disclosure is to be considered an exemplification and
is not intended to limit the features described herein to the
specific embodiments illustrated. Not all of the components
described in this disclosure may be required, however, and some
implementations may include additional, different, or fewer
components from those expressly described in this disclosure.
Variations in the arrangement and type of the components may be
made without departing from the spirit or scope of the claims as
set forth herein.
[0015] Under certain environmental conditions, vehicle side windows
may freeze or form ice over portions of the vehicle side windows.
When this occurs, the vehicle side windows may become stuck and
unable to move up or down. For example, the vehicle side window may
be prevented from moving from a closed position to an open
position, or moving from an open position to a closed position,
when the vehicle side window is frozen or has ice formed over
portions of the vehicle side window.
[0016] In power window applications, a passenger may try to break
up ice formed on the vehicle side window by attempting to actuate
the vehicle side window up and/or down. However, when the ice
formed on the vehicle side window is significant, a torque force
available from a power window motor may not be sufficient to break
the ice built up on the vehicle side window.
[0017] It follows that the current disclosure describes a vehicle
side window system and method for implementing an ice breaking
strategy that preemptively prevents ice formation on the vehicle
side windows. The ice breaking strategy involves receiving sensor
information from one or more environmental sensors that are
included as part of a vehicle system. The different types of
environmental sensors and sensor information that may be utilized
by the vehicle side window system are described in more detail
herein. The sensor information may then be analyzed to determine
whether an ice breaking condition is satisfied. If the ice breaking
condition is determined to be satisfied based on the sensor
information, an ice breaking routine is implemented. The ice
breaking routine is described in more detail herein. If the ice
breaking condition is not satisfied, the vehicle side window system
may revert to receiving sensor information. After, or in some
embodiments during, implementing the ice breaking routine, the
vehicle side window system may monitor for an ice broken condition.
The ice broken condition is described in more detail herein. If the
ice broken condition is determined to be satisfied, the ice
breaking routine is ceased. If the ice broken condition is
determined not to be satisfied, the ice breaking routine may be
continued, or started up again.
[0018] FIG. 1 illustrates a vehicle side window system 100
according to some embodiments. The vehicle side window system
includes a control unit 101 in communication with environmental
sensors 110, where control unit 101 may communicate with
environmental sensors 110 via either wired or wireless
communication protocols. Environmental sensors 110 may include one
or more of a temperature sensor 111 (e.g., ambient air temperature
sensor), a humidity sensor 112, and a precipitation sensor 113.
Control unit 101 may be, for example, a body control module (BCM),
a power-train control module (PCM), or another computing device
comprised of a processor and a vehicle memory configured to control
one or more components of the vehicle side window system 100.
Control unit 101 may also be configured to send and/or receive
information from one or more components of the vehicle side window
system 100. Although control unit 101 is depicted as receiving
sensor information from environmental sensors 110 directly,
according to some embodiments control unit 101 may receive the
sensor information from another computing device (not specifically
illustrated), where the other computing device receives the sensor
information from the environmental sensors 110 directly via either
a wired or wireless connection protocol.
[0019] Vehicle side window system 100 also includes automatic
lock/unlock switch 121, door handle 122, power door actuator 123,
latch 124, and speaker 150. A passenger's control of automatic
lock/unlock switch 121 will control power door actuator 123 to
engage or disengage latch 124 for locking and unlocking door 120.
Vehicle side window system 100 also includes a window assembly
including first window channel 131, second window channel 132,
power window switch 140, window motor 141 (e.g., a DC motor),
window regulator 142, and window 143. A passenger's control of
power window switch 140 will control window motor 141 to rotate in
a window-down direction or window-up direction. When window motor
141 is controlled to rotate in the window-down direction, window
regulator 142 is also rotated in a window-down direction to bring
window 143 down and towards a window-down position. When window
motor 141 is controlled to rotate in the window-up direction,
window regulator 142 is also rotated in a widow-up direction to
bring window 143 up towards a window-up position. As window 143
travels up and down, first window channel 131 and second window
channel 132 help guide window 143 along a set path. In addition to
controlling movement of window 143 based on the passenger's input
to power window switch 140, movement of window 143 may be
controlled by control unit 101 according to the ice breaking
strategy described herein.
[0020] FIG. 2 illustrates flow chart 200 describing an ice breaking
strategy process. The ice breaking strategy process determines when
to implement an ice breaking routine, and also determines when to
cease the ice breaking routine.
