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Unread 23-01-2010, 01:28
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Re: Mecanum wheels friction coeff- will it work?

Quote:
Originally Posted by Ether View Post
Is it my imagination, or are both Figure 2 and Figure 4 in the following link incorrect:

http://www.scipub.org/fulltext/ajas/ajas351831-1835.pdf
Figure 4 is definitely wrong. I think that robot would have real difficulty going straight.

Figure 2 might be wrong, or it might just be a bottom view. Since it's showing the force vectors, it actually makes sense to be showing the spot where the wheels contact the floor.
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Unread 23-01-2010, 07:53
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Re: Mecanum wheels friction coeff- will it work?

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Originally Posted by Alan Anderson View Post
Figure 2 might be wrong, or it might just be a bottom view. Since it's showing the force vectors, it actually makes sense to be showing the spot where the wheels contact the floor.
OK, agreed, if it's bottom view it's OK. If it's top view it's not going to spin in place well. The side vectors will be trying to spin in one direction while the forward/reverse vectors will be trying to spin in the other.


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Last edited by Ether : 23-01-2010 at 22:43. Reason: correction
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Unread 23-01-2010, 16:23
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Re: Mecanum wheels friction coeff- will it work?

the only mechanum problems we've encountered is that they don't fit into the KOP brackets, but we're already at work on that
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Unread 23-01-2010, 17:52
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Re: Mecanum wheels friction coeff- will it work?

Having done the calculations, and real world testing, Team 1716 has found that the 8" mecanum wheels will successfuly go over the hump. Unfortunatly we did have to modify the KOP wheel brackets. Once that had been accomplished, we had no problems!

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Unread 23-01-2010, 19:40
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Re: Mecanum wheels friction coeff- will it work?

Quote:
Originally Posted by McGurky View Post
Having done the calculations, and real world testing, Team 1716 has found that the 8" mecanum wheels will successfuly go over the hump. Unfortunatly we did have to modify the KOP wheel brackets. Once that had been accomplished, we had no problems!

Happy Building
-Mcgurky

Just curious... How are you planning on configuring your operator interface for controlling the mecanum wheels?

e.g.

Joystick1 y-axis controls fwd/rev for all 4 wheels and
Joystick1 x-axis controls right/left slide and
Joystick2 x-axis control right/left spin

OR

Joystick1 y-axis controls fwd/rev for left wheels and
Joystick2 y-axis controls fwd/rev for right wheels and
Joystick1 x-axis controls right/left slide

OR

something else??



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Unread 23-01-2010, 21:35
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Re: Mecanum wheels friction coeff- will it work?

we are using a single 3 Axis Joystick vs. the ones provided in the KOP.

y-Axis=Forward/Reverse
x-Axis=Left/Right
"z"-Axis=Spin Left/Right

We are using a Joystick similar to this in which you can spin the joystick left and right.

Hope this helps!
-McGurky
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