U.S. patent application number 14/757741 was filed with the patent office on 2017-06-29 for extending an operational lifetime of an internet of things (iot) device.
The applicant listed for this patent is Intel Corporation. Invention is credited to Mark Kelly, Keith Nolan.
Application Number | 20170188308 14/757741 |
Document ID | / |
Family ID | 59088556 |
Filed Date | 2017-06-29 |
United States Patent
Application |
20170188308 |
Kind Code |
A1 |
Nolan; Keith ; et
al. |
June 29, 2017 |
Extending an operational lifetime of an internet of things (IOT)
device
Abstract
A method and apparatus for extending an operational lifetime of
an Internet of Things (IoT) device. In an example apparatus
including the IoT device, the IoT device includes a communications
device configured to transmit a report from a message dispatcher
and a power monitor to monitor a reserve power level. An interval
adjuster controls the timing of the report based, at least in part,
on the reserve power level.
Inventors: |
Nolan; Keith; (Mullingar,
IE) ; Kelly; Mark; (Leixlip, IE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Intel Corporation |
Santa Clara |
CA |
US |
|
|
Family ID: |
59088556 |
Appl. No.: |
14/757741 |
Filed: |
December 23, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y02D 30/70 20200801;
H04L 43/106 20130101; Y02D 70/1262 20180101; Y02D 70/144 20180101;
H04W 52/0235 20130101; H04L 43/065 20130101; H04L 43/067 20130101;
Y02D 70/142 20180101; Y02D 70/22 20180101; H04W 52/0258
20130101 |
International
Class: |
H04W 52/02 20060101
H04W052/02; H04L 12/26 20060101 H04L012/26 |
Claims
1. An apparatus for extending an operational lifetime of an
Internet of Things (IoT) device, comprising the IoT device, wherein
the IoT device comprises: a communications device configured to
transmit a report from a message dispatcher; a power monitor to
monitor a reserve power level; and an interval adjuster to control
a timing of the report based, at least in part, on the reserve
power level.
2. The apparatus of claim 1, wherein the reserve power level
comprises a battery level.
3. The apparatus of claim 1, wherein the reserve power level
comprises a charging level from a charging device.
4. The apparatus of claim 1, comprising: a message constructor to
assemble the report; and the message dispatcher to send the report
to a coordinator.
5. The apparatus of claim 1, wherein the IoT device comprises: a
sensor interface that is coupled to a sensor; and the report
comprises: a value measured by the sensor; and a time stamp for the
value.
6. The apparatus of claim 1, comprising: an alert limit that
comprises a value for the reserve power level; and the report
comprises the reserve power level and a timestamp when the reserve
power level falls below the alert limit.
7. The apparatus of claim 1, wherein the IoT device comprises an
actuator interface that is coupled to an actuator.
8. The apparatus of claim 1, wherein the IoT device is in a mesh
network with a plurality of other IoT devices.
9. The apparatus of claim 1, wherein the communications device
comprises a wireless local area network (WLAN) transceiver.
10. The apparatus of claim 1, wherein the communications device
comprises a wireless wide area network (WWAN) transceiver.
11. A method for controlling a reporting interval in an
Internet-of-Things (IoT) device, comprising: monitoring a power
level for the IoT device; and adjusting an interval between a
transmission of two reports based, at least in part, on the power
level.
12. The method of claim 11, comprising increasing the interval when
a reserve battery level falls below a selected limit.
13. The method of claim 11, comprising increasing the interval when
a power level of a charging device falls below a selected
limit.
14. The method of claim 11, comprising: constructing a report; and
sending the report to a coordinator.
15. The method of claim 11, comprising: measuring a value from a
sensor interface; constructing a report comprising the value and a
timestamp for the measurement; and sending the report to a
coordinator.
16. The method of claim 11, comprising placing the IoT device in a
low power state when the power level falls below a selected
limit.
17. The method of claim 11, comprising storing a report in a local
storage when the power level is below a selected limit.
18. A non-transitory, machine readable medium comprising code to
direct a processor to: measure a value of a reserve power level for
an Internet of Things (IoT) device; and adjust a reporting interval
between a transmission of two reports based, at least in part, on
the value.
19. The non-transitory, machine readable medium of claim 18,
comprising code to direct the processor to: construct a report; and
send the report to a coordinator.
20. The non-transitory, machine readable medium of claim 18,
comprising code to direct the processor to save a report that has
not been sent.
21. An Internet of Things (IoT) device, comprising: a
communications device configured to transmit a report from a
message dispatcher; a power monitor to monitor a reserve power
level; and an interval adjuster to control the timing of the report
based, at least in part, on the reserve power level.
22. The IoT device of claim 21, wherein the reserve power level
comprises a battery level.
23. The IoT device of claim 21, wherein the reserve power level
comprises a charging level from a charging device.
