Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Maybe I find a bug! #1

Open
Mike1425217072 opened this issue Nov 16, 2020 · 1 comment
Open

Maybe I find a bug! #1

Mike1425217072 opened this issue Nov 16, 2020 · 1 comment

Comments

@Mike1425217072
Copy link

In
function [t0dot,tLdot]=Accelerations(t0,tL,P0,pm,Bi0,Bij,u0,um,u0dot,umdot,robot)

line 49,
%Base-link
Omega0=[SkewSym(t0(1:3)), zeros(3,3);
zeros(3,3), zeros(3,3)];

This should be:

Omega0=[SkewSym(t0(1:3)), zeros(3,3);
zeros(3,3), SkewSym(t0(1:3))];

right?

@YukiCR
Copy link

YukiCR commented Mar 12, 2024

Hi,
as far as I'm concerned, the calculation of Omega0 is right.
in line 63, we have

t0dot = Omega0*P0*u0+P0*u0dot;

which is
$\dot{t}_0 = (\Omega_0 P_0 )u_0+ P_0 \dot{u}_0$.
so Omega0*P0 should be $\frac{\mathrm{d}}{\mathrm{d}t}P_0$,
since P0 is

[R,           zeros(3);
 zeros(3),   eye(3)];

it's derivative will be the derivative of the top left part of P0, i.e,
R_dot = SkewSym(t0(1:3))*R

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants