Hello, Practically with fixed body robot, when dynamics are calculated by using recursive newton-euler, each joint is defined as 1 hinge joint with a link so that the model has one joint parameter including mass, inertia. However, floating body robot has 6 DoF and it should be defined in one variable i suppose? I would like to know how you defined 6 DoF of floating body in the program when you calculate dynamics using RNE. Thank you.
There is joint type "free" which creates a floating body. See documentation here: http://www.mujoco.org/book/index.html#Floating
hi, i wonder is there any mistakes : i model a floating base using "joint type=free", but the next one link attached just go through it, with out contact detection. however, the other links seems fine, just like the picture. and here is my code Code: <worldbody> <light pos="0 1 1" dir="0 -1 -1" diffuse="1 1 1"/> <body name="base"> <joint type="free" /> <geom type="box" pos="0 0 0" size="0.3 0.3 0.3"/> <body name="link_1"> <joint name="joint_1" type="hinge" pos="0 0.3 0" axis="1 0 0"/> <geom type="capsule" fromto="0 0.3 0 0 1.3 0" size="0.02"/> <body name="link2"> <joint name="joint_2" type="hinge" pos="0 1.3 0" axis="1 0 0"/> <geom type="capsule" fromto="0 1.3 0 0 2.5 0.5" size="0.01"/> </body> </body> </body> </worldbody> thanks!