Motion Simulation




i'm trying to do a motion simulation of a three wheels system (that's what i've been told it's called, pictures below), both cylinders will turn at the same speed and as a consequence the sphere will also turn and translate on the floor, the objective of this simulation is to calculate the enrgy required to operate the system, but i don't know which type of joint i need to choose between the sphere and each cylinder and the floor.


i will also attach the files below.


PS: the angle alpha is equal to 45°





Thanks in advance.


Helmi Bouali


Re: Motion Simulation

Siemens Genius Siemens Genius
Siemens Genius

Hi Helmi,


It's like  a vehicle on the floor; in this case, you can add:

- A Motion Body (Link) representing a frame joining the motors of each cylindrical wheel (for example a CSYS or a simple line with user defined mass properties).

- Revolute Joints between each wheel and that frame - those joints are driven.

- Then 3D contacts between wheels and sphere, and sphere on Floor. 


To get the whole system moving, you'll likely need:

- more insight or assumptions  on the contact wheel/sphere;how is the sphere connected to the frame? How is power transmitted from wheel to sphere?

- additional joint(s) to get it rolling straight :-)


I would also use version 12 for Analytical contacts.


Have fun,





Gilles Dubourg
Simcenter 3D
Siemens Digital Industry Software