Leg Design & Assembly

Check out the videos above for a recap of my older walking robots and the concept behind this design. The third video details the start of the leg construction. I’ve used parallelograms for the top and bottom of the leg as I did in some of the older designs that worked the best:

The gear arrangement I discovered in video part 2 has been implemented inside each parallelogram:

I used Nylon bushing printed in Taulman Alloy 910 to make bushings for the joints:

Here are the assembled legs – they need hips and ankles installing which will have additional joints:

I’ve built the hips and ankles. These are essentially the same parts reversed so that the speed and torque is equal. I’ve used the maximum leverage angle possible by hinging both the hips and ankles in the middle and placing toothed tracks/racks on the outside, which the motors run around.

The toothed tracks hold the joints in position well – they are worm gear driven motors & gearboxes, so they do not back-drive.

The hips allow the legs to rotate on a vertical axis so the robot can turn on the spot and walk in a curve. For now they are left zip-tied together at the front, but if the whole thing can walk in a straight line fine I’ll add that mechanism later.