Reconfigurable Integrated Multirobot Exploration System (RIMRES): Heterogeneous Modular Reconfigurable Robots for Space Exploration

Abstract

This paper presents the multirobot team RIMRES (Reconfigurable Integrated Multirobot Exploration System), which is comprised of a wheeled rover, a legged scout, and several immobile payload items. The heterogeneous systems are employed to demonstrate the feasibility of reconfigurable and modular systems for lunar polar crater exploration missions. All systems have been designed with a common electromechanical interface, allowing to tightly interconnect all these systems to a single system and also to form new electromechanical units. With the different strengths of the respective subsystems, a robust and flexible overall multirobot system is built up to tackle the, to some extent, contradictory requirements for an exploration mission in a crater environment. In RIMRES, the capability for reconfiguration is explicitly taken into account in the design phase of the system, leading to a high degree of flexibility for restructuring the overall multirobot system. To enable the systems' capabilities, the same distributed control software architecture is applied to rover, scout, and payload items, allowing for semiautonomous cooperative actions as well as full manual control by a mission operator. For validation purposes, the authors present the results of two critical parts of the aspired mission, the deployment of a payload and the autonomous docking procedure between the legged scout robot and the wheeled rover. This allows us to illustrate the feasibility of complex, cooperative, and autonomous reconfiguration maneuvers with the developed reconfigurable team of robots.

Design and field testing of a rover with an actively articulated suspension system in a Mars analog terrain

“…Figure shows SherpaTT during a multirobot system test. Details on the modularity and the multirobot scenario can be found in Roehr, Cordes, and Kirchner (), Sonsalla et al (, ), Wenzel, Cordes, and Kirchner ().…”

“…SherpaTT is the successor of the system Sherpa (Cordes, Dettmann, & Kirchner, ) improving the workspace of the legs while having a reduced number of active DoF (Cordes et al, ). Both Sherpa‐versions are designed to work together with other robots in unstructured terrain; while Sherpa has to transport a highly mobile six‐legged walking robot (Roehr et al, ), SherpaTT has to transport immobile payloads requiring higher flexibility in the rover’s body pose control for deployment and pick‐up. Compared with the design of the predecessor Sherpa, SherpaTT’s suspension provides a three‐ instead of two‐dimensional positioning of the LEP by introducing a second parallelogram in the leg and thus creating a “knee.”…”

“…If a wheel breaks through a crust and gets stuck in soft soil, the wheel can be lifted and placed in a different location. If required, the manipulation arm can add stability during the repositioning of the wheel, Roehr et al (). Alternatively, the footprint can be changed for stable tripod‐stance if the arm support is not feasible.…”

“…Figure 2 shows SherpaTT during a multirobot system test. Details on the modularity and the multirobot scenario can be found in Roehr, Cordes, and Kirchner (2014), Sonsalla et al (2014Sonsalla et al ( , 2017, Wenzel, Cordes, and Kirchner (2015). SherpaTT is the successor of the system Sherpa (Cordes, Dettmann, & Kirchner, 2011) improving the workspace of the legs while having a reduced number of active DoF .…”

“…Both Sherpa-versions are designed to work together with other robots in unstructured terrain; while Sherpa has to transport a highly mobile six-legged walking robot (Roehr et al, 2014) Combining all three joints creates the toroid shown in Figure 5a Combining the motion range of the three DoF Pan, InnerLeg, and…”