ShuoYangRobotics / A1-QP-MPC-Controller

An open source implementation of MIT Cheetah 3 controllers
GNU Affero General Public License v3.0
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Why are the parameter "a1_robot_mass" different in config folders? #11

Closed ch1102256774 closed 2 years ago

ch1102256774 commented 2 years ago

Hello, i found that the parameter "a1_robot_mass" is different in the "config" folder's yaml files. In "gazebo_a1_mpc.yaml" and "gazebo_a1_mpc.yaml"(line 6), the value is 12.0 :

# physics parameters

a1_robot_mass: 12.0 

but in "hardware_a1_mpc.yaml" and "hardware_a1_mpc.yaml", the value has changed to 13.5 and 15.0

# physics parameters(qp)

a1_robot_mass: 15.0
————————————————————————————————————————
# physics parameters(mpc)

a1_robot_mass: 13.5

i want to know why the mass is different in two methods. Besides, i also found that the parameter "a1_trunk_inertia_xx" is also different in in "hardware_a1_mpc.yaml" and in "gazebo_a1_mpc.yaml".

Looking forward to your reply.

ShuoYangRobotics commented 2 years ago

Because my hardware robot has a different mass and inertia than the robot in gazebo. Your hardware robot may have different mass/inertia properties depends on what payload you have. You should change them accordingly.