Engineering

Activities

Resources

Enrichment Program

Summer School

Contact Us

 

Mechatronics Learning Studio

 

Power Generation Bike

Ghayath Housseini, Gabriel Mak, and Selmaan Qureshi, Mechanical Engineering, University of Ottawa
 

Objective

Our project is an exercise bike that can return power back to the power grid. The motivation for this project is the fact that power costs too much and that people lack motivation to exercise. With this project people will be motivated to exercise due to the fact that they would be reducing their power bill.

 Our prototype is a regular bicycle where the back wheel is lifted off the ground so the tire can spin freely. To the back a squirrel cage induction motor is attached. Using a pulley of 1 inch diameter on the motor, the wheel is able to spin the shaft. The motor spins at 3600 rpm at the highest gear ratio and in order to produce power the cyclist must pedal over 200 rpm at the bike wheel. With this setup the energy needed by cyclist to be able to produce power is really high.

To fix this problem we must put into consideration that when a regular bicycle is in motion on the road it is easier to pedal due to the fact that the human has momentum. This means that the inertia would remain much longer with a flywheel on the bike. When the bike is stationary it lacks that inertia effect so in order to fix that problem a flywheel needs to be added.

 

 

 

Materials

   Bike

   Squirrel cage induction motor

   Bike Tachometer

   Base to hold the bike

   Power meter

   Pulleys to adjust gear ratio

  Flywheel

 

Design Steps

Text Box: Supports for motor

 

Design a base which lifts the rear tire off the ground. The base should also support a motor with the shaft facing the wheel. 

 

 

 

Figure 1: Base attached to bike

Test that the back wheel can turn freely without any obstacles in the way

Attach the motor to the base and calculate the gear ratios to figure out what size pulley would be most suitable for the application.

 

Figure 2: Motor

 

Figure 3: Base with motor.

 

For more efficient production a flywheel should be placed on the motor (like in the picture) or if an exercise bike is used the wheel should already be a flywheel.

 To measure the rpm and the speed attach a tachometer/speedometer to the bike.

Figure 4: Bike set up.

Attach the power meter and the ammeter to be able to take measurements. In this picture for the current the wire

was wrapped three times to be able to get a reading. This means the displayed current is actually divided by 3

 

Figure 5: Ammeter

 

 Do some tests to ensure that when you are ready to take the results you know how fast you need to pedal to change the motor into a generator.

Using the Microwin program you can view the results and understand when you will be producing power.

Figure 6: Results from a trial.

Results

From our results it can be seen that the voltage is constant and the sinusoidal wave is not very contaminated. The current fluctuates due to the fact that the pedaling is not very steady. When the power factor is negative the biker is producing power.
 

Problems

Inefficiencies: position of biker, very little residual kinetic energy without flywheel, electrical losses.

Size of flywheel, gear ratio issues (only worked on highest gear).

Motor initially consumes power instead of generating it.