# Revision history [back]

### contact force changing rapidly for a basic box shape on ground plane

Hi all,

In my simulation I have a simple box on the ground plane with the following parameters:

Dimensions: 1[m]x1[m]x1[m]
Moment of Inertia: ixx=0.166666667 iyy=0.166666667 izz=0.166666667
Mass: 1[kg]


As seen from this youtube video the contact forces are oscillating for this simple setup. Using the ros bumper plugin it was confirmed on rviz (youtube video) as well. When the moment of inertia was changed to deafult values (ixx=1.0 iyy=1.0 izz=1.0) there was no such oscillations as seen by:C:\fakepath\gazebo-stable.jpg

According to ODE wiki ODE engine has an accuracy issue. So, does that mean I cannot use it for example, calculating collision forces, torques in simulation?

Can anyone let me know some examples where collision forces have been used apart from ros bumper plugin.

Thank you in advance.

Peshala

### contact force changing rapidly forces oscillating for a basic box shape on ground plane

Hi all,

In my simulation I have a simple box on the ground plane with the following parameters:

Dimensions: 1[m]x1[m]x1[m]
Moment of Inertia: ixx=0.166666667 iyy=0.166666667 izz=0.166666667
Mass: 1[kg]


As seen from this youtube video the contact forces are oscillating for this simple setup. Using the ros bumper plugin it was confirmed on rviz (youtube video) as well. When the moment of inertia was changed to deafult values (ixx=1.0 iyy=1.0 izz=1.0) there was no such oscillations as seen by:C:\fakepath\gazebo-stable.jpg

According to ODE wiki ODE engine has an accuracy issue. So, does that mean I cannot use it for example, calculating collision forces, torques in simulation?

Can anyone let me know some examples where collision forces have been used apart from ros bumper plugin.

Thank you in advance.

Peshala

### contact forces oscillating for a basic box shape on ground plane

Hi all,

In my simulation I have a simple box on the ground plane with the following parameters:

Dimensions: 1[m]x1[m]x1[m]
Moment of Inertia: ixx=0.166666667 iyy=0.166666667 izz=0.166666667
Mass: 1[kg]


As seen from this youtube video the contact forces are oscillating for this simple setup. Using the ros bumper plugin it was confirmed on rviz (youtube video) as well. When the moment of inertia was changed to deafult values (ixx=1.0 iyy=1.0 izz=1.0) there was no such oscillations as seen by:C:\fakepath\gazebo-stable.jpg

According to ODE wiki ODE engine has an accuracy issue. So, does that mean I cannot use it for example, calculating collision forces, torques in simulation?

Can anyone let me know some examples where collision forces have been used apart from ros bumper plugin.

Thank you in advance.

Peshala

ps: I am using ros hydro with gazebo 1.9