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kawal24
08-28-2011, 04:40 PM
Hi,
I am using these rubber tracks (http://robokits.co.in/shop/index.php?main_page=product_info&cPath=57&products_id=193&zenid=56c1c392c353e96a913507a84f02d2cf) and pulleys (http://robokits.co.in/shop/index.php?main_page=product_info&cPath=57&products_id=192&zenid=56c1c392c353e96a913507a84f02d2cf) but the rubber track belt is slipping off the wheel(pulley) even when the belt is too tight.
Is there a way to solve this problem.

Thanks

vikas
08-28-2011, 05:37 PM
Use a medium grit sand paper and sand the pully , it will make the pully very rough and cause a lot of friction.

Other wise use a wheel with grooves on it as a pully.

kawal24
08-28-2011, 06:23 PM
Sanding the pulley seems to be a good idea.
Btw by "slipping" i meant the track belts are "getting off" the wheels.

devdatta
08-28-2011, 07:50 PM
check alignment of wheels....

maddy_nish
08-28-2011, 09:18 PM
Hi,

Even i had a similar problem three years ago while using almost a similar belt. Please note the following

1) Belt slips because it extends while in motion
2) The extension in the belt is a function of friction between belt and ground, load on the bot, the tension in the belt(how tight it is), difference in tension at the slack side and tight side.
2) Every belt can handle only a limited tension depending on its stifness
3) No matter how tight you make it, how rough the pulleys are, it would slip off due to its limited stiffness.
4) Either reduce the load on the bot which in turn would reduce the tension in the belt or use a stiffer belt.
See if you can get belt of greater thickness and width hence you would find a stiffer belt.

kawal24
08-28-2011, 10:23 PM
Ok robokits has wider track belts also (4 cm width).So do you want to say that these wider belts wont get off the wheels/pulleys ?

maddy_nish
08-28-2011, 10:40 PM
Once again, consider the above points load,stifness, friction. Actualy the belt in the site is automobile timing belt. They can only be used on a very small loads. Not it to be used on larger load. It is originally used just on an ordinary pulley. Not as track belts. Track betls in general need to be stiffer.
What i would suggest you is to try Polyurethane belts. You can easily fix the ends together by heating over a flame.They are quite stiff, can easily handle loads..

vikas
08-29-2011, 12:54 PM
You can make these ones , cheap and solid. But take time to make.

http://letsmakerobots.com/node/21908

They will not fall off , like i think is happenign in current case.

The current setup has no locking to keep tracks on wheels. Either use grooved wheels with thick tracks or the above approach.

kawal24
08-29-2011, 05:37 PM
A while ago i made those tracks but completed only one side and then i didnt get time to work on it.
heres a image
http://communityofrobots.com/sites/default/files/images/u1/display.jpg

I was thinking to make that type of tracks early but i am not having that much time due to college.
But then again i dont have any other choice.
I'll get my work started today rather than wasting time on thinking what to use and what not to use .

endlasuresh
08-30-2011, 10:49 AM
Sanding the pulley seems to be a good idea.
Btw by "slipping" i meant the track belts are "getting off" the wheels.
Yeah they wont stand on the pulley. Just look at tractors how pulley are used.The chain you posted seems to be good but it weights a lot and you even need sprockets.

kawal24
08-30-2011, 11:34 PM
They dont require sprockets.Just put it on top of rubber wheels and friction does the rest of the work.