Xlrobots.com Zero-rov-r!

 
#21

Ah... ok... gotcha. Sorry dude... good work on the design...

#22

@rich I looked at almost all the omni designs and the look i liked most was the style i made my version in. the others dont look like wheels anymore they look alien if that. plus the omni-wheel would also be a cool upgrade for the omnibot drive train wheels. i can make the wheel the exact size of the omnibots but make them omni wheels.

#23

It doesn't really matter what they are for, they will function the same regardless of what they are on. The smaller wheels need to be angled for the wheels to work correctly.

I may be teaching to suck eggs here but I'll explain anyway...

Imagine your normal drive train, you have forward, reverse, rotate left (skid steer) and rotate right (skid steer).

With Omniwheels you have the above but also the ability to move left and right as well as rotate left and right. By moving the front wheels in the opposite direction to the rear wheels the omniwheels will move the robot either left or right along with angles without rotation.

With 90 degree "inner wheels" the robot will not do that, it'll be a jerky, lumpy, irregular fight between the front drive and rear drive. Nothing can make it move left or right unless the wheels are at an angle.

I'm not convinced that explanation has explained well enough, I'm pushed for time right now so my usual level of detail and clarity may not have applied. With that in mind, a video example paints a thousand words...


#24

I personally am not wild about using omni wheels for a robot because usually the goal is autonomous operation and the omni wheels only cater to certain surfaces. I realize that some people like them because the concept of going sideways is cool.

Someone pointed out how they handle off road or carpet. I have watched videos of others and as long as carpet is short pile omni wheels will work , tall pile , shaggy or plush not as well and both from carpet and outdoors there Is risk of entanglement from fibers , dirt or other mysterious junk between all the little wheels. So they serve their purpose but they are not all terrain Smile

#25

Omniwheels will drive on the same surfaces any other wheel will drive on provided the correct ones are selected. They can also be usefull for autonomous robots or for manual movement. I can think of alot of things where sideways movement would be usefull. I have planned to use omniwheels on Melvin for about a year, he is 100% autonomous. The sideways movement will work very well with the side sensors and object avoidance scripts.

#26

Omniwheels were one of those tested tested for zero rover and the other base I'm working on, they didn't perform correctly on uneven terrain , loose surface like pebbles ,gravel, grass, dirt, plush carpet and transition from a lower to a higher surface slipped unless there was a running start. The testing I was able to play with all kinds of wheels in a RC store that had a large selection. The omniwheels just don't have grip like regular wheels but by all means use them if they are what you want. They will work on your hardwood floors or tile great. They just are not for me at this time. I need a wheel with wider range of use , heavier weight capacity is one of them.