Using an Arduino as a robot controller (2010 and beyond?)

[Leav]

Where are the major differences that create the "thousands of dollars" difference between the Arduino and it's IFI (distant, distant) cousin?

lots more inputs and outputs? faster CPU?

(not really asking about the NI controller here cause I understand that's a whole different ball game - ARM CPU, RAM and whatnot...)

[Dave Flowerday]

Originally Posted by Leav

Where are the major differences that create the "thousands of dollars" difference between the Arduino and it's IFI (distant, distant) cousin?

A few things:
- The processor in the IFI controller is more powerful than the ATmega used on Arduinos, and slightly more expensive (~$20 versus ~$5 for the ATmega168 common on Arduinos).

- The IFI RC actually contains 2 microprocessors, one that is dedicated to generating PWMs, radio communication, and handling things like disabling the robot, while the other is user-programmable.

- The circuitry on the IFI RC is more complex than an Arduino. The RC is designed with things like ESD protection on the inputs, much better power regulation, etc. This stuff is what makes the RC much more robust (and resistant to electrical "oopses") than an Arduino.

- There are a bunch of different connectors on the RC. Connectors are expensive, adding to the BOM and assembly costs.

- The RC comes in a nice injection-molded case for protection.

- (Most importantly IMHO) The RC has a lot of custom software in it that someone had to write (to talk to the OI, disable robots safely, etc). Also, it had to be designed, heavily tested, and supported (taking customer calls and sending IFI reps to every event for the last 8 years). This creates a large up-front cost (to pay engineers to do this design and development) that has to be amortized across the number of RCs sold during its lifespan.

You can make the same comparisons between the new CRio and other PowerPC-based boards. The CRio is easily 10x more expensive than other PowerPC-based devices on the market, and that is probably in large part due to the level of testing, robustness, and low volume nature of the product.

Basically, the cost of these components is the price we pay for getting the kinds of features and support we've come to expect.

[Leav]

So come 2010, assuming we still use about the same amount of PWM outputs and relays, and using some sort of RF module it should be possible to do rudimentary robot control, right?

Sure, there wont any OCR (or coffee making) like the cRio can do, but a basic joysticks+basic sensors+motor outputs should be possible...

I'm generally pleased about this revelation, I'm not so uneasy about reusing the cRio anymore..... it actually makes more sense in my opinion....

-Leav

[keen101]

I'd really like to do this. The current arduino's are a little small in terms of memory and i/o ports. But, it would be fairly easy to port the arduino bootloader to a bigger AVR processor, and pretty easy to design a ifi "clone" board of sorts. I am working on a design like this in eagle cad, but it is kind of on hold right now. email me if you want the eagle files.

the difference between the IFI systems and the compac rio is betty big. one is capable of running embedded linux.

But, i still think a cheap Robotics based Freeduino should be attempted. It could be used to drive simple robots around from previous competitions. But i think it would be possible to make a freeduino controller that could be just as good as the IFI controllers.

keen101 [at] gmail [dot] com

[EricVanWyk]

Originally Posted by keen101

I'd really like to do this. The current arduino's are a little small in terms of memory and i/o ports. But, it would be fairly easy to port the arduino bootloader to a bigger AVR processor, and pretty easy to design a ifi "clone" board of sorts. I am working on a design like this in eagle cad, but it is kind of on hold right now. email me if you want the eagle files.

I'd strongly recommend using Altium instead of Eagle. Altium is the best EE cad package I've used by far (and I've used quite a few of them) AND is in the kit of parts.

If you do need help with a design captured in Altium, just ask. I'd be happy to help convert you.

[AndrewN]

Umm, Altium might be in the kit but I cannot get a PCB manufactured from the design and I don't have $12K to spend to get the license. I'll withdraw the comment if you can tell me how to do this for a reasonable cost.

[EricVanWyk]

Originally Posted by AndrewN

Umm, Altium might be in the kit but I cannot get a PCB manufactured from the design and I don't have $12K to spend to get the license. I'll withdraw the comment if you can tell me how to do this for a reasonable cost.

Andrew -

Your post confused me, so I chased it down with FIRST's Altium Rep. She told me that the Altium you receive in the Kit of Parts is the full blown Altium Unified Licence with a 12 month timer. This can export your board to many standard formats, including Gerbers. Gerbers are accepted by all of the board houses I've worked with, although I hear that some of the super-low-end houses only accept their own proprietary format.

If you need any help with the export/fab process, feel free to PM me or post here. Alternatively, we can set you up with the Altium Forum - the community there is on par with Chief Delphi for helpfulness (dare I say better? ).

- Eric

[AndrewN]

Thanks Eric, I'll check Altium out again when we get our KOP in Jan.

[keen101]

I found this today. Pretty useful actually.

http://www.curiousinventor.com/kits/roboduino

however, it still has limitations, and and i am still set on attempting on creating a larger version similar to this with a more powerful AVR processor. Maybe a sanguino based version. I don't know if it's practical, but I'm still going to keep working on it, even if it only turn out to be for my benefit.

[chmp09]

The only reason why the IFI board was so expensive is because it was made specifically for FIRST. If it were used by a wide variety of people and produced on a larger scale, then it probably would have been a fraction of the price.

[IKE]

Originally Posted by Dave Flowerday

A few things:

- (Most importantly IMHO) The RC has a lot of custom software in it that someone had to write (to talk to the OI, disable robots safely, etc). Also, it had to be designed, heavily tested, and supported (taking customer calls and sending IFI reps to every event for the last 8 years). This creates a large up-front cost (to pay engineers to do this design and development) that has to be amortized across the number of RCs sold during its lifespan.

You can make the same comparisons between the new CRio and other PowerPC-based boards. The CRio is easily 10x more expensive than other PowerPC-based devices on the market, and that is probably in large part due to the level of testing, robustness, and low volume nature of the product.

Basically, the cost of these components is the price we pay for getting the kinds of features and support we've come to expect.

To elaborate a little further:

If you read Wired Magazine (two issues ago) they interviewed the guys that originally designed and made the Arduino (a good article). They posted their designs up for free and allowed the community to help them design and trouble shoot all of their problems. They basically put 0 n the price for the ER&D for these. To take this into consideration, say 1 very skilled EE did all of the design for the IFI controller in 1 year. If you paid such person $50K for that year, and you sold 10,000 controllers a year, it would take 5 years to pay for his 1 year of work if $1,000 per controller was earmarked for ER&D. This is the one reason why anything well designed in low volume is very expensive.

Doing a free ER&D version and allowing the community to troubleshoot your problems works very well for hobbyists (they are forgiving of errors and bugs), but would be a huge headache for non-expert teams.