24. The IoT device of claim 21, comprising: a message constructor
to assemble the report; and a message dispatcher to send the report
to a coordinator.
25. The IoT device of claim 21, wherein the IoT device comprises: a
sensor interface that is coupled to a sensor; and the report
comprises: a value measured by the sensor; and a time stamp for the
value.
Description
TECHNICAL FIELD
[0001] The present techniques relate generally to Internet of
Things (IoT) devices. More specifically the present techniques
relate to devices that can schedule messaging based on battery
power
BACKGROUND
[0002] It has been estimated that the Internet of Things (IoT) may
bring Internet connectivity to 50 billion devices by 2020. For
organizations, the fault management of these devices in terms of
detecting and diagnosing abnormal operations on specific devices
may be of great importance. Maximizing the operational lifetime and
uptime of the devices and their services may require the
intelligent use of operational data in the device. For example, as
devices may not be connected to power grids, controlling power
drains may be important to improve battery and device life.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 is a drawing of a cloud computing network in
communication with a number of Internet of Things (IoT) devices, at
least some of which are communicating with servers.
[0004] FIG. 2 is a block diagram of components that may be present
in an IoT device used for self-monitoring and event reporting.
[0005] FIG. 3 is a plot of battery level over a 72 hour period.
[0006] FIG. 4 is a plot of reporting interval over the 72 hour
period.
[0007] FIG. 5 is plot of battery level indicating reporting
events.
[0008] FIG. 6 is a plot of reporting interval versus battery
life.
[0009] FIG. 7 is a process flow diagram of a method for controlling
a reporting interval based on battery level.
[0010] FIG. 8 is a block diagram of a non-transitory, machine
readable medium including code to direct a processor to control a
reporting interval for an IoT device based on a battery level.
[0011] The same numbers are used throughout the disclosure and the
figures to reference like components and features. Numbers in the
100 series refer to features originally found in FIG. 1; numbers in
the 200 series refer to features originally found in FIG. 2; and so
on.
DESCRIPTION OF THE EMBODIMENTS
[0012] The internet of things (IoT) is a concept in which a large
number of computing devices are interconnected to each other and to
the Internet to provide functionality and data acquisition at very
low levels. For example, IoT networks may include commercial and
home automation devices, such as traffic control systems, water
distribution systems, electric power distribution systems, pipeline
control systems, plant control systems, light switches,
thermostats, locks, cameras, alarms, motion sensors, and the like.
These devices, termed IoT devices herein, may be accessible through
remote computers, servers, and other systems, for example, to
control systems or access data.
[0013] In addition to network loading, many of the IoT devices may
have limited resources, e.g., with constraints on their memory
size, computing power, communication capabilities, and available
power, among others. The operating lifetime and uptime of an IoT
device may be adversely affected by these issues due to
insufficient memory and storage space, overheating, lack of power,
and loss of connectivity, among others.
[0014] The transmission of messages from the wireless IoT device to
a coordinator, such as a gateway or core network, is an important
function of a wireless IoT device. As an example, instrumentation
software packages in IoT devices generally report data on regular
intervals during normal operation. The IoT device may be located in
a high importance area, such as a traffic monitoring and control
system. Accordingly, the IoT device should operate for as long as
possible on its own power source.
[0015] In power constrained IoT sensor devices, sending data, for
example, through a wireless transceiver, may consume a large part
of the available energy budget. Further, a power constrained IoT
device may use an intermittently powered charging device, such as a
solar panel, a wind turbine, or a water turbine, to charge a
battery. As these devices may provide potentially dynamic and
volatile energy levels, communicating data while balancing the
available reserve power may be a challenge.
[0016] The techniques described herein may address the current
deficiencies by enabling the IoT devices to dynamically adapt the
rate of energy usage in accordance to the available energy
remaining. Accordingly, IoT devices may monitor resources and
control certain actions, such as intervals between dispatching
reports, reading sensors, performing calculations, and the like, to
decrease the probability of resource exhaustion issues. The
operating lifetime of power constrained IoT devices may be extended
by automatically adapting the rate at which energy intensive tasks
are scheduled based, at least in part, on the available reserve
power.
[0017] In one embodiment, periodic measurements of the available
battery power may be used to dynamically vary the intervals between
the sending of reports. For example, an exponential function may be
used to increase the interval between reports as the reserve power
levels decrease.
[0018] FIG. 1 is a drawing of a cloud computing network 100 in
communication with a number of Internet of Things (IoT) devices
102, at least some of which are communicating with servers 104. The
cloud computing network 100 may represent the Internet, or may be a
wide area network, such as a proprietary network for a company. The
IoT devices 102 may include any number of different types of
devices, grouped in various combinations. For example, a pipeline
group 106 may include IoT devices 102 along pipelines that are in
communication with the cloud computing network 100 through a
sub-network 108, such as a local area network, wireless local area
network, and the like. The IoT devices 102 in the pipeline group
106 may communicate with a server 104 through the cloud computing
network 100.
