Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large translational workspace and high dynamic performances. The rigid base frame of the CDPR is connected in parallel to the moving platform using cables. However, their orientation workspace is usually limited due to cable/cable and cable/moving platform collisions. This paper deals with the designing, modelling and prototyping of a hybrid robot. This robot, which is composed of a CDPR mounted in series with a Parallel Spherical Wrist (PSW), has both a large translational workspace and an unlimited orientation workspace. It should be noted that the six degrees of freedom (DOFs) motions of the moving platform of the CDPR, namely, the base of the PSW, and the three-DOFs motion of the PSW are actuated by means of eight actuators fixed to the base. As a consequence, the overall system is underactuated and its total mass and inertia in motion is reduced.

Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large translational workspace and high dynamics performances. Their rotational workspace is generally far more limited, however, which can be resolved by using cable loops, as was shown in previous research. In the case of fully-constrained CDPRs, cable loops can induce unwanted torques on the moving-platform, causing it to tilt and move away from its intended position, which we call parasitic tilt. Hence, the orientation accuracy of such robots is usually limited. This paper deals with the design, modelling and prototyping of a planar CDPR with infinite rotations, without parasitic tilt and without an additional motor. This robot, which we call a Cable-Driven Parallel Crane (CDPC), is composed of a mobile platform (MP) with an embedded mechanism and a transmission module. The MP is linked with the frame by a parallelogram of three cables to constrain its orientation, including a cable loop, as well as a fourth cable. The two-degree-of-freedom~(dof) motions of the moving-platform of the CDPC and the internal dof of its embedded mechanism are driven by a total of three actuators, which are fixed to the frame. As a consequence, the overall system is fully-actuated, its total mass and inertia in motion is reduced and it is free of parasitic tilts.

Motion planning for Cable-Driven Parallel Robots (CDPRs) is a challenging task due to various restrictions on cable tensions, collisions and obstacle avoidance. The presented work aims at proposing an optimal path planning strategy in order to both maximize the wrench capability and the dexterity of the robot in a cluttered environment. First, an asymptoticallyoptimal path finding method based on a variant of rapidly exploring random trees (RRT) is implemented along with the GilbertJohnsonKeerthi (GJK) algorithm to account for the collision detections. Then, a goal biased Artificial Field Guide (AFG) is employed to reduce convergence time and ensure directional exploration. Finally, a post-processing algorithm is added to get a short and smooth resultant path by fitting appropriate splines. The proposed path planning strategy is analyzed and demonstrated on a simulated and experimental setup of a six-DOF spatial CDPR.

Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large translational workspace and high dynamic performances. The rigid base frame of the CDPR is connected in parallel to the moving platform using cables. However, their orientation workspace is usually limited due to cable/cable and cable/moving platform collisions. This paper deals with the design, modelling and prototyping of a hybrid robot. This robot, which is composed of a CDPR mounted in series with a Parallel Spherical Wrist (PSW), has both a large translational workspace and an unlimited orientation workspace. It should be noted that the six degrees of freedom (DOF) motions of the moving platform of the CDPR, namely, the base of the PSW, and the three-DOF motion of the PSW are actuated by means of eight actuators fixed to the base. As a consequence, the overall system is underactuated and its total mass and inertia in motion is reduced.

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Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large translational workspace and high dynamics performances. Their rotational workspace is generally far more limited, however, which can be resolved by using cable loops, as was shown in previous research. In the case of fully-constrained CDPRs, cable loops can induce unwanted torques on the moving-platform, causing it to tilt and move away from its intended position, which we call parasitic tilt. Hence, the orientation accuracy of such robots is usually limited. This paper deals with the design, modelling and prototyping of a planar CDPR with infinite rotations, without parasitic tilt and without an additional motor. This robot, which we call a Cable-Driven Parallel Crane (CDPC), is composed of a mobile platform (MP) with an embedded mechanism and a transmission module. The MP is linked with the frame by a parallelogram of three cables to constrain its orientation, including a cable loop, as well as a fourth cable. The two-degree-of-freedom (dof) motions of the moving-platform of the CDPC and the internal dof of its embedded mechanism are actuated by a total of three actuators, which are fixed to the frame. As a consequence, the overall system is fully-actuated, its total mass and inertia in motion is reduced and it is free of parasitic tilts.

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Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large translational workspace and high dynamic performances. The rigid base frame of the CDPR is connected in parallel to the moving platform using cables. However, their orientation workspace is usually limited due to cable/cable and cable/moving platform collisions. This paper deals with the design, modelling and prototyping of a hybrid robot. This robot, which is composed of a CDPR mounted in series with a Parallel Spherical Wrist (PSW), has both a large translational workspace and an unlimited orientation workspace. It should be noted that the six degrees of freedom (DOF) motions of the moving platform of the CDPR, namely, the base of the PSW, and the three-DOF motion of the PSW are actuated by means of eight actuators fixed to the base. As a consequence, the overall system is underactuated and its total mass and inertia in motion is reduced.