Research Project

RobCab: Control strategies for cable-driven robot for low-gravity simulation


National Project

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Project Description

In the past few years, cable-driven parallel mechanisms have been increasingly studied since they are low-cost, light-weight robots that have all the required physical features in industry regarding the load capacity or the workspace size. Up to now, in most applications involving cable-driven robots, the platform moves the load freely in open space at high speeds and without any force feedback. However, a fully autonomous and safe cable-driven robot must be able to properly react to the contacts between the load and the environment. Thus, the objective of this project is to design and build a force-controlled cable-driven robot and to use it to simulate low gravity conditions, such as those of the underwater environments. The main scientific and technological contribution of this project will be within the frame of robots with force-position hybrid control. Despite their relevance, there are very few commercial robots with such hybrid controllers and, the one proposed herein will be the first cable-driven robot with such type of control.

Beside the simulation of low gravity conditions, such novel devices would easily find applications in many areas. The easy transportation of heavy loads is a demanding necessity in civil infrastructure services, disaster management, automated warehouses, and manufacturing companies, just to name a few. Moreover, a low-gravity simulation such as the one proposed in this project, can be used, or instance, in the rehabilitation of lower limb injuries, where the robot movements and the interaction forces with the environment should be soften.

The project addresses the design of a cable-driven robot, its physical construction, and the development of all the modeling and control tools necessary to properly simulate and command it.

Project Publications

Journal Publications

  • J.M. Porta and F. Thomas. Closed-form position analysis of variable geometry trusses. Mechanism and Machine Theory, 109: 14-21, 2017.

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  • A. Perez and F. Thomas. On Cayley's factorization of 4D rotations and applications. Advances in Applied Clifford Algebras, 2017, to appear.

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  • J.M. Porta, A. Rull and F. Thomas. Sensor localization from distance and orientation constraints. Sensors, 16(7): 1096, 2016.

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  • F. Moreno-Noguer and J.M. Porta. A Bayesian approach to simultaneously recover camera pose and non-rigid shape from monocular images. Image and Vision Computing, 52: 141-153, 2016.

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  • J.M. Porta and S. Hernández. Path planning for active tensegrity structures. International Journal of Solids and Structures, 78: 47-56, 2016.

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  • G. Alexandre, J. Cristophe, V. Ruiz de Angulo and C. Torras. Variable symmetry breaking in numerical constraint problems. Artificial Intelligence, 229: 105-125, 2015.

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Conference Publications

  • A. Rull, J.M. Porta and F. Thomas. Distance bound smoothing under orientation constraints, 2015 IEEE International Conference on Robotics and Automation, 2015, Seattle, pp. 1431-1436.

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Other Publications

  • O. Bohigas, M. Manubens and L. Ros. Singularities of Robot Mechanisms: Numerical Computation and Avoidance Path Planning. Volume 41 of Mechanisms and Machine Science. Springer, 2017.

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