[0019] Other groups of IoT devices 102 may include remote weather
stations 109, local information terminals 110, alarm systems 112,
automated teller machines 114, and alarm panels 116, among many
others. Each of these IoT devices 102 may be in communication with
other IoT devices 102, with servers 104, or both. The IoT devices
102 may use another IoT device 102 as a constrained gateway 118 to
communicate with the cloud.
[0020] In addition, many of the IoT devices 102 may be located in
remote or outdoor sites, making access to power grids inconvenient
or expensive. For example, the IoT devices 102 of the pipeline
group 106 may be located along a pipeline that travels for many
miles through rural areas. Weather stations 109 may also be located
in rural or relatively inaccessible locations, such as mountaintops
or unmanned platforms. Accordingly, the IoT devices 102 may use
environmentally powered devices, such as solar panels, wind
turbines and the like, to maintain a charge in a battery and power
the unit. The battery may keep the device functioning during
periods when the environmentally powered charging device is not
functioning, such as after dark or in cloudy conditions for solar
panels.
[0021] However, as described herein, the operating lifetime of
power constrained IoT devices 102 may be reduced if the rate at
which energy intensive tasks are perform remains constant. However,
reporting data consumes power for transmission of packets, for
example, to establish and maintain network communications. If the
reserve power levels in the IoT device is low, the regular
reporting of data may exhaust the remaining power, forcing a
shutdown.
[0022] Accordingly, having an IoT device 102 that adjusts the
interval for sending reports, or other energy-intensive tasks,
based on the reserve power level may extend the operational
lifespan of the IoT device 102. Further, the adjustment may allow
the IoT device 102 to continue to provide reports for a longer
period of time before the reserve power level drops below
operational limits.
[0023] FIG. 2 is a block diagram of components that may be present
in an IoT device 200 used for self-monitoring and event reporting.
Like numbered items are as described with respect to FIG. 1. The
IoT device 200 may include any combinations of the components. The
components may be implemented as ICs, portions thereof, discrete
electronic devices, or other modules, logic, hardware, software,
firmware, or a combination thereof adapted in the IoT device 200,
or as components otherwise incorporated within a chassis of a
larger system. The block diagram of FIG. 2 is intended to show a
high level view of components of the IoT device 200. However, some
of the components shown may be omitted, additional components may
be present, and different arrangement of the components shown may
occur in other implementations. The IoT device 200 may be a traffic
monitor, a remote weather station, a programmable logic controller
(PLC) or remote terminal unit (RTU) in a SCADA (supervisory control
and data acquisition) network, an alarm system device, a smart
television, a cellular telephone, or any number of other IoT
devices 102 as discussed with respect to FIG. 1.
[0024] As seen in FIG. 2, the IoT device 200 may include a
processor 202, which may be a microprocessor, a multi-core
processor, a multithreaded processor, an ultra-low voltage
processor, an embedded processor, or other known processing
element. The processor 202 may be a part of a system on a chip
(SoC) in which the processor 202 and other components are formed
into a single integrated circuit, or a single package. As an
example, the processor 202 may include an Intel.RTM. Architecture
Core.TM. based processor, such as a Quark.TM.an Atom.TM., an i3, an
i5, an i7, or MCU-class processors, or another such processor
available from Intel.RTM. Corporation, Santa Clara, Calif. However,
other low power processors may be used, such as available from
Advanced Micro Devices, Inc. (AMD) of Sunnyvale, Calif., a
MIPS-based design from MIPS Technologies, Inc. of Sunnyvale,
Calif., an ARM-based design licensed from ARM Holdings, Ltd. or
customer thereof, or their licensees or adopters. These processors
may include units such as an A5/A6 processor from Apple.RTM. Inc.,
a Snapdragon.TM. processor from Qualcomm.RTM. Technologies, Inc.,
or an OMAP.TM. processor from Texas Instruments, Inc.
[0025] The processor 202 may communicate with a system memory 204.
Any number of memory devices may be used to provide for a given
amount of system memory. As examples, the memory can be random
access memory (RAM) in accordance with a Joint Electron Devices
Engineering Council (JEDEC) low power double data rate
(LPDDR)-based design such as the current LPDDR2 standard according
to JEDEC JESD 209-2E (published April 2009), or a next generation
LPDDR standard, for example, LPDDR3 or LPDDR4 that extends LPDDR2
to increase bandwidth, among others. In various implementations the
individual memory devices may be of any number of different package
types such as single die package (SDP), dual die package (DDP) or
quad die package (Q17P). These devices, in some embodiments, may be
directly soldered onto a motherboard to provide a lower profile
solution, while in other embodiments the devices are configured as
one or more memory modules that in turn couple to the motherboard
by a given connector. Any number of other memory implementations
may be used, such as other types of memory modules, e.g., dual
inline memory modules (DIMMs) of different varieties including but
not limited to microDlMMs or MiniDIMMs. For example, a memory may
be sized between 2GB and 16GB, and may be configured as a DDR3LM
package or an LPDDR2 or LPDDR3 memory, which is soldered onto a
motherboard via a ball grid array (BGA).
