On the Design of a Three-DOF Cable-Suspended Parallel Robot Based on a Parallelogram Arrangement of the Cables

Dynamically feasible motions of a class of purely-translational cable-suspended parallel robots

“…It can then be seen that Ω ik coincides with the singularity plane Π ≡ Σ. For a robot such as the one in [30], then, there can be no cable interference unless the robot is at a singular configuration. This makes such an architecture attractive as the singularity-free and the interference-free workspaces coincide and very simple to visualize: therefore, this architecture was used for our tests (see Section 7).…”

“…Due to the equivalence between this robot (with a finite-extension EE) and a 3-cable robot with a point-mass EE, we can immediately see that τ tot 0 defines a vertical triangular prism having its upper vertices in A * 12 , A * 34 and A * 56 [35]. A particular design of the special architecture described in this section was proposed in [30]: in the latter article, P lies in the middle of the three segments B 1 B 2 , B 3 B 4 , and B 5 B 6 , so that α ij = −1 and…”

“…5. An example of such a robot is found in [30], where the authors show a design where all points A i 's are on the same horizontal plane Π, and all points B i 's are on the horizontal plane through P . Notice that, in the more general architecture illustrated in Fig.…”

“…In the current contribution, we consider a general spatial robot with a finite-size EE suspended by six cables that define three parallelograms, so that the EE orientation remains constant as the robot moves. The CSPRs presented in [15,20,30] can be seen as special cases of the general architecture studied here. Since cables have pairwise identical lengths, this architecture allows the robot to be controlled by three actuators, thus simplifying design and reducing cost.…”

Design of a Planar Cable-Driven Parallel Robot for Non-Contact Tasks

“…For the Pickable robot, undesired phenomena, such as friction, are significantly reduced by using air bearings, whereas, for the cleaning robot, friction is part of the process itself. A different approach for constraining the EE motion consists in adopting special cable configurations, such as the parallelogram arrangements inspired by delta robots [20][21][22]. This expedient allows obtaining a translational motion of the EE without any external constraint, provided that all cables are taut.…”