Estimating the inertia matrix for the bracket
Posted: Mon Aug 24, 2020 2:35 pm
Hi all!
I am updating the HRDF for my hebi arm kit. The arm adds one more joint to the standard 6-DOF kit. Because our application requires high-accuracy modeling, I replaced the brackets and links in the hrdf file with custom rigid body whose transformation parameters represent more accurately our setup.
I hope to use the get_grav_comp function that comes with the Hebi API which uses the inertia matrix in the updated HRDF file. I need to know how to estimate the inertia matrix for the brackets and links that I replaced. The parameters don't need to be very accurate, as long as they are accurate enough for the get_grav_comp function.
My hebi arm used the X5HeavyRightOutside, X5LightRight and X5LightLeft brackets and the X5 extension links. I attached a previous version of my HRDF to show my set up.
Right now, I use the following code to modify this HRDF. Note that I used an identity matrix as inertia for now.
If you can tell us how to roughly estimate the inertia or at least the CoM it would be great!
Best
Kay
I am updating the HRDF for my hebi arm kit. The arm adds one more joint to the standard 6-DOF kit. Because our application requires high-accuracy modeling, I replaced the brackets and links in the hrdf file with custom rigid body whose transformation parameters represent more accurately our setup.
I hope to use the get_grav_comp function that comes with the Hebi API which uses the inertia matrix in the updated HRDF file. I need to know how to estimate the inertia matrix for the brackets and links that I replaced. The parameters don't need to be very accurate, as long as they are accurate enough for the get_grav_comp function.
My hebi arm used the X5HeavyRightOutside, X5LightRight and X5LightLeft brackets and the X5 extension links. I attached a previous version of my HRDF to show my set up.
Right now, I use the following code to modify this HRDF. Note that I used an identity matrix as inertia for now.
Code: Select all
newmodel.add_actuator('X8-16')
DH_transformation=get_DH_transformation(FK[1,0],FK[1,1],FK[1,2]-0.0451,0)
newmodel.add_rigid_body(np.identity(4), np.ones(6), 1.0,
DH_transformation, False)
newmodel.add_actuator('X8-9')
Best
Kay