This paper presents the position-based force control application of a mobile manipulator. The mobile manipulator consists of two six DOF manipulators and a mobile robot. Kinematics of the robot is analyzed and simulated to validate the analysis. A position-based force control technique is applied to the robot by adding an outer loop to interact with the environment. Experimental studies of force control applications of robot arm and interaction with a human operator are conducted. Experimental results show that the robot arm is well regulated to follow the desired force.