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An ultra-low power wireless sensor network for bicycle torque performance measurements.

Gharghan SK, Nordin R, Ismail M - Sensors (Basel) (2015)

Bottom Line: The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol.The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered.The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, UKM Bangi, Selangor 43600, Malaysia. sadiq@siswa.ukm.edu.my.

ABSTRACT
In this paper, we propose an energy-efficient transmission technique known as the sleep/wake algorithm for a bicycle torque sensor node. This paper aims to highlight the trade-off between energy efficiency and the communication range between the cyclist and coach. Two experiments were conducted. The first experiment utilised the Zigbee protocol (XBee S2), and the second experiment used the Advanced and Adaptive Network Technology (ANT) protocol based on the Nordic nRF24L01 radio transceiver chip. The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol. In addition, an analytical model was derived to correlate the sensor node average current consumption with a crank arm cadence. The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered. The achievable communication range was 65 and 50 m for ZigBee and ANT, respectively, during measurement on an outdoor cycling track (i.e., velodrome). The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach.

No MeSH data available.


Related in: MedlinePlus

Average current consumption of each component in the torque sensor node as a function of bicycle cadence by applying the sleep/wake algorithm.
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sensors-15-11741-f018: Average current consumption of each component in the torque sensor node as a function of bicycle cadence by applying the sleep/wake algorithm.

Mentions: The average current consumption of each component and the average total current consumption of the torque sensor node were computed based on current measurements in active and sleep modes and Equation (16). The results are shown in Figure 18 for different bicycle cadences on the basis of the application of the sleep/wake algorithm during the crank arm rotation. This figure shows that the most power is dissipated in the strain gauge transducers and XBee S2 module, whereas a small amount of power is consumed by ANT. In contrast, the torque sensor node consumes more power when it uses the XBee S2 module compared with ANT. Figure 19 shows the power savings of the torque sensor node based on ANT relative to XBee S2 for cadence range. This figure shows that the power saving increases with cadence because the total average current consumption of the XBee S2 module increases with cadence, whereas the total average current consumption increases slightly when ANT is used. The obtained power savings are 31% and 35% for cadences of 100 and 160 RPM, respectively. As expected, the power saving in this case is less than in the first case (i.e., the case in Subsection 5.3). This outcome occurred because in the first case, the average current consumption computation was achieved based on RF modules alone, whereas for this case, the computation was performed based on sharing all the components of the sensor node. Figure 20 shows the estimated battery lifetime of the torque sensor node with the used battery capacity for the two wireless technologies for three cases: (I) operation without the sleep/wake algorithm (i.e., conventional operation); (II) operation of the sleep/wake algorithm at 100 RPM; and (III) operation of the sleep/wake algorithm at 160 RPM. The battery lifetime of the torque sensor node was prolonged to 529 h in the second and third cases when the ANT module was used in the sensor node, noting that the battery capacity is 3.7 V/1000 mAh, whereas the battery lifetime was 364 and 341 h for 100 and 160 RPM, respectively when the XBee S2 module is used. The battery life in the first case (i.e., conventional operation) was 89 and 58 h for the ANT and XBee S2 modules, respectively, which is significantly less than that of the second and third cases. The above results indicated that the ANT protocol is more convenient for the torque sensor node in terms of power consumption.


An ultra-low power wireless sensor network for bicycle torque performance measurements.

Gharghan SK, Nordin R, Ismail M - Sensors (Basel) (2015)

Average current consumption of each component in the torque sensor node as a function of bicycle cadence by applying the sleep/wake algorithm.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4481893&req=5

sensors-15-11741-f018: Average current consumption of each component in the torque sensor node as a function of bicycle cadence by applying the sleep/wake algorithm.
Mentions: The average current consumption of each component and the average total current consumption of the torque sensor node were computed based on current measurements in active and sleep modes and Equation (16). The results are shown in Figure 18 for different bicycle cadences on the basis of the application of the sleep/wake algorithm during the crank arm rotation. This figure shows that the most power is dissipated in the strain gauge transducers and XBee S2 module, whereas a small amount of power is consumed by ANT. In contrast, the torque sensor node consumes more power when it uses the XBee S2 module compared with ANT. Figure 19 shows the power savings of the torque sensor node based on ANT relative to XBee S2 for cadence range. This figure shows that the power saving increases with cadence because the total average current consumption of the XBee S2 module increases with cadence, whereas the total average current consumption increases slightly when ANT is used. The obtained power savings are 31% and 35% for cadences of 100 and 160 RPM, respectively. As expected, the power saving in this case is less than in the first case (i.e., the case in Subsection 5.3). This outcome occurred because in the first case, the average current consumption computation was achieved based on RF modules alone, whereas for this case, the computation was performed based on sharing all the components of the sensor node. Figure 20 shows the estimated battery lifetime of the torque sensor node with the used battery capacity for the two wireless technologies for three cases: (I) operation without the sleep/wake algorithm (i.e., conventional operation); (II) operation of the sleep/wake algorithm at 100 RPM; and (III) operation of the sleep/wake algorithm at 160 RPM. The battery lifetime of the torque sensor node was prolonged to 529 h in the second and third cases when the ANT module was used in the sensor node, noting that the battery capacity is 3.7 V/1000 mAh, whereas the battery lifetime was 364 and 341 h for 100 and 160 RPM, respectively when the XBee S2 module is used. The battery life in the first case (i.e., conventional operation) was 89 and 58 h for the ANT and XBee S2 modules, respectively, which is significantly less than that of the second and third cases. The above results indicated that the ANT protocol is more convenient for the torque sensor node in terms of power consumption.

Bottom Line: The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol.The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered.The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, UKM Bangi, Selangor 43600, Malaysia. sadiq@siswa.ukm.edu.my.

ABSTRACT
In this paper, we propose an energy-efficient transmission technique known as the sleep/wake algorithm for a bicycle torque sensor node. This paper aims to highlight the trade-off between energy efficiency and the communication range between the cyclist and coach. Two experiments were conducted. The first experiment utilised the Zigbee protocol (XBee S2), and the second experiment used the Advanced and Adaptive Network Technology (ANT) protocol based on the Nordic nRF24L01 radio transceiver chip. The current consumption of ANT was measured, simulated and compared with a torque sensor node that uses the XBee S2 protocol. In addition, an analytical model was derived to correlate the sensor node average current consumption with a crank arm cadence. The sensor node achieved 98% power savings for ANT relative to ZigBee when they were compared alone, and the power savings amounted to 30% when all components of the sensor node are considered. The achievable communication range was 65 and 50 m for ZigBee and ANT, respectively, during measurement on an outdoor cycling track (i.e., velodrome). The conclusions indicate that the ANT protocol is more suitable for use in a torque sensor node when power consumption is a crucial demand, whereas the ZigBee protocol is more convenient in ensuring data communication between cyclist and coach.

No MeSH data available.


Related in: MedlinePlus