[0026] To provide for persistent storage of information such as
data, applications, one or more operating systems and so forth, a
mass storage 206 may also couple to the processor 202. To enable a
thinner and lighter system design the mass storage may be
implemented via a solid state disk drive (SSDD). However, the mass
storage may be implemented using a micro hard disk drive (HDD) in
some IoT devices 200. Further, any number of new technologies may
be used for the mass storage 206 in addition to, or instead of, the
technologies described, such resistance change memories, phase
change memories, holographic memories, or chemical memories, among
others. For example, the IoT device 200 may incorporate the 3D
XPOINT memories from Intel and Micron. The mass storage 206 may be
combined with the memory 204 in some embodiments.
[0027] The components may communicate over a bus 208. The bus 208
may include any number of technologies, including industry standard
architecture (ISA), extended ISA (EISA), peripheral component
interconnect (PCI), peripheral component interconnect extended
(PCIx), PCI express (PCIe), or any number of other technologies.
The bus 208 may be a proprietary bus, for example, used in a SoC
based system. Other bus systems may be used, such as the I2C
interface, SPI interfaces, and point to point interfaces, among
others.
[0028] The bus 208 may couple the processor 202 to an interface 210
that is used to connect external devices. The external devices may
include sensors 212, such as traffic sensors, flow sensors,
temperature sensors, motion sensors, wind speed sensors, pressure
sensors, barometric pressure sensors, and the like. The interface
210 may be used to connect the IoT device 200 to actuators 214,
such as traffic lights, traffic cameras, cameras, valve actuators,
lock solenoids, audible sound generators, visual warning devices,
and the like.
[0029] While not shown, various input/output (I/O) devices may be
present within, or connected to, the IoT device 200. For example, a
display may be included to show information, such as sensor
readings or actuator position. An input device, such as a touch
screen or keypad may be included to accept input.
[0030] The IoT device 200 can communicate with a computing cloud
computing network 100 in a variety of manners, including
wirelessly. In the embodiment shown in FIG. 2, various wireless
modules, each of which can correspond to a radio configured for a
particular wireless communication protocol, may be present. As used
herein a cloud computing network 100 may be a wide area network,
the Internet, or any number of other computing networks. As seen in
FIG. 2, a wireless local area network (WLAN) transceiver 216 may be
used to implement WiFi.TM. communications in accordance with the
Institute of Electrical and Electronics Engineers (IEEE) 802.11
standard, among others. In addition, wireless wide area
communications, e.g., according to a cellular or other wireless
wide area protocol, such as CDMA, LTE, GSM, and the like, can occur
via a wireless wide area network (WWAN) transceiver 218. The IoT
device 200 is not limited to these types of radio transceivers, but
may include any number of other radio communications equipment,
such as transceivers compatible with the Bluetooth.RTM. standard as
defined by the Bluetooth.RTM. special interest group. For example,
the IoT device 200 may communicate over a wireless personal area
network (WPAN) according to the IEEE 802.15.4 standard, among
others.
[0031] The IoT device 200 may include a network interface
controller (NIC) 220 to communicate with the cloud computing
network 100 through an Ethernet interface. This may include
communicating through a small wired network shared by number of IoT
devices 200 that communicate with the cloud computing network 100
through a constrained gateway 118, as described with respect to
FIG. 1. For example, the IoT device 200 may be part of an ad-hoc or
mesh network in which a number of devices pass communications
directly between each other, for example, following the optimized
link state routing (OLSR) Protocol, or the better approach to
mobile ad-hoc networking (B.A.T.M.A.N.), among others. The mesh
network communicate with the cloud through the constrained gateway
118.
[0032] The IoT device 200 may be powered by a local power source,
such as a rechargeable battery 222. The local power source may
include a charging device 224 that may include solar cells, wind
turbines, water turbines, or other environmentally powered devices.
The charging device 224 may charge the rechargeable battery 222 to
power the IoT device 200 when power from the charging device 224 is
not available, such as after dark or in low wind speeds. A charging
interface 226 may monitor the charging device 224 to determine when
power from the charging device 224 is available. As shown in FIG.
2, if multiple IoT devices 200 are present, the charging device 224
may be used to charge batteries in each of the devices. As
described herein, this may also be used to share power among the
IoT devices 200 during periods of low power generation.
[0033] The charging device 224 is not limited to an environmentally
powered system, but may include a charging device 224 that is
coupled to a power grid. In this embodiment, the rechargeable
battery 222 may be used as a backup to keep the system operational
during failures of power and equipment.
