Van Door Motors for Drivetrain

Posted by Jason at 1/14/2001 7:47 PM EST

Engineer on team #221, MI Roboworks, from Michigan Tech and MI Roboworks.

I was just wondering what experience teams had using the Van door motors to drive their robot. I have heard that they are unreliable. Just wondering. Thanks

Posted by Michael Quayle at 1/14/2001 8:06 PM EST

Engineer on team #253, MRT, from Mills High School.

In Reply to: Van Door Motors for Drivetrain
Posted by Jason on 1/14/2001 7:47 PM EST:

Van door motors run slower in reverse than in forward, so they have to be mounted to eliminate this effect (at least in tank-style drive). However, they are very powerful, but I still would recommend drill motors for drive. Van door motors are usually more valuable in other robot systems, ie lift/arm/whatever.

Posted by Ken Leung at 1/14/2001 8:19 PM EST

Student on team #192, Gunn Robotics Team, from Henry M. Gunn Senior High School.

In Reply to: Re: Van Door Motors for Drivetrain
Posted by Michael Quayle on 1/14/2001 8:06 PM EST:

Van door motors are the third powerful motor within the motors provided, while drill motors are the most powerfull, and fisherprice second. Most teams use Van Door motors for high torque operation, while drill motors for drive trains.

There are couple of reasons: 1. One of the most important feature of Van door motor is that as the motors heats up, it will reduce power output, therefore the motor will slow down when you use it for a period of time. If you use it for drive train, you do not want to drive them for the for a long time. 2. The Van Door motors are pretty heavy, so when you want to build a light robot, you might not want to use them. 3. Van door motors do not like hard stops, while in the drill motor gear assembly you can take the stopping pins away so under hard stop, it will not destory the drill motors assembly while you are risking destorying the worm gear inside the Van door motor.

Posted by Ed Sparks at 1/14/2001 11:28 PM EST

Coach on team #34, The Rockets, from Bob Jones High / New Century High and DaimlerChrysler.

In Reply to: Van Door Motors for Drivetrain
Posted by Jason on 1/14/2001 7:47 PM EST:

The worm gear inside is made of plastic. If you are planning a direct drive from the shaft of this motor, I would think of something else …

Posted by Joe Ross at 1/15/2001 1:01 AM EST

Engineer on team #330, Beach Bot 2001, from Hope Chapel Academy and NASA/JPL and J&F Machine.

In Reply to: Van Door Motors for Drivetrain
Posted by Jason on 1/14/2001 7:47 PM EST:

In '99 we used a 4-wheel drive system that included
both the window motors and the van door motors. We connected the motors directly to the wheels, but there was quite a bit a machining that we did to make that system quite robust. Our robot was definitely one of the better teams at pushing that year and we never had any problems with either motors.

: I was just wondering what experience teams had using the Van door motors to drive their robot. I have heard that they are unreliable. Just wondering. Thanks

Posted by ChrisH at 1/15/2001 2:12 PM EST

Engineer on team #330, Beach 'Bots, from Hope Chapel Academy and NASA JPL, J & F Machine, Raetheon, et al.

In Reply to: We have used them for driving
Posted by Joe Ross on 1/15/2001 1:01 AM EST:

: In '99 we used a 4-wheel drive system that included
: both the window motors and the van door motors. We connected the motors directly to the wheels, but there was quite a bit a machining that we did to make that system quite robust. Our robot was definitely one of the better teams at pushing that year and we never had any problems with either motors.

It worked, but boy was it slow.

: : I was just wondering what experience teams had using the Van door motors to drive their robot. I have heard that they are unreliable. Just wondering. Thanks

Posted by Ken Leung at 1/16/2001 2:35 AM EST

Student on team #192, Gunn Robotics Team, from Henry M. Gunn Senior High School.

In Reply to: Re: We have used them for driving
Posted by ChrisH on 1/15/2001 2:12 PM EST:

That’s because Van Door motors are not powerful enough… you could’ve gear it to go fast, but it won’t be as strong as you want, or the other way around. The bottom line is, the power output from those motors are not as much as the drill motors, which mean the total torque/speed output will not be as much as the drill motors.

Posted by Nick at 1/15/2001 5:45 AM EST

Student on team #240, Mach V, from Jefferson Monroe High School and Visteon.

In Reply to: Van Door Motors for Drivetrain
Posted by Jason on 1/14/2001 7:47 PM EST:

From experience, our team knows about the Van
Door motors. The motors were designed to move a large van door. This task requires high torque applied in a short period of time in one direction. These motors are more than capable of doing that. The problem is if you use the motors for driving, make sure that both motors are running forward. We broke approx. 6-8 motors, but the original motor running forward most of the time is still on our 2000 robot. Perhaps instead of driving you should think of a task similar to their original design. Also think of what Barbie motors were designed for.

Posted by Matt Berube at 1/15/2001 7:41 AM EST

Engineer on team #49, Delphi Knights, from Buena Vista High School and Delphi Automotive.

In Reply to: Van Door Motors for Drivetrain
Posted by Jason on 1/14/2001 7:47 PM EST:

The drill motors w/ the drill gearbox attached can make almost 4 times as much power as the van door motors. This means that with the proper gear ratio a robot moved by the drill motors will have almost 4 times as much pushing power as a robot moved by the van door motors, (assuming the same speed)!

Assuming you are using 6 in wheels, I would suggest gearing the drill motors down by 2:1 if you use the low setting or ~7:1 if you use the high setting. You really should finish your chassis early and leave room to change the gear ratio if it doen’t seem right.

(Matt steps off the soapbox)

Matt B.
T49