Page 1 of 1

How to make a simple 4 wheeled vehicule

PostPosted: Tue Nov 22, 2016 8:13 am
by François
Hello,
I'm just starting with UM and as a first vehicle model I would like to make a basic body with four wheels. Thus I created a body, gave it a box image and linked it to the ground with a 6 d.o.f. link.
Then I added 4 wheels, linking them with rotational joints to the body.

All seemed fine but when I try to do the equilibrium test on UM Simulation, my vehicle floats around 50 cm above the ground. :shock:
I think it comes from the tyre special forces which seem to be acting like springs between the ground and the wheels.

I looked in the user's manual in the "Development of vehicle model" section to see how to add a wheel correctly but it just says to link it with a rotaional joint to an other body.

Any idea why this happens and how to fix it ?

Thank you in advance for your feedback.

Best regards,
François

Re: How to make a simple 4 wheeled vehicule

PostPosted: Thu Nov 24, 2016 1:56 am
by François
Finally I found out that the tyre models defined in UM Simulation have their own radius parameter, and in my case it didn't match the radius parameter of my wheels : I had 0.2m radius for the wheels and 0.5m for the tyre model.

Re: How to make a simple 4 wheeled vehicule

PostPosted: Thu Nov 24, 2016 7:38 am
by Alexey Sakalo
Congratulations, you could solve this problem yourself!

Best regards,
Alexey Sakalo