pic: super scooter

[CD47-Bot]

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[mtaman02]

A new use for the chip motors. very creative and the price to have one of these is about $4500 less :-)

[sanddrag]

That is a very cool scooter. I bet it zips along quite fast. Could you PLEASE post some pics of the drive system? Thanks.

[fox46]

Here it is. http://www.chiefdelphi.com/pics/bin/107542728548.jpg Sorry it isn't more "revealing" but the jist of it is the shafts of the two motors have been pressed into either end of a machined aluminum slug, and the aluminum U channel that they're mounted on is hinged. There is a threadded stud that pulls the U channel down, and the aluminum slug that is pressed onto the motor shafts is forced down on the wheel. When the motors run, the aluminum slug rubs aganst the wheel, and spins it. It's a very crude system, but it works surprisingly well. However, there are some inherent problems: If you don't apply enough pressure on the slug, it will slip on the wheel and take chunks out and/or melt the wheel. If you apply too much pressure, you could hurt the CIM motor's bearings. Because of the fact that it is a FRICTION drive, it looses alot of energy as heat, which gets dissapated by the frame. Also because of the constant deformation and wear on the wheel, I go through one every 15 charge cycles or so. - Rotating the wheels every few cycles helps prolong their life.

As for speed, it zipps along - I used to ride it to and from classes, but my school's administration banned me from riding it inside - The excuse "It's a Tech. project" wore off really quickly (I think they're jealous).

[Elgin Clock]

Originally Posted by fox46

s for speed, it zipps along - I used to ride it to and from classes, but my school's administration banned me from riding it inside - The excuse "It's a Tech. project" wore off really quickly (I think they're jealous).

That stinks.. lol

Quick question if I may. How did you make the motors turn the same direction even though they are reveresly mounted from each other??
(if this answer is really simple I'm gonna fell stupid, so please make it sound complex.. lol)
Can I just guess that you hooked one motor positive/positive-negative/negative and the other positive/negative-negative/positive?

[fox46]

Originally Posted by Elgin Clock

Can I just guess that you hooked one motor positive/positive-negative/negative and the other positive/negative-negative/positive?

You guessed correctly

[Elgin Clock]

Originally Posted by fox46

You guessed correctly

Yay.. I'm smart..

Thanks for the info..

[mtaman02]

I am so tempted to build me one of these about how long the batteries good for and aproximate weight

[phrontist]

So if I understand correctly, you essentially press the chia's shaft up against the wheel? Man, that IS crude.

How hard do you think it would be to put some gearing on the back wheel?

[greencactus3]

Originally Posted by phrontist

So if I understand correctly, you essentially press the chia's shaft up against the wheel? Man, that IS crude.

How hard do you think it would be to put some gearing on the back wheel?

just a bit harder than a friction drive.. actually, i think cutting the rear end off completely and rebuidling a whole new rear end with a gearbox would be easier than attempting to squeeze somthing into what is already made compact........
hey! how about some 4 speed gearboxes!! with a clutch, of course so you can really rev it and drop the clutch to burn some rubber..... or in this case, the tires arent rubber are they? well, then.. we need to get black rubber tires so the janitors can yell at us for putting too many rubber marks in the hallways!

[phrontist]

GreenCactus:Genius!

This is an excellent way to get some offseason practice in the fabrication of transmissions!

w00t!

It's got everything going for it:

• It's Cool
• It's an accurate simulation of the stresses endured by a robots gearbox. (A bit tougher I suppose...)
• It's fairly easy
• It's cheap

So now my project is to make one of these with a four speed. A truly cool thing to do would be do make shifting automatic...

[greencactus3]

Originally Posted by fox46

http://www.chiefdelphi.com/pics/bin/107542728548.jpg

i just noticed... are those two batteries? im guessing in parallel? is that just to have more run time? and also just to use up some space left over?
OR, is that running at 24V? many motors can take quite a bit of current abuse without burning... of my whole robotics career..(short, but..) ive only burned two drill motors... and that was during my first OCCRA season. and wheelchair motors, which were supposed to be run at 12V, were fine running at 24V.. for an entire battery charge cycle..well of course they got quite hot, but still they are fine. and ever played with those small motors rated 3V? the ones that come in the small handheld batterypowered fans... well, those, you can run them at 9V for quite a while. i dont think there's more rpm with the 9V than with a 7.2V though. didnt have a way to test it, so just a thought. perhaps sumthing to do with heat and efficiency... soooo, if you run the chips at 24V, how long will they last? anyone tried this before? i dont have any to spare so cant test it myself... id like to know how long itll last with some resistance. not a freespin...

[cadman2k5]

LOL I definately want one of those... my birthday is March 15... if it helps.