Let's Make Robots!

Tri-wheel stair climber


It seems to me that for a robot to be really useful in the home or workplace then it must be able to handle stairs. With this in mind I want to design a stair climbing robot chassis. This robot is my first experiment with Tri-wheels.

The chassis is just 4x Wild Thumper 75:1 motors driven by a Wild Thumper controller in a clear acrylic base. As this is only an experimental platform for the wheels I am controlling it with a TV remote and an IR receiver.

This first set of Tri-wheels is made using a new 80mm diameter wheel that has been produced by DAGU. The gears are steel to handle the high torque required when climbing.

The clear triangular frame is made from 3mm thick milled polycarbonate. I used CNC milled polycarbonate instead of laser cut acrylic because it is tougher. The acrylic is fine for the chassis but too brittle for the wheels. All shafts are ball raced to reduce friction.

You can see here that the chassis consist of 4 ribs, a top plate and a bottom plate. They are all held together by 56 small steel angle brackets and 112 small M2x5 screws that give the chassis good strength and rigidity. In hind sight I could have used less but this is just a prototype.

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I read that book. It does seem to have the same form as the vehicle on the cover. Damnation Alley, holy.

Ultimately I am working on a balancing robot using a Tri-wheel. This would not need the center pivot.

i needed this and i still do... i dunno what it is called so when i look for it i had to describe it and i always end up being shown a random set of gears

this is cool

 

Please give us a video. It'll be nice to see it in action.

One thing I'm not able to understand is, why will the wheels turn forward and "climb onto the next stair". Also, can't this be done by 2 sets of tri wheels instead of 4 (you have 4 motors mounted to your chassis).

This is a work in progress. I am waiting for more tires to arrive.  Yes, you could use only two tri-wheels if the robot is a balacing robot. That is my next project. For now I am using 4 wheels for simplicity.