[0034] As an example, an IoT device 200 may use up to 160 mA to
transmit a report using an 868 MHz mesh networking transceiver. The
IoT device 200 may consume only 55 uA in a sleep state. If the IoT
device 200 uses a 6600 mAh rechargeable battery 222 and a solar
powered charging device 224 that can supply up to 200 mA to
maximize the operating lifetime, management of the energy demands,
such as the interval between reports, may be important.
[0035] The mass storage 206 may include a number of modules to
implement the self-monitoring functions described herein. These
modules may include a power monitor 228 that monitors reserve power
levels in the rechargeable battery 222, charging status from the
charging device 224, and power drains, such as power usage when
transmitting reports, among others. The power monitor 228 may be
part of a system monitor that compares operational parameters to
alert limits to determine when an alert message should be sent. The
comparison may include determining when a trend indicates a breach
of an alert limit may occur, such as determining that reserve power
levels are decreasing, for example, due to lack of power from the
charging device 224, predicting when the reserve power level will
cross an alert limit, and sending out an alert message. Further,
the system monitor may compare multiple operational parameters to
determine when to send an alert message, for example, varying an
alert limit based on another parameter. For example, the system
monitor may use a temperature reading to determine when to send an
alert message on a reserve capacity in the rechargeable battery
222. During colder temperatures, the alert message may be sent out
at a higher reserve capacity level, as the rechargeable battery 222
may discharge faster under cold temperatures.
[0036] An interval adjuster 230 may set the interval between energy
demanding actions, such as sending reports, taking measurements,
and the like. The interval adjuster 230 may set the interval
between actions based on the reserve power level in the
rechargeable battery 222, the operation status of the charging
device 224, or a combination of the two, among other parameters.
For example, ambient temperature may be taken into account to
adjust intervals between actions. During colder temperatures, the
interval adjuster 230 may increase the interval between reports at
a higher reserve power level, as the rechargeable battery 222 may
discharge faster under cold temperatures.
[0037] A message constructor 232 may be used to assemble the
reports, including both standard sensor readings and alert
messages. Among other information, the reports may include a
timestamp indicating when the measurement was taken, and a value
for the measurement. In the case of an alert message, the report
may include a timestamp indicating when the breach of the alert
limit took place and the reserve power level at the time the alert
limit was breached. If an alert limit is based on a rate of change
of an operational parameter, the message may include a predicted
time when the operational parameter may pass the alert limit.
[0038] A message dispatcher 234 may send the report to a
coordinator, which may be another IoT device 200, or may be a
server, a router, or other device. For example, the message
dispatcher 234 may place the report into a message queue for a
control system. Further, the message dispatcher 234 may use any
number of communication techniques in addition to, or instead of
the control system, such as sending the report in a text message to
a mobile device, placing an automated call to a phone number,
sending out an e-mail, and the like.
[0039] The IoT device 200 is not limited to including all of the
blocks shown in FIG. 2. For example, some IoT devices 200 may not
include the WLAN transceiver 216, or the NIC 220, such as in remote
applications. Other IoT devices 200 may merely monitor the reserve
power capacity in the rechargeable battery 222, without using a
separate charging interface 226 to monitor operations of a charging
device 224. Actuators 214 or sensors 212 may not be included if the
IoT device 200 is functioning as a coordinator or network gateway
for other IoT devices 200. Other units may be included in some
embodiments, such as integrated temperature sensors, touch screens,
displays, and the like.
[0040] The IoT device 200 may also include additional units not
shown in FIG. 2. For example, the IoT device 200 may be in a
location near other IoT devices 200, each using an individual
battery 222, such as a field processing system along a pipeline.
The battery 222 may be directly or indirectly coupled to the
batteries 222 of the other IoT devices 200, for example, through
the charging device 224. The IoT devices 200 may use the charging
interface 226 to control this interconnection and use power from
batteries 222 on other IoT devices 200. Thus, the IoT devices 200
may prioritize the functions of the IoT devices 200 to extend the
lifespan of the various IoT devices 200, while maintaining the most
important functions and communications. The lower priority IoT
devices 200 may be placed in lower power modes to allow higher
priority functions to continue.
[0041] In some examples, a sensor may use a separate battery from
the battery 222 in the IoT device 200. As described above, this
battery may be coupled to the battery 222 in the IoT device 200,
for example, through the charging interface. In this case, the
power monitor 228 may balance power usage among the sensing and
communication functions to extend the life of the IoT device 200,
while maintaining some level of sensing and communications.
[0042] FIG. 3 is a plot 300 of reserve power level 302 against time
304 over a 72 hour period for an IoT device. In the plot 300, it
can be seen that, outside of some power spikes upwards, the reserve
power level 302 is continuously dropping off. For example, a solar
panel that is used to recharge the battery may not be keeping up
with demand.
