This paper introduces locomotion modes for the planetary rover Sherpa 1 . The rover's locomotion system consists of four wheeled-legs, each providing a total of six degrees of freedom. The design of the active suspension system allows a wide range of posture and drive modes for the rover. Selflocking gears in the suspension system allow to maintain the body height without the need of actively driving the actuators. Thus, energy-efficient wheeled locomotion and at the same time high flexibility in ground adaption and obstacle negotiation are possible, as well as high payload capabilities. Furthermore, the rover will be equipped with a manipulator arm explicitly designed to be used for locomotion support. Thus, all degrees of freedom of the system can be used to enhance the locomotive capabilities. This paper gives an overview of the mechanical design of the rover, kinematic considerations for movement constraints on the wheel contact points are presented. Based on these constraints, the wheel motions due to the commanded velocities of the platform can be calculated, taking into account the flexible posture of the rover. A first set of possible locomotion modes for the rover is presented in this paper as well.

The LUNARES (Lunar Crater Exploration Scenario) project emulates the retrieval of a scientific sample from within a permanently shadowed lunar crater by means of a heterogeneous robotic system. For the accomplished earth demonstration scenario, the Shakelton crater at the lunar south pole is taken as reference. In the areas of permanent darkness within this crater, samples of scientific interest are expected. For accomplishment of such kind of mission, an approach of a heterogeneous robotic team consisting of a wheeled rover, a legged scout as well as a robotic arm mounted on the landing unit was chosen. All robots act as a team to reach the mission goal. To prove the feasibility of the chosen approach, an artificial lunar crater environment has been established to test and demonstrate the capabilities of the robotic systems. Figure 1 depicts the systems in the artificial crater environment. For LUNARES, preexisting robots were used and modified were needed in order to integrate all subsystems into a common system control. A ground control station has been developed considering conditions of a real mission, requiring information of autonomous task execution and remote controlled operations to be displayed for human operators. The project successfully finished at the end of 2009. This paper reviews the achievements and lessons learned during the project.

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In this paper, the development of a docking device for a self-reconfigurable multi-module system with high heterogeneity is presented. The docking device, more precisely the electromechanical interface, is used to connect mobile and immobile units with each other in order to provide a reliable mechanical connection as well as to allow energy and data transfer. A gender-principle approach was chosen which allows docking in different positions. This paper focuses on the mechanical design and conducted experiments. Robustness against influence of particles in size 0,02 mm up to 1,3 mm was proven. Docking operations with loads of up to 600 N are possible. Three different contact probe types are evaluated to find an adequate tip for reliably contacting in dusty environments. The work presented in this paper is part of the RIMRES 1 [1] project.

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