[manderson5192]

Having just completed this season's robot, I have developed a high level of interest in making a custom circuit board coprocessor to process sensor inputs from a robot so that, via a simple RS-232, TTL, or whatever connection (maybe even USB or RS-485), a master processor could poll this coprocessor and get back the output of multiple PID loops or navigation software. I really have no end goal except that the coprocessor would process sensor inputs from a CMUcam, encoders, potentiometers, or just about any other sensor and provide an output to a master processor. Now, I have read up on the Adambots solution to this idea, which was to use a gumstix computer. I have also considered using a mini-ITX motherboard. The only problems I see with these solutions are 1) I have no interest in learning linux just for a coprocessor 2) I'm not convinced an RTOS (realtime operating system) is really necessary 3) Even with an ITX motherboard or a gumstix computer I would need another solution to get sensor inputs.

All that said, I have begun to look at AVR microprocessors. Gumstix sells a $49 robostix board which sports an AVR ATmega128 chip and enough IO ports to handle all the sensors I am thinking of using.

I have just a few questions:
-Is there a better approach to this idea? Is an AVR solution better than PIC?
-Is it worth it to instead build the entire custom circuit rather than buy something like the robostix?

Thanks!
-Matt