popi-mkx3 / popi_project

Here is everything you need to know about POPI, our open-source quadruped robot. If you want to check the videos we will release about it, you can have a look at our YouTube channel.
https://www.youtube.com/channel/UCaCy-1MX6SoqdtjZH4uU_TA
BSD 3-Clause "New" or "Revised" License
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Popi's Equation of motion in every gaits of legs and base. #3

Closed UchidaKouki closed 3 years ago

UchidaKouki commented 3 years ago

Hello, everyone. I have a new question about Popi. I want to know about Popi's equation of motion in every gaits of legs and base. I'm a collage student and studying about 4-legged robot simulation.

Popi simulates motion and path of robot by using system of Towr. I found this repogitory during studying about Towr. ALEXANDER in ETH Zurich published paper about kinematics of 4-legged robot, Towr and Xpp He also introduced the paper in his repogitory.

Robot models of Popi is deferent from Xpp, so I searched paper which wrote about Popi, because I want to study Popi's kinematics anew. But I couldn't find the paper in the web. I apologize my low level ability of searching paper.

If you published the paper which wrote about Popi's kinematics or equation of motion in formula, can you tell me where is the paper? If possible, please tell me about Popi's kinematics or equation of motion in this issue?

popi-mkx3 commented 3 years ago

Hello HuchidaKouki,

Sorry about that, we actually did not publish any paper about Popi's kinematics. The equations are located here , just in case you didn't find them.

I actually calculated those equations using the modified Denavit-Hartemberg method, but it was all handwriting, backed up by long-lost Matlab's files. I am currently lacking the time to put the whole work into a numerical format, but I just quickly rewrote the transformation matrix using the modified Denavit-Hartemberg convention, so that you can give it a try. You should easily come up to the solution.

Transformation matrix.pdf

Please let me know if this is enough to help you. Otherwise I will do my best to find some more time.

With regards, Lucas