[0043] The IoT device may use this information to adapt its
operating behavior in accordance to the available power to maximize
its operating lifetime, e.g., to maintain operation overnight or to
allow some reporting even when the reserve power level 302 has
significantly dropped. One or more reserve power limits 306 may be
selected to control the reporting intervals for the IoT device. For
example, during a first period 308, the reserve power level 302 may
remain above the reserve power limit 306, allowing regular
reporting, as described with respect to FIG. 4. During a second
period 310, the reserve power level 302 has dropped to the reserve
power limit 306. During this period, reporting intervals, and
intervals between other high power demand activities, may be
extended to save energy. In a third period 312, the reserve power
level 302 has dropped below the reserve power limit 306, and
intervals may be further extended. The changes can be see for the
reporting intervals in FIG. 4.
[0044] FIG. 4 is a plot of reporting interval 402 against time 304
over the 72 hour period. Like numbered items are as described with
respect to FIG. 3. As the plot reflect a real world case, the
intervals are measured from the perspective of a receiving device
or coordinator in a mesh network. Thus, the sporadic large
increases in intervals are due to failed scheduled reporting
attempts.
[0045] As described with respect to FIG. 3, the intervals may
depend on the available battery power level. In the first period
308, regularly scheduled reports are sent, with an occasional
longer interval, e.g., intervals 404, due to failed reporting
attempts. Once the reserve power level 302, has fallen to or below
the reserve power limit 306, for example, in periods 310 and 312,
the intervals may be increased to save battery life. As the reserve
power level 302 increases, the reporting intervals may be
decreased, as illustrated with respect to FIG. 5.
[0046] FIG. 5 is plot 502 of battery level 504 against time 506,
indicating reporting events, which are shown as tick marks 508. To
simplify the drawing, not all tick marks 508 are labeled. Like
numbered items are as described with respect to FIG. 3. The spacing
between the tick marks 508 on the plot 502 denotes the reporting
interval. At a lower power level 510, the intervals are further
apart than at a higher battery level 512. In this illustration,
there may be a reserve power limit 306 between the lower power
level 510 and the higher power level 512, which allows as
incremental decrease in reporting interval. However, the reporting
interval, or the interval between sequential power drawing events,
does not have to be controlled by a single or even a few limits,
but may be a function, as described with respect to FIG. 6.
TABLE-US-00001 TABLE 1 Table of example battery level versus
intervals between tasks Battery (%) Interval (mins) >=94 2 86 3
79 4 71 5 63 6 56 7 48 8 40 9 32 11 25 13 17 15 9 19 2 23 <2
1440
[0047] FIG. 6 is a plot 602 of reporting interval 604 against
available battery power 606, illustrating a control function that
may be used to adjust reporting intervals. It may be understood
that similar functions may be used to adjust the interval between
other energy intensive functions. As shown by the plot 602, the
intervals 604 are inversely proportional to the available battery
power 606. The power profile shown by the plot 602 is derived from
a log process and may enable an IoT device to vary its reporting
intervals from a minimum reporting interval of 2 mins and a maximum
of 23 mins. Table 1 presents a numerical chart of example battery
level versus reporting intervals. Table 1 also shows an additional
interval state of 24 hrs for when the device power level is less
than 2%. This longer interval may allow the device to recharge,
which may reduce the number of occurrences of deep discharge states
in order to avoid battery life shortening.
[0048] FIG. 7 is a process flow diagram of a method 700 for
controlling a reporting interval based on battery level. The method
700 starts at block 702, for example, when the IoT device is
powered, or a battery conservation method is activated. At block
704, the IoT device measures the available reserve power level.
This can be performed via a system call to measure the battery
voltage using an analog to digital converter. The reserve power
level can be calculated dividing the measured battery level against
the rated voltage level and multiplying the result by 100 to obtain
a percentage value.
[0049] At block 706, an interval for the action, such as the
reporting interval, is selected based on the measured battery
level. For example, the reporting interval may be derived from the
power profile depicted in FIG. 6 and Table 1. At block 708, the
intended operation, e.g., send a report of a sensor observation
using wireless communications.
[0050] At block 710, a sleep or suspend state may be activated for
the selected interval to preserve power and to allow for battery
recharging, for example, if the prevailing conditions allow for
adequate power to be generated. Deep discharging rechargeable
batteries significantly shortens their lifetime. The system is
designed to prevent power constrained IoT device batteries from
reaching a deep discharge state, e.g., placing the IoT device in a
24 hour sleep state to allow for self-recharging when the available
battery level reaches a critical lower threshold.
[0051] At block 712, a check to see if the system should continue.
Typically, in embedded IoT devices, the operation continues
indefinitely, e.g., process flow returns to block 704.
[0052] Existing power constrained IoT sensors operating on a fixed
interval or scheduled basis would continue to attempt to operate on
this schedule until the available battery resources are exhausted.
