This repository about real-time optimization of input link length for 4bar linkage based quadruped robots.
We suggest new mechanism that adjust input link length using sub actuator and optimal length control method.
Youtube Video1 / Youtube Video2
3D CAD Modeling
Metal Modeling (Stainless steel + Aluminium)
Hip (AK80-9 Motor)
Knee (AK80-9 Motor)
Input Link Length (BL2446S Motor)
- Motor control on MATLAB Simulink R2024a
- TI launchpad f28379d Motor Driver
coming soon
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Our Method
We optimized the input link length under the constraint of motor.
First, we focused on a sit and stand task using position control.
We determined the trajectory of end effector to carry out sit and stand task.
Then, we obtained the angle trajectory of 2 main motor(hip and knee) by solving inverse kinematics of legs.To optimize the input link length, we set the constrained optimization problem as like below.
All constraint from the specification of hardware.
Our main optimization purpose is reducing energy consumtion.
We know about the torque term from model dynamics.
All the things are same as other quadruped robot leg except the knee torque term.
Non-liner function f determined on the convex plane.
We know the initial point on the plane.
And we already know the next time step theta_2 (knee theta)
We can determine the optimal length L1 that maximize f term under constraint.
By solving constrained optimization problem, we can get the optimal link length that minimizing energy consumption.
coming soon
By integrating the absolute value of the current over time to compare energy consumption, the application of optimization resulted in a 29.4% reduction in energy consumption.
