Episode 538: How to Build a Quadruped Robot - NO MATH!

well my design was based on ...nothing really I just winged it. A square overall shape would have been easier to work with in hinsight. the robot now tends to fall bawards on long steps.
If I d do another one I'd put more time into the mechanical design from a theoretical base.

A great robot. The design of the legs looks interesting. I might have to have a closer look to see if there are any ideas I can borrow. I have had a number of goes at designing my own 3D printed walking robot, see photograph. I didn't get very far as I was still struggling with the 3D printer at the time, plus I wanted to minimise the number of servos - in my case to only 8. I've since given up on trying to minimise servos and use as many as I like with a PCA9685 16 channel PWM pcb (which works well) with a biped robot I am playing with. 

I did work out that if the four legged robot was square rather than oblong, then it is just about possible to balance of three legs freeing up the remaining leg to be moved forward. In this way the robot is able to 'walk' without having to ground the base. I did not quite manage to get it going as it all depended on where the centre of gravity is and I had not yet placed the batteries. I might have to return to it some time to see if I can do better.

Dubbie

this must be the comment that was stuck in moderation.
Yes I indeed know about that project, but I wanted to focus on the simplest approach first, just to get going.
maybe I do a "dog" version down the line with compliant joints, but fiorst I have to get alot more comfortabel with the usage of match in code.

sure have! maybe Ill try a very coded version that works with compliant joints down the line.

Have you seen the robot dog projects on James Bruton's YouTube channel ?

Tried to link to them yesterday but the spambot took a dislike to them.

that is indeed true, I might build another version in the future, based on community feedback.

James Bruton did some robot dog projects. Not sure if anything in there might be of interest ? 

Mini Robot Dog

https://www.youtube.com/watch?v=DfBF26DaT-M&list=PLpwJoq86vov_qzmadB1zj6aVKObH3WbeH

openDog Dog Robot

https://www.youtube.com/watch?v=0BoPoWF_FwY&list=PLpwJoq86vov_PkA0bla0eiUTsCAPi_mZf

openDog V2

https://www.youtube.com/watch?v=nwqSjMttcSg&list=PLpwJoq86vov9CcmrLGyM2XyyYDAYG0-Iu

openDog V3

https://www.youtube.com/watch?v=IVpYtyS5Q-k&list=PLpwJoq86vov8uTgd8_WNgBHFpDYemO-OJ

Great project Clem.

There are many ways to use 32 servos to improve the leg articulation and movement.

That type of robot would be a major undertaking, so I think your simple solution is better for what you want to do.

To improve stability, you could introduce an IMU chip that would give you sufficient feedback on all three axes to build a smoother control algorithm for movement.

Given the calculations, you would probably have a slow moving robot, but it would be a better platform for adding your camera.

oh no it gets very advanced

Reinforcement learning ? let math do the math...

Quadruped Robot Locomotion Using DDPG Agent
https://uk.mathworks.com/help/reinforcement-learning/ug/quadruped-robot-locomotion-using-ddpg-gent.html