Not sure I understand your question, so I am going to assume you have two motors driving the wheels and a third motor for the robot arm. 

If you move the arm down using the regulated motor control blocks, the default is that the motor brakes after it has moved x rotations/degrees/seconds. The effect of that may be that it actually pushes the arm down against the floor. 

If this is the case, you could try changing the end-of-motor-movement action from braking to coasting and see if that helps. 

On Sunday, November 9, 2014, Heather Young <[log in to unmask]> wrote:
My team is having a hard time making the robot move once the arm is down.  Can anyone help us?
 
Thanks,
Heather Young
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