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Author Topic: A possible solution for a tight space  (Read 1633 times)

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Offline Joker94Topic starter

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A possible solution for a tight space
« on: January 22, 2010, 05:53:45 AM »
Hi every one

I recently recived my tank treads in the mail so my current quest is to design a structure for the treads.

My problem is space as the rods weren't long as i thought.  I cant have both servos at the back so in my CAD i have one at each end.

I just want to know what people think of this. I am thinking it will be not a big deal as all code i write i can  make to fit my mechanical needs and if i want to use it on another platform i'll be able to change the values to compensate as i will include comments.

Thanks Joker94

Offline little-c

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Re: A possible solution for a tight space
« Reply #1 on: January 22, 2010, 08:25:11 AM »
you have no method of making the chassis wider?

how about gearing the servos through 90 degrees?
you do have issues with how the torque works. one side will be pulling up, and the other back. think about how the treads work.

software fudgeing would make it work.

Offline Joker94Topic starter

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Re: A possible solution for a tight space
« Reply #2 on: January 22, 2010, 05:09:50 PM »
I am pretty sure i can not make it any wider as the rods that come with it are only app 98mm so my inside space is quite small.

Another idea i have had is if i mount both servos at the back on the out side of the structure in front of the sprockets and connected via timming belts or something that will achieve the same effect.  I am not fssed about the asthetics at the moment as there will be an outer shell. At the moment i am just setting up the treads.

I will come up with a CAD ASAP.

Thanks Joker94

Offline little-c

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Re: A possible solution for a tight space
« Reply #3 on: January 23, 2010, 05:48:59 AM »
if you did a bike chain type link, you could place the servos on top of the treads. or stagger them. one in front of the other with a chain going from each servo to its sprocket.

I love how blatently obvious ideas aren't.  ::)

Offline dunk

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Re: A possible solution for a tight space
« Reply #4 on: January 24, 2010, 01:25:17 AM »
hi Joker,
remember that the higher the length to width ratio you make your chassis the worse the bot will turn.

as a thought experiment compare the turning ability of a single axle with a wheel at either end to your current chassis design.

which of these will turn better?
this (single axle with wheel on either end):   
|-----|

or this:
|-|
 :
 :
|-|

i don't know if i'm making this clear but i advise you make your chassis as short and wide as possible.


dunk.

Offline Joker94Topic starter

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Re: A possible solution for a tight space
« Reply #5 on: January 24, 2010, 03:19:21 AM »
Yeah I understand what your getting at.

As i am currently limited by the axle lengths an option might be to get another 3mm rod and cut it to the length that i want as i know my local hobby shop will have a 3mm metal rod i can use

I have specifically designed the shape of the treads to add  stability but also provide some ability to handle obsiticls Eg. smallrods etc.

what do you think about the "make my own length rods idea". will it be a suitable solutioin. i am thinking that it should be fine.

Thnaks alot

Joker94

Offline Joker94Topic starter

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Re: A possible solution for a tight space
« Reply #6 on: January 25, 2010, 04:05:54 AM »
Well today i got some 3mm rod  so i can make my own axles to solve my problem of  a tight space and stability from a narrow base.

i have my brackets/track support structures designed and ready to make.

I'll report back on my progress.

Thanks Joker94

 


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