[0021] At 201, a determination is made whether a wake up condition
is satisfied. This determination at 201 may be included in the ice
breaking strategy process when the vehicle system, including the
control unit 101, is otherwise in an off, or less than fully
functional, state. The off state may correspond to a state where
the vehicle ignition has not been engaged to turn on the vehicle
engine or has not been engaged to turn on one or more electrical
systems of the vehicle. While the vehicle is in such an off state,
control unit 101 may receive a wake up signal. The wake up signal
may be received by control unit 101 when one or more buttons (e.g.,
unlock button, lock button, truck open button, emergency alert
button) on a vehicle key FOB associated to the vehicle is pressed
and a corresponding FOB signal is received by the vehicle. The FOB
signal may be routed to be received by control unit 101 at, for
example, a dedicated wake pin of control unit 101. Receiving the
FOB signal by control unit 101 will result in the wake up condition
of 201 being satisfied.
[0022] In addition or alternatively, an ice breaking routine time
may be previously set such that the wake up condition of 201 is
satisfied when the ice breaking routine time is satisfied. For
example, if the ice breaking routine time is set to be a specific
time of day (e.g., 2:00 a.m.), the wake up condition of 201 may be
satisfied when control unit 101 determines a current time is equal
to the specific time of day identified in the ice breaking routine
time. In another example, if the ice breaking routine time is a
specific time interval (e.g., 6 hour interval), the wake up
condition of 201 may be satisfied when control unit 101 determines
a length of time since the ice breaking routine has last been
implemented equals the specific time interval identified in the ice
breaking routine time.
[0023] If the wake up condition is determined not to be satisfied
at 201, the ice breaking strategy process reverts back to a
starting point. If the wake up condition is determined to be
satisfied at 201, at 202, control unit 101 receives sensor
information from one or more environmental sensors 110. For
example, control unit 101 may receive ambient air temperature
readings sensed by temperature sensor 111, humidity readings sensed
by humidity sensor 112, and precipitation readings sensed by
precipitation sensor 113.
[0024] At 203, the received sensor information is analyzed by
control unit 101. For example, control unit 101 may compare the
ambient air temperature reading sensed by temperature sensor 111
against a predetermined ice forming temperature value. Control unit
101 may also compare the humidity reading sensed by humidity sensor
112 against a predetermined ice forming humidity value. Control
unit 101 may also compare precipitation reading sensed by
precipitation sensor 113 against a predetermined ice forming
precipitation value. In addition or alternatively, control unit 101
may analyze one or more of the ambient air temperature reading,
humidity reading, and/or precipitation reading to compare the
analyzed readings information from environmental sensors 110 to a
predetermined ice forming condition. The predetermined ice forming
temperature value, predetermined ice forming humidity value,
predetermined ice forming precipitation value, and predetermined
ice forming condition information may be stored on a vehicle memory
accessible by control unit 101.
[0025] At 204, control unit 101 may determine whether an ice
breaking condition is satisfied. For example, the ice breaking
condition may be satisfied when the ambient air temperature reading
is determined to be lower than the predetermined ice forming
temperature value. In addition or alternatively, the ice breaking
condition may be satisfied when the humidity reading is above, or
below, the predetermined ice forming humidity value. In addition or
alternatively, the ice breaking condition may be satisfied when the
precipitation reading is above the predetermined ice forming
precipitation value. In addition or alternatively, the ice breaking
condition may be satisfied when the analyzed readings information
from environmental sensors 110 is determined to satisfy the
predetermined ice forming condition.
[0026] If the ice breaking condition is not satisfied at 204, the
ice breaking strategy process may revert back to a starting point.
If the ice breaking condition is satisfied at 204, control unit 101
may implement the ice breaking routine at 205. The ice breaking
routine may include pulsing window motor 141 between the
window-down direction and window-up direction at a high torque to
move window 143 in a rapid motion. The rotational speed of window
motor 141 during the ice breaking routine may be faster, or slower,
than the rotational speed of window motor 141 during a normal
passenger operational mode, as described herein. By rotating window
motor 141 at the high torque during the ice breaking routine, ice
may be prevented from forming on window 143. By rotating window
motor 141 at the high torque during the ice breaking routine, thin
amounts of ice may be proactively broken off window 143. The ice
breaking routine at 205 may be implemented for a set number of
window motor 141 pulse cycles, a predetermined time period, or
until an ice broken condition is satisfied at 207.
