Raspberry Pi controlled rail gun

[adamhaas98]

Hi guys, for the next term we have to make a project in physics of what ever we want. WHATEVER!

So i've decided to use my python code knowledge and love of computers to create a rail gun which will work by a line of electromagnets reversing their current as a ball bearing roles past a light gate. The plan for that design is to have two 12V DC car batteries setup so one will cause current to flow one way and one for current to flow the other. In order to make this work each battery needs a switch. So here's my question, how can i use my raspberry pi to activate a switch not be a switch? If i hook up the battery through the GPIO it will fry the board, so how to i use the raspberry pi to activate a switch. Thanks in advance

[trag1c]

You could possibly try using an SCR for your power gate. Its a diode that takes a signal input (this would come from the Pi) to complete the circuit.

 

Edit:

Heres a link https://en.wikipedia.org/wiki/Silicon-controlled_rectifier

[trag1c]

Hi guys, for the next term we have to make a project in physics of what ever we want. WHATEVER!

So i've decided to use my python code knowledge and love of computers to create a rail gun which will work by a line of electromagnets reversing their current as a ball bearing roles past a light gate. The plan for that design is to have two 12V DC car batteries setup so one will cause current to flow one way and one for current to flow the other. In order to make this work each battery needs a switch. So here's my question, how can i use my raspberry pi to activate a switch not be a switch? If i hook up the battery through the GPIO it will fry the board, so how to i use the raspberry pi to activate a switch. Thanks in advance

Also don't forget to follow your topic

[adamhaas98]

hahah yeah of course, the SCR seems like the concept I have in my head. If it's power is a 12v car battery what kind of voltage should the SCR be rated at?

[trag1c]

hahah yeah of course, the SCR seems like the concept I have in my head. If it's power is a 12v car battery what kind of voltage should the SCR be rated at?

I thinks a better question would be current since a lot of SCRs are built to handle way more voltage than that.

[trag1c]

I can't remember if I was reading the specification right since its been quite some time since I've dealt with any electronics but I think this should suffice and allow for bigger more dangerous things in the future.

http://www.digikey.com/product-detail/en/S6020L/S6020L-ND/2336

[adamhaas98]

thanks for that, the other method i have just discovered is using a relay switch, would that work well do you think?

[trag1c]

thanks for that, the other method i have just discovered is using a relay switch, would that work well do you think?

I don't think so since relays use magnetism to operate a switch which probably doesn't like strong magnetic from a rail gun.

[adamhaas98]

good point, thank you very much for your help. I do have another question though (sorry noob here). What can i use as a light gate to send information to the GPIO if a beam is broken, could i use an ldr? or do you have a nifty idea?