The DLR lightweight robot: design and control concepts for robots in human environments

Abstract

The paper presents a new generation of torque-controlled lightweight robots (LWR) developed at the Institute of Robotics and Mechatronics of the German Aerospace Center. In order to act in unstructured environments and interact with humans, the robots have design features and control/software functionalities which distinguish them from classical robots, such as: load-to-weight ratio of 1:1, torque sensing in the joints, active vibration damping, sensitive collision detection, as well as compliant control on joint and Cartesian level. Due to the partially unknown properties of the environment, robustness of planning and control with respect to environmental variations is crucial. After briefly describing the main hardware features, the paper focuses on showing how joint torque sensing (as a main feature of the robot) is consequently used for achieving the above mentioned performance, safety, and robustness properties.

Continuous robot control using surface electromyography of atrophic muscles

“…The work presented here serves as a groundwork to this goal. To validate the feasibility of the approach, we tested the EMGcontrol interface on a full dynamics simulation of the DLR Light-Weight Robot III (LWRIII) [20], [21] in combination with the DLR 5-finger robotic hand [22]. Combined with its soft-robotics control schemes, the LWR [23], [24] has shown its applicability to safe human robot interaction [25] and as an assistive robotic device in multiple scenarios [6].…”

A tool for the evaluation of human lower arm injury: approach, experimental validation and application to safe robotics

“…20,21 In Eq. (8), F is the normal impact force applied to the lower arm; x 0 and x 1 denote the displacement between the robot end-effector and the lower arm bone tissue at impact start time t 0 and end time t 1 . A EE is the average contact surface area between the robot end-effector and the lower arm surface.…”

“…Nevertheless, presumably even a greater deal of work will be accomplished by robots soon, as novel manipulators capable of safe and sensitive manipulation and interaction capabilities have entered the market. [1][2][3] On the market side, the expectation regarding these novel interactive robotic devices is to revolutionize manufacturing as we know it today and, in particular, let people and robots work closely together. Designing robots for interaction has become a challenging subdomain in pHRI (physical human-robot interaction), leading to novel devices that have one thing in common: active and/or passive compliance together with lightweight mechanical design as central paradigms.…”

“…Soft-tissue injuries occur at an IED greater than 2.52 J/cm 2 , 21 while hematoma or suffusions may occur below this value. 1 We make following concrete contributions to lower arm injury analysis in this paper.…”

“…One very successful early example is the fully torque-controlled DLR/KUKA Lightweight robot family. 1 The robots are equipped with joint torque sensors in each joint and have redundant position measurement (on the motor and link side). 4 Their underlying control paradigm is the so-called "soft-robotics" concept, aiming at equipping the robot with high performance interaction control capabilities, such as impedance control and collision detection with reflex reaction.…”