Step 10: Adding the Electronics

The electronics for the mobile bar are fairly simple using off-the-shelf items. The entire robot runs off a 12 volt, 35 amp-hour SLA battery. The radio controller/receiver is a six channel Futaba model tuned for ground frequency use. This was purchased from The Robot MarketPlace.

A pair of Victor 883 Speed Controllers is used to control the drive motors on BaR2D2 and are set up for "tank-style" steering. Note - for ease of driving, we set the transmitter up to use one stick to control the drive (mixing function). Follow the instructions included with the speed controllers for installation and setup. These were mounted on a piece of Sintra.

I reused the wiring harnesses and plugs from the wheelchair to provide wiring from the battery, to a main switch and to the motors. This allows you to easily unplug everything for transport. The switches and wire were purchased at Radio Shack.

At this point, limit switches were on the beer turntable. They are wired in conjunction with the beer elevator and beer loading door so that: A) Anytime the elevator is up, the turntable can't spin, B) When the elevator goes back down, the turntable is allowed to rotate until the next beer hits a limit switch, C) The turntable and elevator can't spin with the loading door open, D) A manual three-way switch allows for loading/off/dispensing of the beers. See diagram below. Zip-ties were used to secure the wiring.

Dear Author:
I still do not understand your method of wiring between the radio controller/receiver and the speed controllers.  Can you send me the sketches that you made for the wiring?  Do I have to use the servo - and does it take signals from the radio controller?  Thank you. 
djsteils6 years ago
elevator too... The turntable is under plexi glass which is bar level and i want the elevator to bring it up to bar level.
jamiep (author)  djsteils6 years ago
for the limit switches to control the spin of the table and the elevator, you need to make sure these things happen: limit switch that is actuated by the elevator hitting its full down position. This allows the spin motor to energize. limit switch that is actuated by the "teeth" of the spin table. This will interupt power to the elevator unless the table is in a position for the elevator to go up without hitting a tooth. limit switch (reed switch) that is actuated by the beer bottle. This kills power to the spin table as soon as a beer hits it. when the beer goes up and the elevator goes back down, the next beer advances. A 3 way switch for loading, unloading, and off position. This reverses the table for loading, and then allows for forward motion of the table. In your application, another 3 way switch would probably be used to actuate the beers instead of a remote control. jamie
djsteils6 years ago
Can you be specific with the wiring? I am building a similar beer turntable for my dorm room. How do the limit switches work?
jamiep (author)  djsteils6 years ago
Are you building just the turn table and need to stop the beers, or are you building an elevator too? jamie