[0027] At 206, control unit 101 monitors for an ice broken
condition. The monitoring at 206 may be implemented while the ice
breaking routine is running, or after the ice breaking routine has,
at least temporarily, ceased. The monitoring at 206 may include
control unit 101 monitoring a motor current or motor voltage of
window motor 141. For example, FIG. 4 illustrates a first graph 401
plotting motor current against time, and a second graph 402
plotting motor voltage against time, where the time for the first
graph 401 and the second graph 402 are the same. From time t.sub.1
to t.sub.2 control unit 101 controls window motor 141 to attempt to
rotate in the window-down direction as depicted by the negative
voltage from t.sub.1 to t.sub.2. However, based on the motor
current hitting the stall current between t.sub.1 to t.sub.2,
control unit 101 is able to determine that window motor 141 may be
stuck. From t.sub.2 to t.sub.3, control unit 101 controls window
motor 141 to attempt to rotate in the window-up direction as
depicted by the positive voltage from t.sub.2 to t.sub.3. However,
based on the motor current hitting the stall current between
t.sub.2 to t.sub.3, control unit 101 is able to determine that
window motor 141 may still be stuck. The control unit 101 may pulse
the window motor 141 until time t.sub.4 where the motor current is
detected not to reach the stall current as in previous pulsating
periods. Each pulsating period may last for a same length of time.
Detecting the stall current is not reach as in previous pulsating
periods following time t.sub.4 may correspond to control unit 101
determining that the ice broken condition has been satisfied at
207. Alternatively, control unit 101 may detect motor voltage
lasting at the negative voltage following time t.sub.4 and
determine that the ice broken condition has been satisfied at
207.
[0028] In addition or alternatively, control unit 101 may reference
a speed vs. torque curve as illustrated by third graph 500. Control
unit 101 may monitor a torque of window motor 141 to determine
window motor 141 is in a stuck state when a high torque and low
speed is detected, as illustrated by point P1. Control unit 101 may
monitor the torque of window motor 141 to determine window motor
141 is in a non-stuck (i.e., no load) state when a low torque and
high speed is detected, as illustrated by point P3. Control unit
101 may monitor the torque of window motor 141 to determine window
motor 141 is in an operational state when a torque between point P1
and P3 is detected along with a speed between P1 and P3 is
detected. Detecting the window motor 141 is in an operational state
enables control unit 101 to determine the ice broken condition has
been satisfied at 207.
[0029] If control unit 101 does not determine the ice broken
condition has been satisfied at 207, the ice breaking strategy
process may revert to implementing the ice breaking routine at
205.
[0030] FIG. 3 illustrates flow chart 300 describing an ice breaking
strategy process where one or more of environmental sensors 110
(e.g., temperature sensor 111, humidity sensor 112, or
precipitation sensor 113) are coupled to a Hot At All Times (HAAT)
circuit that allows one or more environmental sensors 110 to be
active and sensing environmental conditions even while the vehicle
is in the off state. The ice breaking strategy process determines
when to implement an ice breaking routine, and also determines when
to cease the ice breaking routine.
[0031] According to such embodiments, at 301 one or more
environmental sensors 110 may be active to receive sensor
information, as described herein with respect to flow chart 200.
For example, control unit 101 may receive ambient air temperature
readings sensed by temperature sensor 111, humidity readings sensed
by humidity sensor 112, and precipitation readings sensed by
precipitation sensor 113.
[0032] At 302, sensor information received from the one or more
active environmental sensors 110 may be analyzed. For example,
control unit 101 may compare an ambient air temperature reading
sensed by temperature sensor 111 against a predetermined wake up
condition temperature value. Control unit 101 may also compare a
humidity reading sensed by humidity sensor 112 against a
predetermined wake up condition humidity value. Control unit 101
may also compare a precipitation reading sensed by precipitation
sensor 113 against a predetermined wake up condition precipitation
value. In addition or alternatively, control unit 101 may analyze
one or more of the ambient air temperature reading, humidity
reading, and/or precipitation reading to compare the analyzed
sensor readings information from environmental sensors 110 to a
predetermined wake up condition. The predetermined wake up
condition temperature value, predetermined wake up condition
humidity value, predetermined wake up condition precipitation
value, and predetermined wake up condition information may be
stored on a vehicle memory accessible by control unit 101.
[0033] At 303, control unit 101 may determine whether the wake up
condition is satisfied. For example, the wake up condition may be
satisfied when the ambient air temperature reading is determined to
be lower than the predetermined wake up condition temperature
value. In addition or alternatively, the wake up condition may be
satisfied when the humidity reading is above, or below, the
predetermined wake up condition humidity value. In addition or
alternatively, the wake up condition may be satisfied when the
precipitation reading is above the predetermined wake up condition
precipitation value. In addition or alternatively, the wake up
condition may be satisfied when the analyzed sensor readings
information from environmental sensors 110 is determined to satisfy
the predetermined wake up condition. In addition or alternatively,
the wake up condition may be satisfied when a FOB signal is
received at control unit 101 in addition to any one or more of the
other wake up condition satisfying conditions described herein.
