Submitted by Asellith on February 4, 2010 - 9:20pm.
Wheel and Sensor Mounting
The frame is designed to be experimental. Nothing is permanent and can be moved
where needed. The wheels are about the only important part that cannot
be moved. As I mentioned earlier I mounted the servos in Aluminum U
channel. However servos don't get you very far without wheels. I found
a tutorial on mounting the omniwheels to the servos here:
http://www.acroname.com/robotics/info/ideas/omnimod/omni_mod.html
However I didn't like the design so I modified it slightly. I didn't use the
finishing washer. I just used a standard locking washer. Also I tried
the nylon bolts but found them lacking in stability and strength so I
upgraded them to steel bolts. These work great and have not failed me
yet.
This small metal connector can be found at your local hardware store. Its called a T-nut. They work great. I bought this one at Lowes.
A big issue was finding a round servo horn. I finally had to break down and buy a bag of miscellaneous servo horns from
two different hobby stores in two different states. Hobbytown USA sells
them but I couldn't find them for much cheaper individually online.
This way I have a few extra horn types for other projects.
 |
The small metal peice is called a T-nut. They can be found at hardware stores. I purchased these ones at Lowes. They work great.
| From ExMod |
The servo horn screw didn't fit through the T-nut so I had to put it under
the T-nut and bolt that down before I screwed it into the servo. A bit
of a pain but the added benefit that you can't loose the screws. That
was the hard part the rest is done by threading the other T-nut onto
the bolt and screwing the bolt into the servo horn's nut. Don't forget
the lock washer to keep things tight. Remember the idea is not to
tighten it down as tight as possible but to secure the omniwheel to the
servo. Watch you don't get over excited and damage your wheels.
