New Robot Control System!

[BrianBSL]

Originally Posted by Salik Syed

I don't see what the big need for an "embedded device" is ... why limit our selves to using chips that were designed for controlling microwaves? The way I see it the only thing these types of chips should be doing is communicating low-level data -- PWM values, sensor inputs etc.

It makes sense to use these chips if you have a very small robot or a flying robot that cannot wirelessly communicate to a master processor, and needs a computer which is light weight and low on power consumption. The robots we build for FIRST do not fall into this category. We can slap a laptop onto a FIRST bot very easily ...2-3 lbs extra is marginal, battery consumption is also very low.
It would be nice to be able to do more object oriented programming instead of having to deal with simple low level constructs. It would open a whole new world of possibilities.

I know others have covered this, but I absolutely cringe at the prospect of a general purpose PC as the primary robot controller.

By embedded controllers, no one means 8051's to control microwaves, we're talking about Xscales and such that run your pocket pc phones and DSP's that run your TV's and digital cable boxes. We're talking about full size ARM/DSP/etc 32-bit processors which are designed for embedded systems and not general purpose computing, which is exactly what we need. We don't need video, we don't need IDE, chances are we don't even need a PCI bus, which on a x86 system require external northbridge and southbridge controllers which are just excess. In addition, the price on them is far more than necessary for our platform, and they typically have a much shorter lifecycle than embedded microprocessors. What happens 4 years after the launch when Intel has EOL'd or obsoleted the chip that was chosen? We're stuck modifying the system in some way to support whatever we can get. Not to mention the fact that they often lack GPIO and extensive external interrupts, as well as other things that are 100% necessary for our application. Nor do we want to have to worry about some fancy DC-DC system to provide 4 different voltages to stuff.

And, I've never found that we have 2-3lbs to spare to put a full size x86 system on our robots. In addition - embedded doesn't have to mean small, battery powered, low current consuming devices. I have some cards at work with what would be considered "embedded" processors on them that will far outperform an equal cost x86 system.

Just because it is what you are familiar with doesn't mean its the right tool for the job - luckily, hopefully, FIRST will have a team (IFI or someone else, who knows at this point) that can handle it, and we will adopt to whatever they come up with.

And as far as cost - just because Dells sells laptops for $500 (which is cheaper than the current IFI robot controller) doesn't mean thats what an integrated system costs. The two microprocessors on the RC cost no more than $40 total - when bought as single units (and get deeply discounted by bulk purchase, as well as the fact that Microchip might be kicking something in). I'd estimate the whole board has $100 of parts to it. There's some serious markup here, as there is some serious support and R&D that goes into it.

P.S. - I think my cell phone runs code a bit higher up than C... and I know it runs Java.

I'm not sure what you mean by that - I'm pretty sure that the OS in the phone wasn't coded in Java, unless it runs java byte code natively.