Parallel robots with configurable platforms: Fundamental aspects of a new class of robotic architectures

Abstract

This paper introduces general and fundamental aspects of a new class of parallel robots termed ''parallel robots with configurable platforms''. The concept behind parallel mechanisms with configurable platforms is that the rigid link (non-configurable) end-effector is replaced by an additional closed-loop chain (the configurable platform). Some of the links of this closed loop are attached to the limbs so both the position and the configuration of the platform can be fully controlled from the motors located on the base. They retain the advantages of classical parallel robots, i.e. that all the motors are grounded on the base, while offering mechanical grasping capabilities via multiple contact points. Despite the few studies that have been done yet on the subject, the possible range of applications for this type of architecture is promising since it would be suitable for any application requiring both controlled grasping capabilities and high dynamic performance. This paper provides some preliminary results regarding the topology, mobility, overconstraints, Jacobian matrix, singularities and type synthesis of parallel robots with configurable platforms.

Cable-Driven Parallel Robot with Reconfigurable End Effector Controlled with a Compliant Actuator

“…Using Graph Theory and Screw Theory [ 22 ], it is possible to represent, after simplification, this mechanism as that seen in Figure 4 .…”

“…These robots have a parallel structure and their end effector is a passive mechanism instead of a rigid body. In [ 22 ], Lambert et al described the fundamental aspects of parallel robots with a reconfigurable platform. In [ 23 ], a generalized analysis of this kind of robot was performed by using screws algebra considering the EE as a closed-loop chain.…”

Collision-free path planning of a novel reconfigurable mobile parallel mechanism

“…The outputs of Algorithm 3 are the x-y coordinates of the mobile robots. Lines 3-6 describe the parameters and variables defined in equations (3) and (4). In line 7, a for-loop is started with a condition on time steps.…”

“…3 It should be noted that some preliminary studies have been conducted regarding the kinematic modeling and analysis of the reconfigurable parallel mechanisms. [4][5][6] In this paper, kinematic analysis of a three-legged reconfigurable parallel mechanism, called the 'Taar Reconfigurable ParaMobile' (TRPM), is proposed.…”

Cinemática de un manipulador configurable por medio de la teoría de tornillos

“…Más todavía, gracias a los grados de libertad excedentes, el manipulador paralelo es capaz no sólo de ejecutar la tarea de salida original sino que también será capaz de eliminar o escapar de configuraciones singulares, incrementar el espacio de trabajo, mejorar la destreza y evasión de obstáculos, optimizar la transmisión de fuerza, entre otras limitaciones atribuidas a los manipuladores paralelos. Recientemente un concepto innovador designado como plataforma configurable se ha introducido en la ya exitosa trayectoria del estudio de los manipuladores paralelos con el objetivo de incrementar el potencial bien probado de los robots reconfigurables (Lambert and Herder, 2016;Hoevenaars et al, 2017;Kang and Dai, 2019;Gallardo-Alvarado and Tinajero-Campos, 2019). Con dicha plataforma configurable, además de las ventajas de generar manipuladores paralelos cinemáticamente redundantes (Yi et al, 2002;Mohamed and Gosselin, 2005) debido a la inclusión de grados adicionales de libertad acreditados a una cadena cinemática interna cerrada, esta nueva clase de robots admite la instalación de múltiples efectores finales (Hoevenaars et al, 2017) superando en creatividad y capacidad a los manipuladores convencionales equipados con plataformas rígidas.…”