FAQ

Frequently Asked Questions

•  Why are you making a battery charger?

•  Why are you mounting it on a bike?

•  What is a dynamo?

•  Why did you 3D print?

•  Why are you incorporating gears?

•  Why is there an internal rib design?

•  Is it capable of charging all phones?

•  Why did you choose to use a pre-made motor/generator?

 

 

•  Why are you making a battery charger? 

  Our group was initially given a selection of general project topics we were allowed to pursue. We decided that designing a battery charger both interested us, and would allow us to explore an area of engineering none of us are majoring in. 

•  Why are you mounting it on a bike?

  In order to generate a steady source of electricity for battery charging, we needed a mechanical mechanism that produced a large number of rotations

•  What is a dynamo?

  A dynamo is an electric generator. It takes mechanical energy in the form of movement and converts it into electrical energy. A more in depth look at what a dynamo is and how it functions can be found in the Exterior Sources portion of this blog.
  

•  Why did you 3D print?

  Our group decided to 3D print the structural portions of our project. This includes ribs within the dynamo to support the gear train, the shell of the dynamo itself (the dynamo in this case actually being the entire apparatus containing the electric generator), and the custom phone holder. 3D printing allows for a relatively quick turn around, ability to make changes to designs, and it allows for complex shapes necessary for the design of the apparatus.
  

•  Why are you incorporating gears?

  In order to output enough electricity (high enough Volts and Amps) to charge a cellphone, we need to turn our motor at a high RPM (our motor is rated at 17,000 RPM unloaded at an input of 6V). With a bike traveling at 5 mph, our gear chain is capable of turning our motor at about 18,000 RPM, which should be high enough to charge any phone when connected to our electrical system.
  

•  Why is there an internal rib design?

  The rib design is necessary within the dynamo as it supports the gear train.
  

•  Is it capable of charging all phones?

  Yes, our system is set up with multiple capacitors, a 5 volt regulator, and a female USB port. The majority of phones currently use a two part charging system consisting of a male USB cord to a connector specific to the phone itself, plus a 5V converter to take the standard 120V coming from a wall outlet and lower it enough so the phone can handle it. Our system removes the need for the converter and accepts any male USB.
  

•  Why did you choose to use a pre-made motor/generator?

  While it would have been possible for our group to make our own generator, we felt it would be more cost efficient, reliable, and safer to use a pre-made motor.