# Revision history [back]

### What are the units for Joint::SetVelocity

Hi There,

As i understand it Gazebo uses SI units for everything but im confused as to what exactly the unit is for the number given to Joint::SetVelocity.

Im making a robot that has a single steer/drive wheel and im taking inspiration from VehiclePlugin to write my own plugin to control the robot.

What i don't understand is to get my robot to move at 2m/s i set the joint velocity to (2/wheelRadius). as far as i can tell that has units of just second?

I guess i don't really understand what the velocity of the revolute joint is.

If anyone is able to help me out or point me to the right documentation (I can only find the API reference) that would be much appreciated.

Thanks

### What are the units for Joint::SetVelocity

Hi There,

As i understand it Gazebo uses SI units for everything but im confused as to what exactly the unit is for the number given to Joint::SetVelocity.

Im making a robot that has a single steer/drive wheel and im taking inspiration from VehiclePlugin to write my own plugin to control the robot.

What i don't understand is to get my robot to move at 2m/s i set the joint velocity to (2/wheelRadius). as far as i can tell that has units of just second?

I guess i don't really understand what the velocity of the revolute joint is.

If anyone is able to help me out or point me to the right documentation (I can only find the API reference) that would be much appreciated.

Thanks

### What are the units for Joint::SetVelocity

Hi There,

As i understand it Gazebo uses SI units for everything but im confused as to what exactly the unit is for the number given to Joint::SetVelocity.

Im making a robot that has a single steer/drive wheel and im taking inspiration from VehiclePlugin to write my own plugin to control the robot.

What i don't understand is to get my robot to move at 2m/s i set the joint velocity to (2/wheelRadius). as far as i can tell that has units of just second?

I guess i don't really understand what the velocity of the revolute joint is.

If anyone is able to help me out or point me to the right documentation (I can only find the API reference) that would be much appreciated.

Thanks