Bilateral teleoperation systems have been extensively utilized for implementing tasks in remote or hazardous environments. However, due to the cognitive limitations of the human operator, efficient teleoperation of complex robotic system operating in cluttered environments has been difficult to achieve. In this paper, we study the control problem of a semi-autonomous teleoperation system, where the redundant slave robot can autonomously satisfy several constraints while tracking the position of the master robot in the task space. Considering heterogeneous master and slave robots, we first develop a control algorithm to ensure task space position and velocity tracking between the master and slave robots in the presence of dynamic uncertainties and communication delays. The redundancy of the slave robot is then utilized for achieving sub-task control, such as singularity avoidance, joint limits, and collision avoidance. The control algorithms for the proposed semi-autonomous teleoperation system are validated using numerical simulations on a non-redundant master and a redundant slave robot.