Fixed strategy approaches, e.g., fast interval reporting or slow
interval reporting are not optimal either; the former can
significantly reduce the operating lifetime of the device and the
latter may be reporting too infrequently to capture important
sensor measurement events.
[0053] FIG. 8 is a block diagram of a non-transitory, machine
readable medium 800 including code to direct a processor 802 to
control a reporting interval for an IoT device based on a battery
level. The processor 802 may access the code over a bus 804, as
described herein. The non-transitory, machine readable medium 800
may include code 806 to direct the processor 802 to measure a
reserve power level, including, for example, whether a charging
device is operational and providing current to a battery. Code 808
may be included to direct the processor 802 to adjust an interval
between actions, such as reporting a message to a coordinator. Code
810 may be included to direct the processor 802 to construct a
reporting message, for example, including a sensor measurement and
a timestamp, among others. Further, code 810 may be included to
direct the processor 802 to dispatch the reporting message to a
coordinator, such as a gateway or control server. If the reserve
power level is too low to dispatch frequent messages, but sensor
observations may still be taken, code 814 may be included to direct
the processor 802 to save unsent messages to be sent when power
levels permit.
EXAMPLES
[0054] Example 1 includes an apparatus for extending an operational
lifetime of an Internet of Things (IoT) device, including the IoT
device. The IoT device includes a communications device configured
to transmit a report from a message dispatcher, a power monitor to
monitor a reserve power level, and an interval adjuster to control
a timing of the report based, at least in part, on the reserve
power level.
[0055] Example 2 includes the subject matter of example 1, wherein
the reserve power level includes a battery level.
[0056] Example 3 includes the subject matter of examples 1 or 2,
wherein the reserve power level includes a charging level from a
charging device.
[0057] Example 4 includes the subject matter of any of examples 1
to 3, including: a message constructor to assemble the report; and
a message dispatcher to send the report to a coordinator.
[0058] Example 5 includes the subject matter of any of examples 1
to 4, wherein the IoT device includes: a sensor interface that is
coupled to a sensor; and the report includes: a value measured by
the sensor; and a time stamp for the value.
[0059] Example 6 includes the subject matter of any of examples 1
to 5, including: an alert limit that includes a value for the
reserve power level; and the report includes the reserve power
level and a timestamp when the reserve power level falls below the
alert limit.
[0060] Example 7 includes the subject matter of any of examples 1
to 6, wherein the IoT device includes an actuator interface that is
coupled to an actuator.
[0061] Example 8 includes the subject matter of any of examples 1
to 7, wherein the IoT device is in a mesh network with a plurality
of other IoT devices.
[0062] Example 9 includes the subject matter of any of examples 1
to 8, wherein the communications device includes a wireless local
area network (WLAN) transceiver.
[0063] Example 10 includes the subject matter of any of examples 1
to 9, wherein the communications device includes a wireless wide
area network (WWAN) transceiver.
[0064] Example 11 provides a method for controlling a reporting
interval in an Internet-of-Things (IoT) device, including:
monitoring a power level for the IoT device; and adjusting an
interval between a transmission of two reports based, at least in
part, on the power level.
[0065] Example 12 includes the subject matter of example 11,
including increasing the interval when a reserve battery level
falls below a selected limit.
[0066] Example 13 includes the subject matter of examples 11 or 12,
including increasing the interval when a power level of a charging
device falls below a selected limit.
[0067] Example 14 includes the subject matter of any of examples 11
to 13, including: constructing a report; and sending the report to
a coordinator.
[0068] Example 15 includes the subject matter of any of examples 11
to 14, including: measuring a value from a sensor interface;
constructing a report including the value and a timestamp for the
measurement; and sending the report to a coordinator.
[0069] Example 16 includes the subject matter of any of examples 11
to 15, including placing the IoT device in a low power state when
the power level falls below a selected limit.
[0070] Example 17 includes the subject matter of any of examples 11
to 16, including storing a report in a local storage when the power
level is below a selected limit.
[0071] Example 18 provides a non-transitory, machine readable
medium including code to direct a processor to: measure a value of
a reserve power level for the an Internet of Things (IoT) device;
and adjust a reporting interval between a transmission of two
reports based, at least in part, on the value.
[0072] Example 19 includes the subject matter of example 18,
including code to direct a processor to: construct a report; and
send the report to a coordinator.
[0073] Example 20 includes the subject matter of examples 18 or 19,
including code to direct a processor to save a report that has not
been sent.
[0074] Example 21 provides an Internet of Things (IoT) device,
including: a communications device configured to transmit a report
from a message dispatcher; a power monitor to monitor a reserve
power level; and an interval adjuster to control the timing of the
report based, at least in part, on the reserve power level.
[0075] Example 22 includes the subject matter of example 21,
wherein the reserve power level includes a battery level.
