I deleted my original thread because I realized a flaw in my thinking. (Don’t worry, no one replied. Unless… j/k)
As a result of some heated discussions in my team, I though I’d ask the collective FIRSTers.
Q: What motors do you plan to power your drivetrain? Is it a hybrid system with more than one type of motors?
Before you respond, consider the following:
Power
Current draw
Ease of machining
and anything else I skipped
If you also give me some sort of reasons behind your thinking, it would help me out very much. Who knows, may be I’ll even quote you at my next meeting! I’ll be sure to let you know if I use your quotes.
WE may be reconsidering the chalupas due to their heat problems…
If you don’t know what I am talking about, run them for about 15 minutes no load and then burn your hand checking to see if it is running warm.
Gear the chalupas and FP motors to the same free speed RPM. Mate the 2 motors to a gearbox (that you’ve custom designed for this purpose) and then drive the wheels with the gearbox.
Gear the chalupas and FP motors to the same free speed RPM. Use 1 motor to drive each wheel (4 wheel drive).
*Originally posted by thedillybar *
**There’s a couple of ways.
Gear the chalupas and FP motors to the same free speed RPM. Mate the 2 motors to a gearbox (that you’ve custom designed for this purpose) and then drive the wheels with the gearbox.
Gear the chalupas and FP motors to the same free speed RPM. Use 1 motor to drive each wheel (4 wheel drive). **
But why use two motors to drive a gearbox when one would be sufficient?
8 wheel drive train using 2 drill motors. thats alot of chain that we used and we use even more when we go to readjust / install a new motor since the motor never sits the same way twice
8 wheel drive?! i dont think so. true 8 wheel drive means you have one motor for each wheel not 2 spread across all 8. at least thats what ive been told
*Originally posted by Ricksta121 *
**8 wheel drive?! i dont think so. true 8 wheel drive means you have one motor for each wheel not 2 spread across all 8. at least thats what ive been told **
Not necessarily. Would you say a 4-wheel drive robot is not “true 4-wheel drive” without independent motors for each wheel? Whether a robot is 2, 4, 6, or 8 wheel drive depends not on the number of motors, but the number of powered wheels.
Our 'bots have often focused on speed rather then beefy drive trains. The extra pushing power of a 4 motor drive would have been nice, but didn’t really fit into our game plan. Two drills are the most bang for the buck (the buck being a number of things… weight, current, time). While being powerful, their transmission allows some flexibilty going into the match. With a third drill motor in the kit for a replacement, they make the perfect drive motor for most all FIRST 'bots. If you don’t use the drills on your drive, I’d be very surprised.
So while having the Atwoods or FP motors running with the drills would have been very nice (and were planned for '02), those motors are either more usefull elsewere or were to heavy.
Chances are 95 will stick with the drills. What can I say? We have this thing about really heavy (complicated) ball pick up devices. At least we’re good at something right?
We’ve used 2 drills in 2001. In 2002 we tried to use 2 drills and 2 chias but we had some gear stripping problems so we ditched the Chias. In 2003, we will definitely have 2 drills and 2 Chias.
*Originally posted by Wetzel *
**More than one drive train? As in a halftrack type device? Wheels and treads? Or something more exotic? Care to elaborate? **
Hey wetzel, alot of teams do this, they have a primary drive system, and then a secondary (powerful) one, Like CHAOS- 131, they have a tanks system and wheeled, they just engage at different times
We found the Drill and FP to well compliment each other (important on a swerve drivetrain) on our 4 independent drive modules, especially with the more powerful FP motors this year. We also kept the modules identical left to right so all the motors spun the same direction so that the drill timing was no longer an issue. We used the Chips for the boom that needed alot of power since it wasn’t counterbalanced, also they are heavy!! Definately the Drills on the drive they are a perfect fit for that.
*Originally posted by Matt Reiland *
**We also kept the modules identical left to right so all the motors spun the same direction so that the drill timing was no longer an issue. **
The drill motor has timing. Your kidding. We’ve been running it in reverse on one side this whole time. Can you elaborate a little more on this.
Drill motors are usually timed for better performance in the forward direction (for drill bits and inserting screws) so it has a little better performance in the forward direction. You could (depending on your robot design) see a slight curve in the driving of your robot because of this. Search the forum for Drill Motor timing, I know we have had discussions on it in the past and ways to correct it.
