Hello! I am buiding a robot with 4 wheels. I have two motors, and each motor will be linked with a back wheel. The problem is I don't know how to develop a directin mechanism. At first I thought to control it by modifying the turation of each motor, But this wouldn't work because of the friction for the front wheels. Please can you show me a mechanism? Thank you!
There are several choices:
Use a single front caster wheel or maybe mount the front wheels on an axel that can turn to act as a caster.
Steer by turning the front axel with a servo.
Put tracks around the front and back wheels and use 'tank' (differential speed) to steer.
Use omni-wheels (wheels that can roll sideways) in the front.
Hi nimeni_altci, Never built a 4 wheel bot because of the very problems you're having now. I think if you chose 4 wheels then they all need driving, but as JW suggest perhaps there are other ways of doing it!!
I find two wheels set about midway along the chassis and a rear caster, do the trick most of the time, a front caster/wheel just gets in the way, and often will not go over/up carpet edges and the like. I think motors are better at pulling then pushing? unless it's a tracked bot.
You can see some of my early buggy-bots here (Under Electronics): www.melsaunders.co.uk I am working on 2 new ones now, a little more advanced and a little harder work using new devices, etc and with the coding too.