There have been a few post on the capacity of the motors and servos and such. I’ve got this idea going to have to see how this is going to work but i want to place the idea on everyone. now this is a bit advanced in model making, pcb etching and circuits, and mechanical thought processing.

The Vex microcontroller can only handle 8 motor/servo ports. The transmitter can handle up to 6 channels with out programming. There is a way to get your transmitter to go up higher by using channel 5 and 6 to trigger a script in the controller but thats later on i don’t program i have difficulty understanding that language. So i leave it up to my disabled friend he is a genous at programming so it works out i do the hard ware he does software.

Anyway we were sitting up at waffell house the other night like we do every night talking abou the easy febuary challenge and drawing out ideas and i told him how i would like to be able to put a disc on my bot that had my power cords with it woven in. and that got him to thinking about what kind of disc i would use. and after explaining it he was like wow and he drew something that could change the electrical path between two devices with a slight rotation. I was like thats a good idea. So i did soem brain storming and thought well this could be very hard to do with the 3 wire configuration.

So after some thought i said hey this is done in train yards of old witht the steam locomotives being put into the garages. example can be found on the show thomas the train. And I remember working on an electromagnetic crane that had a contact disc that the power transfered to. and then the idea was born.

You take one channel and reserve it to operating the disk then that disk can rotate 360 degrees and trigger as many motors or servos that you have room to place. I’m starting out having it controll 4 independent systems. now you will need the optical shaft encoder so when you press one of the channel buttons it starts a mini program to rotat the disk a certain amout to energize the next motor/servo.

This is a layout of the copper disk


the greyed in areas are the proposed copper traces from my etching. so that will be located on the top of the stack.

then there will be 3 layers of a disk that is made of nylon and will have a hole cut out for wire pathing and external access they will be cut like this


followed by a blank disk that is solid to kepe things out of the insides.

the wires will be feed to the outside rim and there is three disks because each disk will be one of the wires. to make it all nice and uniform basically.

A few things i will need to work on will be finding some old electric race cars the ones that have the trigger controllers. some of us older folk know what they are. I will need the spring loaded contacts from them. so that leave creating something to deliver the signal to the copper trace board and something for the output to make contact with. But in theory I am only limited by the size of my disk on how many different paths i would be able to create. like i said before i’m wanting one channel to be able to use 4 or 5 motors one at a time of corse. and i have one of the disks made here is a pic.


Oh didn’t explain how it will work i don’t think if so my appoligies on repeating too many interruptions while typing this.

this will be triggered by channel on my transmitter. pressing the button left will make it rotate a specified distance counter clockwise and pressing the button on the right will make it turn clock wise a specified distance. one problem i know i will have to defeat will be is calibration on power up. only way i can figure out is maybe use the line follower sensor and have it start up and search for the end and start the counting process there.

Let me know any ideas you may have on this subject. I only hope that it doesn’t turn out to be like the grand idea i had about the crystals hehehe.

Something like this is useful for “BEST Robotics” where there are only 4 transmitter channels, but 7 motors/servos available, but no Microcontroller available. I dont see the point in doing it with Vex, since there is a microcontroller and 8 motor ports available already, unless you needed more than 8 motors independently.

Your plan requires programming already, so why not do all the work
with programming, rather than half and half.

well my last major bot had a grand total 10 motors and servos on it and i was using 2 transmitters to operate it but what i am looking to do will be able to controll more than 8 in any given scenero. i have the 3 disks completed now just need to start on the copper portion of this so we will see how well it goes.