|
|
|
![]() |
|
|||||||
|
||||||||
|
|
Thread Tools | Rate Thread | Display Modes |
|
#28
|
|||
|
|||
|
Nearly off the shelf...
Posted by Joe Johnson.
Engineer on team #47, Chief Delphi, from Pontiac Central High School and Delphi Automotive Systems. Posted on 5/24/99 6:55 PM MST In Reply to: Re: Maybe a Partial Solution to the Learning Curve posted by Rick Berube on 5/23/99 10:16 AM MST: To my mind, your comments are exactly why FIRST should go with a nearly off the shelf system. 3 years back, I tried to roll my own robot controller using a 68332 based New Micros Inc single board computer. It almost killed me... The machine had TONS of CPU speed, what I needed was a standard library of useful functions. Before I gave up, I had the onboard TPU (Time Processing Unit) performing the PWM function in an automonous mode, much like the Serial Servo Controller (SSC) does now only much quicker to access (a single write to memory rather than a serial stream to the SSC). In the future, such partial solutions can be made available to all. I think that it is possible for FIRST to use an off the shelf or nearly off the shelf single board CPU. But, there will be problems to deal with: 1) Control of high current loads This can be dealt with in a number of ways already discussed. 2) Watch dog curcuitry to cut off power in case of a lost radio signal or the end of a match It is pretty standard to have watchdog curcuitry onboard single board computers, if first used a radio with the checksum and security stuff incorporated inside its internal CPU then it could also provide the watchdog signal(s) to the watchdog curcuit. I suppose that a bit of care would have to be taken to see to it that clever EE-types don't disable the watchdog (you have to watch those highly paid sneaky electrical folks ;-) but I think that this would not be too much of a problem. If it were we would have already seen some cheating because the current system is far from invulnerable (A snip here a cut trace there and your robot could continue to run regardless of what FIRST did to the TX signal). It is no more or less an honor system than whether or not a team's BOM actually matched the robot. 3) High learning curve. For my money, the best way to beat this is for FIRST to decide to use an off the shelf controller NOW or ASAP and then tell the world where to get it. I would like nothing more than to teach a CPU class or a C class or a digital curcuitry class next fall to the students on my team. Winning animations are already being designed and built for next year. Why can't the winning control program already begin? Also, I think that if we choose an off the shelf system, then we can all go to existing user groups for help. There are a lot of very clever people online, many of them give advice and consulting free if asked. This could be no different. In addition to this, an off the shelf controller has existing documentation and support for its product. Once again, this puts us ahead of the game. As to the difficulties of C, I agree, that C is a language for consenting adults, but with enough examples and a fall back default code, we can all get through this. After all, we don't tell teams that heat treatment of steel is tricky business best left to folks who know what they are doing. No, we allow heat treatment or not as teams see fit. This C thing could be just like that. Many teams may choose to use the default code with only minor changes. Others may be implementing Kalman filters and State Space control schemes -- let us all seek our own depth. I think that the GNU model mentioned in a prior message is not far from how the FIRST online community would support a new commercially available computer. If we (ChiefDelphi.com) put up a forum on code issues, don't you think that we could all climb that learning curve faster than you can say, 'Realtime Multitasking C'? 4) Others I have not thought of... I think that we can do this. I think that we SHOULD do this. Now is the time to do this. Who will join me in finding an appropriate commercial solution? I think that if we find a good solution we can sell it to Eric and the gang back in NH. Joe J. |
| Thread Tools | |
| Display Modes | Rate This Thread |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| serious problem found - robot controller resets when jarred! | KenWittlief | Electrical | 23 | 19-03-2003 13:30 |
| Visibility of Robot Controller and Reset Button | Tracy | Rules/Strategy | 1 | 17-02-2003 07:36 |
| How do you connect the speed controller fans? | Iain | Electrical | 7 | 31-01-2003 07:05 |
| Problems with rookie ideas?!? | Tton | General Forum | 7 | 08-01-2003 22:10 |
| Robot Types (post your ideas here) | Rick | Rules/Strategy | 30 | 10-02-2002 12:09 |