Pedal-Powered Smartphone Charger

We designed a pedal-powered phone charger from old bike parts and drill components. This makes it possible for simultaneous exercise and charging of a cellular device. This invention combines the maintenance of physical and energy-related well-being, conserving a building's electricity output while providing a cardio workout.

List of Materials

• 1 18-volt cordless drill
• 7 pipe clamps
• 1 old bike frame (including bike pedal assembly and bike freewheel)
• 1 2x2 wooden board
• 1 2x4 wooden plank (cut into three smaller pieces)
• ~25 Nails
• 2 U-clamps
• 1 USB adapter

List of Tools

• Solder
• Soldering Iron
• Circle saw
• Bike chain breaker
• Hacksaw
• Wire cutter
• Screwdriver
• Spanner
• Cordless Drill

Use a screwdriver to unscrew the screws that connect the drill’s external plastic casing. Once these screws are removed, extract the drill from its casing. Keep the screws for later use.

By hand, remove the top three layers of drill gears, careful to keep meshing gears organized and separate for reassembly. 

Remove the drill clutch (the piece shown in the image above.

Once the drill clutch is removed, reassemble the gears in their respective positions prior to disassembling them.

Re-twist the drill bit on top of the drill 

Using the soldering iron and solder, solder the drill’s wires on the positive and negative terminals on the back of the drill.

Once the solder has solidified, take the screws from step 1 and use the screwdriver to re-screw the plastic casing to the drill.

To test that the reassembly has been successful, spin the drill bit and ensure that there is no internal resistance.

Begin by popping the wheels off of the bike frame, if they are not already removed. This will leave you with a frame similar to the one shown above.

Using wire cutter and bike chain breaker, remove the wire and bike chain from the bike frame. This allows for the bike frame to be cut easier.

Using a screwdriver, remove the gears near the back wheel of the bike. Save these plated gears for later use.

Use the hacksaw to cut at the bike frame in the places shown in Figure 2.

Use a screwdriver to remove pedal caps (if applicable). The removal of pedal caps allows for more universal use of the bike since not all shoes will fit into the pedal caps.

Using 4 pipe clamps secure the bike frame down with the pedals up (See Figure 3).

Using the circle saw, cut the 2x4 plank into three equal pieces.

Using 3 pipe clamps attach the modified drill to a 2x4 plank.

Use 2 U-clamps and attach a 2x4 plank to the front of the bike frame (See Figure 4). The U-clamps need to be secured with a drill.

Then, attach the 2x4 wooden plank attached to the drill to the 2x4 plank attached to the bike frame. Make sure the gears on the drill and the bike are aligned.

You may use another 2x4 plank to stabilize the drill for increased durability; if you choose to reinforce the drill place the third 2x4 plank perpendicular to the other two, and use it to support the drill, placing it beneath the drill to act as a shelf. If you have the resources, use a saw to cut through the wood and fit the drill in the hole — this will ensure the drill is unmovable.

Once the drill is secure, drape the bike chain around both sets of gears. Using the bike chain cutter, cut the chain so that it fits around both sets of gears snugly, and close the chain.

Attach a usb adapter to the wires that extend from the drill. The product is ready for use.