Motor that can be dropped off a building.

[dtengineering]

Originally Posted by NextPerception

...A full body spinner has a spinning outside shell with sharp blades on it with a stationary inner chassis that has the drivetrain and spin motors as well as all the other robot essentials on it.

...The worst thing that could happen to me in battle is my center shaft bending or the plates that support the center shaft being tweaked so the center shaft iss no longer on the vertical axis...

I'm assuming this means that you mount the spinning outer shell of the robot directly on to the output shaft of the gearbox? (A photo or CAD image would be helpful) If so, I can see why the gearbox would be prone to failure.

Might I suggest building a custom shaft to support the spinning part of the robot ( you could make it out of 1" diameter solid titanium if you wanted) and weld that in to your frame, then use a pulley from the gearbox output shaft to spin the outer shell? That way (espeically if you build a bit of slip at high impact in to the belt) your gearbox output shaft will not be supporting the load... or impact... faced by the spinning outer shell.

Jason

[colin340]

Originally Posted by ebarker

just to be really clear.......

I'd bet any old transmission can survive the drop....

It is the 'undropping' process that is the real problem.

yes the drop aint the problem it's that whole slowing down thing

[NextPerception]

Originally Posted by artdutra04

Seven stories is a bit extreme, and way more than anything you'd ever see in combat robotics. Negating air resistance, any object through off a seven story building will reach a speed of about 20 meters per second (or about 45 miles per hour) when it hits the ground.

If you want to do some simple physics equations, you can calculate the exact final speed at impact from a seven story height, as well as how much kinetic energy the robot would have when it hits the ground. Compare this to the kinetic energy that the spinner would have at full speed, and you may find that a one or two story drop would probably* be a lot more realistic (and easier to design for).

* Just a swag. Do the math for an exact answer. There is great truth and wisdom to be held in the numbers.

I don't have the luxury of being able to design for anything less. My robots's spinning weapon strikes the opponent at 258mph maximum. that is more than my robots terminal velocity. This means I could drop the thing from 12 strories and it still wouldn't make a bit of difference.

Originally Posted by FourPenguins

Have you looked at cordless drills? I have no personal experience, but a higher quality cordless drill is designed to take a beating. (Consider their normal operating environment on a construction site.)

I Have looked quite extensivley into them and they just wont fit.

Originally Posted by dtengineering

I'm assuming this means that you mount the spinning outer shell of the robot directly on to the output shaft of the gearbox? (A photo or CAD image would be helpful) If so, I can see why the gearbox would be prone to failure.

Might I suggest building a custom shaft to support the spinning part of the robot ( you could make it out of 1" diameter solid titanium if you wanted) and weld that in to your frame, then use a pulley from the gearbox output shaft to spin the outer shell? That way (espeically if you build a bit of slip at high impact in to the belt) your gearbox output shaft will not be supporting the load... or impact... faced by the spinning outer shell.

Jason

I don't support my spinning shaft off of the gearbox. I already do something similar to what you describe. However, the motors for the spinning part are not the ones being questioned.

As far as a CAD image is concerned. here yah go. What that is am image of is the bottom of the robot with no bottom plate or spinning weapon visible.

Originally Posted by colin340

yes the drop aint the problem it's that whole slowing down thing

Yes indead, so are you suggesting installing an airbrake on the robot?

[vivek16]

have you actually tested the motors themselves in actual fights yet?

I think your problem may just be the gearbox being too weak. I'm not sure though.

You could always make your own gearbox .

EDIT: This whole concern is about your gearbox shaft getting damaged right? Have you considered using a racheting mechanism so that when it rapidly decelerates, it won't harm the gearbox shaft?

[NextPerception]

yeah. I used the motors all last year in fights and even after one good fight you can already see the signs of them breaking.