Rotary encoders for 4wd bot

Hi :-)

I'm building my first bot with 4WD. I've read in a number of places that the use of encoders is strongly recommended. I have no experience with encoders. I will guess that they somehow help to keep all motors spinning at the same speed?

I've looked for arduino examples using encoders for 4wd bots but have been unsuccessful. Nick, I've seen a post where you were starting a 4wd bot but hadn't implemented the encoders. Have you progressed with your project? Can you point me to some explanation about the role of encoders with 4wd bots as well as code examples?

BTW, I'm using this controller: http://www.robotshop.com/dagu-4-channel-brushed-dc-motor-controller-2.html

Thanks in advance for any help you can provide,

Todd

What the encoder will do, in this situation, is tell you how fast the wheel is turning (and in what direction).

So you could translate, for example, the fact that you are sending PWM of 50% into an actual rate of turn (which might/would depend on the load, and slope, the obstacles, etc.).

I didn't proceed with them myself, although I posted a snippet showing how I originally decoded them.

The reason is, in my case I was driving "visually" ... that is, using the remote control. Also, if the wheel slipped for some reason, then it might be turning but the car wasn't necessarily moving.

So in this situation, I just didn't find the input from the encoders particularly useful.