Re: Additional field coils around motors
 

Dave is the closest thus far, the motors already have a magnetic structure designed in. Trying to add to that will likely not result in an increase in performance. However, under another rule, solenoids are not allowed. See also the robot allowed parts flowchart.

Re: Additional field coils around motors
 

True. But it's not the result, but more the intent that bothers me.

Re: Additional field coils around motors
 

??

Re: Additional field coils around motors
 

I believe that Jack is concerned about the collective state of mind of a team that encourages them to bend the rule in this manner.

I'm not sure that it's unhealthy to try to push the limits, to exploit loopholes and to generally make life a mess for the inspectors and rule-makers. It's occasionally a little frustrating for those officials, but ultimately, it's mostly harmless. If the inspector or rule-maker says "no", it's final, no matter how much effort you put into it; by bending the rules, you take the risk you will find yourself in that situation. (Now, I should point out that decisions to live on the cutting edge should be undertaken with the consent of the team as a whole. If it's a small group within the team that risks the team's success on a dubiously legal enterprise, which is eventually rejected at a competition, all hell might rightly break loose in that team's pit; just leave the inspectors out of it.)

Re: Additional field coils around motors
 

I think that is important to note that winning teams have won without bending the rules. GP allows you to go ask, investigate and take pictures. Learn from others when you have the chance.

Re: Additional field coils around motors
 

[quote=Tristan Lall]I'm not sure that it's unhealthy to try to push the limits, to exploit loopholes and to generally make life a mess for the inspectors and rule-makers.QUOTE]

Agreed. Limits are imposed by both man and nature. Understanding those limits and attempting to push past them is the basis of creativity. Railing against them is unproductive, which is to say lets have fun with the ideas.

Re: Additional field coils around motors
 

accepting the limits of nature? Im not too sure about this

many times it wasnt nature, it was our understanding that was flawed.

Several years ago 2.8k modems were the best you could get, because Nyquist said that is the fastest that data can be transmitted on a phoneline with a 3,000 Hz bandwidth

but now we have 56k modems, on those phonelines with the same 3kHz bandwidth

nature folded on that one and gave in. Sometimes it pays to keep railing :^)

also, sometimes when you sit and ponder ways to cheat, you come up with a good idea that is not cheating - unrestricted brainstorming!

Re: Additional field coils around motors
 

[quote=KenWittlief]accepting the limits of nature? Im not too sure about this many times it wasnt nature, it was our understanding that was flawed.
QUOTE]

You misunderstand, what I said was complaining about the rule is unproductive. Railing: "to revile or scold in harsh, insolent , or abusive language" (from Merriam-Webster). What I was suggesting is that "out of the box" thinking is valued, and would like to encourage it.

Re: Additional field coils around motors
 

even if ignoring legality and spirit, i htink cooling the motor would be a much better way to 'boost' performance. a simple way we used and was effective (for our OCCRA robot) 2 years ago was to have tubes connecting the exhaust ports from the pneumatic cylinders to blow into the motor endbell. (we used our cylinders almost continuously that year and fans are not legal in occra or we didnt have any available... dont remmebr which) but as a concept it worked well. but then again from last year we learned how to make a more efficient drivetrain with much less friction and got a more 'easy on the controls' driver and havent burned a single motor since. :D

Re: Additional field coils around motors
 

This thread points out the Tim Allen mentality as applied to robotics. More power. However, with with the reality of the ever increasing cost of energy, the wise conservation and application of power makes more sense. A KOP trans with dual cims has a considerable amount of power. The use of this power in design and strategy will probably yield better results than trying to add more power.

Re: Additional field coils around motors
 

I'm not really interested in trying this, just wondeing how other people saw it, glad I could stir up more than one point of view. Personally, with as common as 4 and 6 motor drive trains are now, I thing that transmission development is probably the next big area that can be developed, even more so than it is.

last year there was talk of robots killing batteries in a single match... Something like this wouldnt help matters much, but its fun to think about.

Re: Additional field coils around motors
 

well, no... actually motors with super magnets would be lighter and smaller for the same amount of torque or HP output

and a motor with a smaller armature will have less internal (rotational) inertia, which means it will accelerate faster and have a better response curve, allowing it to be used with tighter PID control loops.

Using a better motor gives you several benefits => advantages. Only problem so far is that FIRST understands this completely, and they have kept motor modification and substition off the table of options.

But that doesnt mean we cant talk about it :^)

BTW, controlling a motors field strength, buy using field coils instead of permanant magnets is a better way to control the motors speed and torque. With a strong field the motor will run slow and have lots of torque. With a weak field the motor will run faster, but have less torque.

Re: Additional field coils around motors
 

This has been an issue since the beginning of time. Some teams are proud of it and some teams recognize the liability. You won't find many one match robots in finals.

Re: Additional field coils around motors
 

I second what Al said. With the total current limits imposed on the robot (by the rules and the main breaker) and with the 12V battery a bot can pull approx 2HP from the battery continuously

that is a LOT of power! A healthy 18 yr old male can put out about 1/3 HP continuously for 2 minutes, therefore the power available to your bot is the same as having six young men exherting themselves to their full capacity.

If your bot is expending that much power for the entire 2 minute match then something is seriously wrong with the design of the machine. Most of that energy would have to be fighting against itself, not other robots. For example: tank steering with 6 rubber tires or tank treads, that takes full power just to turn, compaired to a bot with 6 omniwheels, that can spin around as easily as it can move forwards or backwards.