[0034] If the wake up condition is not satisfied at 303, the ice
breaking strategy process may revert back to a starting point. If
the ice breaking condition is satisfied at 303, control unit 101
may implement the ice breaking routine at 304. The ice breaking
routine at 304 may be the same as the ice breaking routine
implemented with reference to flow chart 200.
[0035] At 305, control unit 101 monitors for an ice broken
condition. The monitoring for the ice broken condition at 305 may
be the same as the monitoring for the ice broken condition
implemented with reference to flow chart 200.
[0036] At 306, control unit 101 determines whether the ice broken
condition is satisfied. The determination of whether the ice broken
condition is satisfied at 306 may be the same as the determination
of whether the ice broken condition is satisfied implemented with
reference to flow chart 200.
[0037] If control unit 101 does not determine the ice broken
condition has been satisfied at 306, the ice breaking strategy
process may revert to implementing the ice breaking routine at
304.
[0038] FIG. 6 illustrates an exemplary wake up circuit 600
configured to detect a wake up condition for waking up control unit
101. The wake up circuit 600 is comprised of a first operational
amplifier (Op Amp) 610, a second Op Amp 620, an OR logical circuit
630, and control unit 101. A first input 601 to the first Op Amp
610 is coupled to temperature sensor 111, and supplies temperature
sensor readings sensed by temperature sensor 111 to a non-inverting
input of the first Op Amp 610. A second input 602 to the first Op
Amp 610 supplies a +5V voltage source to an inverting input of the
first Op Amp 610, where the +5V voltage source is coupled to a
first resistor R1 and the second resistor R2. The first resistor R1
and the second resistor R2 are chosen to correspond to a voltage of
temperature sensor 111 that is equal or less than 32 degrees
Fahrenheit. The voltage output for the first Op Amp 610 is
Vout=[(Voltage from temperature sensor 111)-5*(R2/R1+R2)].
[0039] A third input 603 to the second Op Amp 620 is coupled to
humidity sensor 112 in some embodiments and to precipitation sensor
113 in other embodiments. The third input 603 supplies humidity
sensor readings sensed by humidity sensor 112, or precipitation
sensor readings sensed by precipitation sensor 113, to a
non-inverting input of the second Op Amp 620.
[0040] A fourth input 604 supplies a +5V voltage source to an
inverting input of the second Op Amp 620, where the +5V voltage
source is coupled to a third resistor R3 and the fourth resistor
R4. The third resistor R3 and the fourth resistor R4 are chosen to
correspond to a voltage of humidity sensor 112 or a voltage of
precipitation sensor 113 equal to a precipitation (e.g., rain or
snow) amount greater than xx. The variable xx may, for example,
represent a rain sensor signal 10% above a dry output, such that if
dry weather output is equal to 0.0-5V, then the threshold may be
0.5V. The voltage output for the second Op Amp 620 is
Vout=[5*(R4/R3+R4)-(Voltage from humidity sensor 112)] or
Vout=[5*(R4/R3+R4)-(Voltage from precipitation sensor 113)].
[0041] When the ambient air temperature sensed by temperature
sensor 111 is equal to, or less than, 32 degrees Fahrenheit, the
first Op Amp 610 outputs 0 volts. Similarly, when the humidity
sensor 112 or precipitation sensor 113 senses less than xx (e.g.,
10%) amount of precipitation, the second Op Amp 620 outputs 0
volts. When both the first Op Amp 610 and the second Op Amp 620
output 0 volts, a voltage to the wake up pin 105 is also 0 volts
which causes control unit 101 to wake up and begin the processes as
described herein with reference to flow chart 200 and flow chart
300.
[0042] Any process descriptions or blocks in the figures, should be
understood as representing modules, segments, or portions of code
which include one or more executable instructions, executable by a
computing device, processor, or controller (e.g., control unit
101), for implementing specific logical functions or steps in the
process, and alternate implementations are included within the
scope of the embodiments described herein, in which functions may
be executed out of order from that shown or discussed, including
substantially concurrently or in reverse order, depending on the
functionality involved, as would be understood by those having
ordinary skill in the art.
[0043] It should be emphasized that the above-described
embodiments, are merely set forth for a clear understanding of the
principles of this disclosure. Many variations and modifications
may be made to the above-described embodiment(s) without
substantially departing from the spirit and principles of the
techniques described herein. All such modifications are intended to
be included herein within the scope of this disclosure and
protected by the following claims.
* * * * *