Motor with encoder
Hello everyone. My college has some project organised, to introduce mobile robotics to highschools in my country, and they asked me to design a robot which would be used for that. And it needs geared motors with encoders, and since the only thing I ever used was servos, I need help choosing them.
Robots would be around 1-2kg, and it would be good to be able to carry atleast 1 more kg. Batteries would be 4 AA, either rechargable (4.8V) or normal (6V), so the motors should work for both. They should be as cheap as possible, because if we can lower the cost of one robot we can get more robots! And the shop would have to have around 100 of them.
So I need your recomendations for motors and place to buy them! Thank you very much in advance everyone :)
@ Sat, 2012-01-28 16:05
You might consider Rover 5
@ Sat, 2012-01-28 02:55
Well, I have to say that
Well, I have to say that motors with built in encoders don't come cheap for the weight you're planning. To move 3kg on a level surface, the motor needs to put out half that weight (you will have 2 motors) at the surface of the wheel that touches the ground (the wheel's radius). Say that the wheels have 10cm diameter, at 5cm radius the motor needs to put out 1.5kg, that means at 1cm, it needs to put out 7.5kg force. This is the minimum, always is a good idea to have stronger motors. So, motors that have 8-10kg-cm torque with built in encoders you can find at Pololu: http://www.pololu.com/catalog/category/116 but will cost you $40 a piece.
If you can lower the weight limit, here is a motor that has built in encoders and about 1.2kg-cm torque. http://www.goldmine-elec-products.com/prodinfo.asp?number=G16279 Watch out for it, from time to time they have it on sale for $7.95. Here is a good read about it: http://www.robotroom.com/FaulhaberGearmotor.html