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Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.

Yang Y, Yeo J, Priya S - Sensors (Basel) (2012)

Bottom Line: Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement.It was able to generate power even during uphill riding which has never been shown with other approaches.Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

View Article: PubMed Central - PubMed

Affiliation: Biomedical Engineering, Chonbuk National University, Deokjin-dong Jeonju 664-14, Korea. ysyang@jbnu.ac.kr

ABSTRACT
Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

Show MeSH
The nonlinear electromagnetic energy harvester (a) structure; (b) 3-D CAD model for rapid prototyping.
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f3-sensors-12-10248: The nonlinear electromagnetic energy harvester (a) structure; (b) 3-D CAD model for rapid prototyping.

Mentions: We designed and implemented a nonlinear electromagnetic harvester using neodymium-boron strong magnets as shown in Figure 3. The moving magnet in the center position in Figure 3(a) oscillates left-and-right between the two end magnets. Repulsive forces between the center and end magnets maintain the certain equilibrium separation. We found that a 10 mm thickness for the center magnet was adequate to prevent it from rotating within the cylindrical cavity. The diagonal length of 22.4 mm in the vertical cross-section of the moving magnet ensures proper positioning inside the cylinder with inner diameter of 20.2 mm. Marin et al. [15,16] have shown that the stiffness terms in such an system can be estimated by fitting the computational data with a 5th order non-linear curve and the damping constant is on the order of 0.0994. There were four solenoid windings on the outer surface of the cylindrical body for electromagnetic energy conversion. The length of the cylinder was selected to be suitable for being mounted on the bicycle handlebar without any interference with the steering. The physical dimension and design parameters are shown in Table 1. The power generated across the coil is given as [15]:P=(Blz˙RL+Re)2RLwhere the quantity ż represents the relative displacement of the center magnet with respect to coil, RL is the load resistance, B is the magnetic field, l is the length of coil, and Re is the coil resistance.


Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.

Yang Y, Yeo J, Priya S - Sensors (Basel) (2012)

The nonlinear electromagnetic energy harvester (a) structure; (b) 3-D CAD model for rapid prototyping.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472826&req=5

f3-sensors-12-10248: The nonlinear electromagnetic energy harvester (a) structure; (b) 3-D CAD model for rapid prototyping.
Mentions: We designed and implemented a nonlinear electromagnetic harvester using neodymium-boron strong magnets as shown in Figure 3. The moving magnet in the center position in Figure 3(a) oscillates left-and-right between the two end magnets. Repulsive forces between the center and end magnets maintain the certain equilibrium separation. We found that a 10 mm thickness for the center magnet was adequate to prevent it from rotating within the cylindrical cavity. The diagonal length of 22.4 mm in the vertical cross-section of the moving magnet ensures proper positioning inside the cylinder with inner diameter of 20.2 mm. Marin et al. [15,16] have shown that the stiffness terms in such an system can be estimated by fitting the computational data with a 5th order non-linear curve and the damping constant is on the order of 0.0994. There were four solenoid windings on the outer surface of the cylindrical body for electromagnetic energy conversion. The length of the cylinder was selected to be suitable for being mounted on the bicycle handlebar without any interference with the steering. The physical dimension and design parameters are shown in Table 1. The power generated across the coil is given as [15]:P=(Blz˙RL+Re)2RLwhere the quantity ż represents the relative displacement of the center magnet with respect to coil, RL is the load resistance, B is the magnetic field, l is the length of coil, and Re is the coil resistance.

Bottom Line: Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement.It was able to generate power even during uphill riding which has never been shown with other approaches.Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

View Article: PubMed Central - PubMed

Affiliation: Biomedical Engineering, Chonbuk National University, Deokjin-dong Jeonju 664-14, Korea. ysyang@jbnu.ac.kr

ABSTRACT
Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

Show MeSH