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Certain telerobotic applications, including telerobotics in space, pose particularly demanding challenges to both technology and humans. Traditional bilateral telemanipulation approaches often cannot be used in such applications due to technical and physical limitations such as long and varying delays, packet loss, and limited bandwidth, as well as high reliability, precision, and task duration requirements. In order to close this gap, we research model-augmented haptic telemanipulation (MATM) that uses two kinds of models: a remote model that enables shared autonomous functionality of the teleoperated robot, and a local model that aims to generate assistive augmented haptic feedback for the human operator. Several technological methods that form the backbone of the MATM approach have already been successfully demonstrated in accomplished telerobotic space missions. On this basis, we have applied our approach in more recent research to applications in the fields of orbital robotics, telesurgery, caregiving, and telenavigation. In the course of this work, we have advanced specific aspects of the approach that were of particular importance for each respective application, especially shared autonomy, and haptic augmentation. This overview paper discusses the MATM approach in detail, presents the latest research results of the various technologies encompassed within this approach, provides a retrospective of DLR's telerobotic space missions, demonstrates the broad application potential of MATM based on the aforementioned use cases, and outlines lessons learned and open challenges.

This paper presents a new method to calculate and display an approximated workspace of a surgical robot in nearly realtime. Displaying this information on a screen in the operation room could support the surgeon during intraoperative trocar placement for teleoperated minimally invasive robotic surgery (MIRS). We give a short overview on existing trocar placement procedures in teleoperated MIRS and describe the possibilities and limitations of workspace analysis methods to support the surgeon during trocar placement. Our new method uses MIRS-specific simplifications to reduce the search space and enable the creation of a reduced workspace map. It was implemented for the DLR MiroSurge system. The implementation can create a reduced workspace map and display a mesh representation of the map in less than 2 seconds. We give a short outlook on how this method could be embedded in trocar placement procedures in the operation theater and what our future plans are with this method.

This paper outlines the development of the ROboMObil, an innovative electro-mobility concept based on intelligent central control of four Wheel Robots, which integrate the drivetrain, brakes, steering and dampers. The motivation behind the Wheel Robot concept, the implementation details together with the suspension design are described. The electric power system, consisting of a Li-Ion battery cluster to provide high-voltage power for propulsion and a low-voltage supply for vehicle control, is also discussed. Finally, we provide an overview of the Shared Autonomy control architecture and an outlook on the future research projects based on this demonstrator platform.

An elementary prerequisite for haptic applications is to preserve stability. Numerous studies have been presented in the past dealing with ensuring stability for haptic interfaces. The passivity condition of Colgate et al. (1994; 1997) represents one of the most cited theoretical studies towards a common stability condition. Although ensuring passivity of haptic devices is a general approach, it has the disadvantages of being conservative in terms of stability.

Autonomous service robots have to recognize and interpret their environment to be able to interact with it. This paper will focus on service tasks such as serving a glass of water where a humanoid two-arm-system has to acquire an object from the scene. A task planner should be able to autonomously discern the necessary actions to solve the task. In the process, a path planner can be used to compute motion sequences to execute these actions. To plan trajectories, the path planner requires a pair of configurations, the start and the goal configuration of the robot, to be provided e.g. by a task planner. This paper proposes a method to autonomously find the goal configurations necessary to acquire objects from the scene and thus makes an attempt to bridge the gap between task planning and path planning. The method determines where to grasp an object by analyzing the scene and the influence of obstacles on the intended grasp location. For the case where the goal object can not be grasped due to obstructing obstacles, a solution is proposed.

In this paper the Cartesian compliance control of a manipulator mounted on a flexible base is considered. The proposed control law aims at achieving a desired stiffness and damping in Cartesian coordinates while taking account of the base flexibility. The controller does not use any measurement of the base motion, however a model of the base stiffness is required. For the closed loop system, asymptotic stability in case of free motion is proven. Furthermore, considering interaction tasks, it is shown that the controlled manipulator system has a useful passivity property.

This paper analyses the Time Domain Passivity Control approach in the time-delayed telepresence context, and proposes a method which provides stable operation. The passivity controller for the two-port network which is created by the bilateral control and communication elements in [1] is shown to be not valid if a time delay is introduced in the communication channel. Classical stability analysis for the delayed system is presented and used as argument and benchmark for the proposed solution. Simulations and experimental results are discussed and compared with classical stability analysis.

Holding an object and manipulating it in 6D is a key application for multifingered robot hands. In the past many algorithms were proposed based on a weighted pseudoinverse of the grasp map combined with an internal force control. The majority of these algorithms require robust contact detection/tracking and switching controllers. Employing the virtual object introduced by Stramigioli we present an object-level control law. We define a novel virtual object frame based on the robot hand configuration. Our control law takes a desired object frame and desired grasping forces as input, it is passive, has an intuitive physical meaning, and stability is even given in case a finger looses contact with the object. A damping design as a function of the desired object stiffness and the combined hand-object inertia is presented. The performance of the controller is proven in two experiments implemented on the DLR Hand II.

Mechatronic systems are reaching a new level of complexity, both for the single component and for overall systems making necessary a new software concept for the development and usage of such systems. Here we introduce the agile Robot Development (aRD) concept, which is a flexible, pragmatic and distributed software design to support and simplify the development of complex mechatronic and robotic systems. It gives easy access to scalable computing performance (even in hard real-time) and is motivated by the abstract view on a robotic system as being a decentral net of calculation blocks and communication links. We discuss design considerations and an implementation of this concept and demonstrate its performance with first applications.