Light Triggered Motor

I haven't seen a light switch for a motor that draws around an amp, so I thought that I would make one. The product works well - if I shine a laser on it, I can trigger it from across a room quite easily.

Also, I am thirteen years old. (Mandatory mention of age for robot's challenge)

Step 1: Materials

You will need:

Materials:

A motor. I took one out of a broken Nerf Barricade.

A TIP31 transistor. $0.20 http://www.taydaelectronics.com/tip31c-tip31-npn-transistor-3a-100v.html

A 2N3906 transistor or similar PNP transistor. $0.02 http://www.taydaelectronics.com/2n3906-general-propose-pnp-transistor.html

A battery holder. I used one that held 3 AA's. $0.14 http://www.taydaelectronics.com/aa-battery-holder-5.html

A SFH 314 phototransistor. $0.58 http://www.mouser.com/ProductDetail/OSRAM-Opto-Semiconductors/SFH-314/?qs=K5ta8V%252bWhtbR6gV8hNfmATd6ftDkb0eH0AduyQe8MSk%3d

Perf Board. I used one I had laying around, but you should use Radioshack's miniboard, which costs around $2.19. http://www.radioshack.com/product/index.jsp?productId=2104052

A laser pointer is recommended to activate the light switch.

The total cost came to around $5, with shipping.

Tools:

Soldering Iron
Screw driver
Wire strippers
Optional: Breadboard

Must be able to solder and read schematics

Comments

[dsandds2003]

Can you use higher voltages to drive a larger motor?

[seraine]

By this, do you mean using this with motors that are more than 4.5 volts? If so, I believe that the motor you use can be up to 40 volts. I base this on the fact that the maximum collector emitter voltage on the TIP31 datasheet is 40.