[0076] Example 23 includes the subject matter of examples 21 or 22,
wherein the reserve power level includes a charging level from a
charging device.
[0077] Example 24 includes the subject matter of any of examples 21
to 23, including: a message constructor to assemble the report; and
a message dispatcher to send the report to a coordinator.
[0078] Example 25 includes the subject matter of any of examples 21
to 24, wherein the IoT device includes: a sensor interface that is
coupled to a sensor; and the report includes: a value measured by
the sensor; and a time stamp for the value.
[0079] Example 26 includes the subject matter of any of examples 21
to 25, including: an alert limit that includes a value for the
reserve power level; and the report includes the reserve power
level and a timestamp when the reserve power level falls below the
alert limit.
[0080] Example 27 includes the subject matter of any of examples 21
to 26, wherein the IoT device includes an actuator interface that
is coupled to an actuator.
[0081] Example 28 includes the subject matter of any of examples 21
to 27, wherein the communications device includes a wireless local
area network (WLAN) transceiver.
[0082] Example 29 includes the subject matter of any of examples 21
to 28, wherein the communications device includes a wireless wide
area network (WWAN) transceiver.
[0083] Example 30 includes an apparatus for extending an
operational lifetime of an Internet of Things (IoT) device,
including the IoT device, wherein the IoT device includes a means
for controlling a timing for sending of a report based, at least in
part, on a reserve power level.
[0084] Example 31 includes the subject matter of example 30,
wherein the IoT device includes a means for transmitting the
report.
[0085] Example 32 includes the subject matter of example 30 or 31,
wherein the IoT device includes a means for monitoring the reserve
power level.
[0086] Example 33 includes the subject matter of any of examples 30
to 32, wherein the apparatus includes a means for increasing a
reserve power level.
[0087] Example 34 includes the subject matter of any of examples 30
to 33, wherein the IoT device includes a means for assembling the
report.
[0088] Example 35 includes the subject matter of any of examples 30
to 34, wherein the IoT device includes a means for measuring an
environmental variable.
[0089] Example 36 includes the subject matter of any of examples 30
to 35, wherein the IoT device includes a means for affecting an
environmental change.
[0090] Example 37 includes the subject matter of any of examples 30
to 36, wherein the IoT device includes a means for interacting in a
mesh network with a plurality of other IoT devices.
[0091] Some embodiments may be implemented in one or a combination
of hardware, firmware, and software. Some embodiments may also be
implemented as instructions stored on a machine-readable medium,
which may be read and executed by a computing platform to perform
the operations described herein. A machine-readable medium may
include any mechanism for storing or transmitting information in a
form readable by a machine, e.g., a computer. For example, a
machine-readable medium may include read only memory (ROM); random
access memory (RAM); magnetic disk storage media; optical storage
media; flash memory devices; or electrical, optical, acoustical or
other form of propagated signals, e.g., carrier waves, infrared
signals, digital signals, or the interfaces that transmit and/or
receive signals, among others.
[0092] An embodiment is an implementation or example. Reference in
the specification to "an embodiment," "one embodiment," "some
embodiments," "various embodiments," or "other embodiments" means
that a particular feature, structure, or characteristic described
in connection with the embodiments is included in at least some
embodiments, but not necessarily all embodiments, of the
techniques. The various appearances of "an embodiment", "one
embodiment", or "some embodiments" are not necessarily all
referring to the same embodiments. Elements or aspects from an
embodiment can be combined with elements or aspects of another
embodiment.
[0093] Not all components, features, structures, characteristics,
etc. described and illustrated herein need be included in a
particular embodiment or embodiments. If the specification states a
component, feature, structure, or characteristic "may", "might",
"can" or "could" be included, for example, that particular
component, feature, structure, or characteristic is not required to
be included. If the specification or claim refers to "a" or "an"
element, that does not mean there is only one of the element. If
the specification or claims refer to "an additional" element, that
does not preclude there being more than one of the additional
element.
[0094] It is to be noted that, although some embodiments have been
described in reference to particular implementations, other
implementations are possible according to some embodiments.
Additionally, the arrangement and/or order of circuit elements or
other features illustrated in the drawings and/or described herein
need not be arranged in the particular way illustrated and
described. Many other arrangements are possible according to some
embodiments.
[0095] In each system shown in a figure, the elements in some cases
may each have a same reference number or a different reference
number to suggest that the elements represented could be different
and/or similar. However, an element may be flexible enough to have
different implementations and work with some or all of the systems
shown or described herein. The various elements shown in the
figures may be the same or different. Which one is referred to as a
first element and which is called a second element is
arbitrary.
[0096] The techniques are not restricted to the particular details
listed herein. Indeed, those skilled in the art having the benefit
of this disclosure will appreciate that many other variations from
the foregoing description and drawings may be made within the scope
of the present techniques. Accordingly, it is the following claims
including any amendments thereto that define the scope of the
techniques.
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