Question about the SoR contest robot

[sotu]

My contest robot will be a radio controlled robot. The stearing plate will have 2 forward/still/backward switch controlling the each wheel. What i dont seem to understand is each switch has 3 power inputs underneeth them. From the batteryes there is 2 wires coming from each power leaders (the metal things leading power from the battery) and the motor i want to connect them to has 2 inputs to add power to.
So my question is: if the battery has 2 wires, the motor has 2 inputs but the switch only have 3? Thats 1 to little!

[Qubix]

The batteries, the switch and the motors all have a common ground, so the switch only needs 3 contacts. (i.e it only needs one Ground contact for both the motor and power ground connections)

Ground being the wire connected to the minus (-) terminal of you battery, usually the black wire.

Hope that helps


David

[sotu]

Im a little confused about what you just said, my english is good but still i got a lot to learn, so i was wondering if  you could the the picture underneeth, save it and draw lines on it (In paint or whatever) you could paint: red line= + power black line = - power maybe then i will understand it better.

[gamefreak]

if the battery has 2 wires, the motor has 2 inputs but the switch only have 3? Thats 1 to little

A battery has an input and an output(technically)

negative is output(or if you want to be conventional and not technical it is 0 volts/common(input))
positive is input(and if youi want to be conventional then it is output )

now the motor has an input and output, depending on which one you use as the input then the motor will spin in one direction, if you change the input then the motor will change direction

sorry i cant supply a picture that might work, but i have a headache and i have to teach kids tommorow and i only get two free Dr. Peppers

[sotu]

Ok think i got it, but i dont really seem to understand how this can help me to connect both the battery and the motor to the switch so when i push the swish forward the motor will spin one way and backward the motor will spin the other way. When the switch in in the middle it will be on the 0-point (The motor will stay still)
Here is the picture of the switch, as you can see there is 3 power leaders. As i have said before how do i wire it up??

[Admin]

if you want your motor to rotate in two directions and stop (3 states), you will need two on/off switches

[Qubix]

Yes sorry what I told you before would let you turn the motor on/off but not control direction (forward/reverse)

Perhaps you don't have the right switch for the job. The three positions that your switch goes to are probably on/off(when in centre)/on, not reverse/off/forward. If you have a multimeter, it should be simple to see what terminals are connected when you move the switch to different positions (use the continuity mode or resistance mode (very low resistance suggests two of the contacts are connected))

If you want to control a motor with switches you have two options

1) as Admin suggests uses two on/off switches
2) use a double throw,double pole switch (DTDP). If you have a copy of robots builders bonanza, there is a detailed description of how to wire on of these up.

I've *borrowed* a page from it, maybe this might help make things clearer

[ed1380]

or one of those double pole double throw switches.
you'll need to do something like this.

Edit: WTF? ^that post wasn't there?

[gamefreak]

i knew there was a reason i couldnt figure it out

[sotu]

if you want your motor to rotate in two directions and stop (3 states), you will need two on/off switches

I got 2 swtiches but do i then need both switched for one motor?

[sotu]

I've *borrowed* a page from it, maybe this might help make things clearer

On the image is the square with the three wholes in it the controller?
And if it is i only have 3 inputs on my switch!

[Qubix]

Edit: WTF? ^that post wasn't there?

Sorry Ed1380 I must have posted just a few seconds before you 

Sotu,
With the one switch you have you can turn a motor on and turn it off (but not make it go forwards AND backwards)
so you need either 2 of these on/off switch (which I think is what you have). One wired so when you press it, the result is that the motor goes forward, and another switch that makes the motor run backwards.

OR you can use

ONE DTDP switch. The DTDP switch is the rectangle with 6 more rectangles in it in the diagram ( the diagram shows two motors and switches but you can just look at either of them). It has 6 connections (not 3, so I'm guessing your switch can't do this ) and if it is wired up as shown, it would allow you have a switch that would control your motor, forward/off/reverse (which is what you seem to want your switch to do).

I think maybe your problem is there are quite a few different types of switches ( all with different names, no of contacts, internal workings), You can find a overview of them here

David

[sotu]

lol i know this is an old post now but just wanted to "warn" u guys that im not going for radio controller (wanna try something new) I have ordered servos, microcontrollers, USB assesories, everthing i need for an programeble robot...