In this paper, the position and force control of constrafined motion of robotic manipulators is discussed. First, issues related to decoupling position and force-controlled directions are discussed. The fundamentals of estimation of the contact force without using force or torque sensors are then presented, and a control scheme for position and force control of robotic manipulators without using force sensors is proposed. The extension of this scheme to redundant manipulators is also discussed. Finally, the proposed control scheme is implemented on a 3-DOF planar redundant manipulator, and the experimental results illustrate the validity of the control scheme.