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### Author Topic: holonomic mobile robot  (Read 2112 times)

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#### funk1e

• Beginner
• Posts: 3
##### holonomic mobile robot
« on: March 15, 2010, 01:46:32 PM »
hi,
i'm very new here.
my question:
is it possible to built holonomic mobile robot using just 2 Transwheels???
help me. currently i'm using 2 Transwheels. the position of the transwheels are left and right (straight)(my platform more or less like square). is it possible by apply different speed of left and right transwheels so it can move to the side (i'm sure it is possible when it is non-holonomic)

#### GWER57

• Full Member
• Posts: 65
##### Re: holonomic mobile robot
« Reply #1 on: March 15, 2010, 01:51:32 PM »
I think so, but you have to change the directions of one of your wheels to make them at a ninety degree angle. Thus you would have one wheel controlling your movement in the Y-axis (forwards and backwards) and the other the X-axis (left and right). I hope that helps, but you need to know that you need a third contact point so that your robot does not drag!
GTW

#### funk1e

• Beginner
• Posts: 3
##### Re: holonomic mobile robot
« Reply #2 on: March 15, 2010, 02:16:35 PM »
hi GWER57 ,

I think so, but you have to change the directions of one of your wheels to make them at a ninety degree angle. Thus you would have one wheel controlling your movement in the Y-axis (forwards and backwards) and the other the X-axis (left and right).

i think that will be a great idea!
but i already constract the chassis like this:

to turn one of the wheel 90deg seem like alot work to do~ any other idea?
« Last Edit: March 19, 2010, 11:37:34 AM by funk1e »

#### waltr

• Supreme Robot
• Posts: 1,928
##### Re: holonomic mobile robot
« Reply #3 on: March 15, 2010, 02:46:27 PM »
I don't think it is possible with that wheel configuration to get it to move sideways. You need to have the wheels not in line to get a sideways force. I'm not even sure its possible with only two wheels to get sideways movement.

Hopefully someone will post here and prove me wrong.

#### SmAsH

• Supreme Robot
• Posts: 3,959
• SoR's Locale Electronics Nut.
##### Re: holonomic mobile robot
« Reply #4 on: March 15, 2010, 02:58:31 PM »
With that wheel config, it cannot move sideways on its own, it can roll sideways but not drive sideways. Waltr is right, you need three omni wheels to achieve sideways motion.
Howdy

#### GWER57

• Full Member
• Posts: 65
##### Re: holonomic mobile robot
« Reply #5 on: March 16, 2010, 08:53:24 AM »
My suggestion is if you don't want to do a lot of modding get rid of the two casters and add two more wheel assemblies where the casters used to be. That is probobly the easiest solution i can think of but make sure to look at admin's robot fuzzy as he uses a basic aluminum suspension to make sure all of the wheels touch the ground .
GTW

• Beginner
• Posts: 3