Object Manipulation of the Variable Topology Truss system
This work addresses the underexplored manipulation capability of truss robots, providing a control method for a novel robotic system.
The paper presents a hybrid control framework for object manipulation with the Variable Topology Truss (VTT) system, combining position and force control without explicit decoupling. Experiments demonstrate consistent and reliable manipulation, with quantitative assessment of combined tracking performance.
This paper presents an object manipulation strategy for the Variable Topology Truss (VTT) system, a truss robot that comprises actuated truss members connected by passive spherical joints. Although truss robots were originally proposed as rapidly deployable manipulators, manipulation strategy has not been studied thoroughly. To enable manipulation, we introduce a hybrid control framework that regulates position and force concurrently without explicit decoupling. At the actuator level, each member employs a sensor-based force feedback controller to generate the desired axial forces despite high actuator friction. At the task level, the forces applied at the end-effector nodes are produced by computing the required member forces using a static model of the VTT. We evaluate force-tracking performance through experiments on both a single member module and the full VTT system. Finally, we demonstrate object manipulation using two representative configurations and quantitatively assess combined position and force tracking performance. Experimental results confirm that the proposed approach enables consistent and reliable object manipulation with the VTT system.