The development of a new class of high-speed cable-based manipulators is presented in this thesis and fundamental challenges specific to these manipulators are addressed. Cables are used in the architecture of these manipulators to provide kinematic constraints to lower the number of degrees of freedom and minimize the moving inertia. Five new designs of these manipulators are presented which provide pure translational motion in spatial and planar workspace. Since cables can only stand tensile forces, the rigidity of the cable-based manipulators becomes the most essential issue in their design and operation. To address this, a systematic approach to study the rigidity of these manipulators is developed. It is analytically proved that most of these manipulators stay rigid everywhere in their workspace under any external load using a spinal element that applies a constant pushing force on the end-effector.; Geometry is used in this work to develop a modeling approach to investigate the ability of cable-based manipulators in the handling of payloads. Force and torque capacity of these manipulators are defined as the set of all forces and/or torques they can apply before losing their rigidity. Based on this, an optimum design procedure is developed for determining the pretension of the cables when a symmetric force/torque capacity is required.; The stiffness and stability of cable-based manipulators are also studied. It is shown that the cables' pretension, necessary for the rigidity of these manipulators, affects the stiffness of the manipulator and hence, may result in their instability. The conditions under which the manipulator is stabilizable are derived. A stabilizable manipulator never becomes unstable due to increasing the pretension of the cables.; Trajectory planning of cable-based manipulators is also investigated. A time-optimal trajectory is found considering the condition of the cable tensions. Time-optimal technique along with a non-optimal but more computationally efficient method for real-time trajectory planning are implemented and compared on DeltaBot. DeltaBot is a cable-based manipulator prototyped in this research. It has three translational degrees of freedom and is aimed at high-speed pick-and-place applications. DeltaBot is designed to be able to produce 4g of acceleration everywhere in its workspace in any direction on a pay load of 1kg. DeltaBot has been successfully tested for 120 cycles of pick-and-place operations per minute.
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