Line follower project
May 17, 2010
Hi guys, I'm working to build a linefollower robot to compete in both linefollowing and maze solving contests, but I've a few questions and problems I hope you could help me resolve.
Well, the first problem are the motors. At the beginning I was using two 3v - 6v motors and this worked fine, but I had to duplicate the H-Bridge chip on my Picaxe 28X1 Started Pack due to the high amperage they required.
Now I need a more accurate speed control, so what would you do? Could I use two brushless motors with two ESC controllers on my board instead of PWM? I think this would be better because it would only take two output pins instead of the four required with the L293D. If this is better, what do I have to do to make them work? I've understood that they use a regular servo signal to work...
And the last question about the motors... Do you recommend me any particular brushless motor? To make an idea of the weight and size of my robot, it's like a slot truck but a little heavier because of the batteries and other robotic stuff.
The second problem is that I may need another kind of batteries of a higher voltage to run the motors, because now I'm using the 3x4,5v baterry pack that came with the starter pack, so my question is: If I replace them for a 11.1v Li-Po battery, would you use one voltage (5v) to run the PIC, another one (6v) to run the servos and the 11,1v to run the motors (powered through the ESC) or only one to run both PIC and servos (5v) and the 11,1v to run the motors? If I do the last thing, how can I take that 5v out of 11.1v?
LINE FOLLOWER MODULE:
Well, that is my last problem. At the begining I wanted to build a linefollower module with 6 CNY70, but recently I found an 8 reflectance sensor array on Pololu that could be better than that and there are two different versions, the analog one and the digital one. I want to use the digital one, but I don't know how because the Picaxe board only has 4 analog inputs, so is there any solution or I will have to buy the digital one? If you know any other kind of sensors that would be better just tell me...
I thinks that's all. Thanks for your help!!