Why are not jacob0 and pin.WORLD consistent for computing jacobian wrt the world frame?

[LHTLiu]

Hi!

My setup
Chip: Apple M1 Pro
macOS: Sequoia 15.0
PyCharm 2024.2.1 (Community Edition)
matlab: R2021b
pinocchio: 3.2.0

My question: I use Pinocchio and [robotics toolbox 10.4](https://petercorke.com/toolboxes/robotics-toolbox/) of matlab for my research on forward kinematics and jacobian matrix of the same position of Franka. And i found that the forward kinematics were consistent, but the function jacobe relative to the local coordinate system in matlab is the same as pin.LOCAL in pinocchio. The function jacob0 in matlab relative to the world coordinate system is the same as pin.LOCAL WORLD ALIGNED in Pinocchio.

Why are not jacob0 and pin.WORLD consistent?

what’s going on?

In Pinocchio

Flange_pose = data.oMf[Flange_Id]
print("Flange_pose \n", Flange_pose)

Flange_Jaco_wrt_local = pin.computeFrameJacobian(model, data, q, Flange_Id, pin.LOCAL)
print("Flange_Jaco_wrt_local \n", Flange_Jaco_wrt_local)


Flange_Jaco_wrt_world = pin.computeFrameJacobian(model, data, q, Flange_Id, pin.LOCAL_WORLD_ALIGNED)
print("Flange_Jaco_wrt_world \n", Flange_Jaco_wrt_world)

In matlab

mdl_panda

panda.tool.t = [0;0;0];

q = [0.1,0.2,0.3,0.4,0.5,0.6,0.7];

panda.fkine(q)

panda.jacob0(q)
panda.jacobe(q)

Thanks

@jviereck @jcarpent

[jcarpent]

Why are not jacob0 and pin.WORLD consistent?

pin.WORLD represent the point coincident with the origin of the WORLD as moving with the body.
pin.LOCAL_WORLD_ALIGNED is centered on the point of the moving body in the coordinate systems with axes aligned with the WORLD frame.

[LHTLiu]

thanks for your reply. but i don't think you've solved my question.
@jcarpent
don't give me the definition.

the result of the jacob0 of the Matlab . The results of matlab's jcaob0 function are actually consistent with the results of pinocchio's pin.LOCAL_WORLD_ALIGNED. Why aren't the results of matlab's jcaob0 function consistent with the results of pinocchio's pin.WORLD?

thanks

[LHTLiu]

@jcarpent , hello, can you help me solve my question? Thanks.