Kinematic and force synergies can be used to reduce the complexity and dimensionality of the motion generation and control problem, as well as facilitate the mechanical implementation of robotic hands. In this paper we present a novel implementation of hardware synergies realized on the actuation level by leveraging a novel reconfigurable electric actuation topology principle. The proposed electric actuation topology enables different actuation synergies by changing the interconnections among the actuators at the electrical/motor driver level. We describe the synergies and their implementation in a port-based context, and elaborate how equivalent hard and soft synergies emerge from the electric power flow within different actuation topologies. We realize the reconfigurable electric actuation topology scheme in the HERI III hand, a novel robust and powerful robotic gripper, also introduced in this paper, resulting in easy to control behaviours like on industrial grippers or underactuated hands, but with the high grasping versatility of fully actuated hands. Finally we present grasping experiments performed on the HERI III hand that clearly show the desired behaviours and validate the innovative proposed scheme.

Linear Series Elastic Actuators exhibit a restricted design space. This inevitably leads to design trade-offs translating into robot performance limitations. These prevent robots from eventually reaching human comparable soft but also powerful physical interaction performance.This work presents a novel fixed passive rolling flexure design principle enabling the realization of a wide range of progressive torque-deflection characteristics. The proposed principle displays low hysteresis and can be manufactured in single 2D components. The paper derives the analytic foundation for the rolling flexure principle and is supported by numerical finite element analysis. The theory is validated by experimental results obtained on two laboratory prototypes.

This paper presents the autonomous battery exchange operation for small scale UAVs, using a mobile ground base that carries a robotic arm and a service station containing the battery exchange mechanism. The goal of this work is to demonstrate the means to increase the autonomy and persistence of robotic systems without requiring human intervention. The design and control of the system and its components are presented in detail, as well as the collaborative software framework used to plan and execute complex missions. Finally, the results of autonomous outdoor experiments are presented, in which the ground rover successfully localizes, retrieves, services, and deploys the landed UAV, proving its capacity to extend and enhance autonomous operations.

This paper presents the mechatronic design of a robotic arm that is mounted on a ground rover and used to deploy and recover small-scale unmanned aerial vehicles. The arm and rover are part of a network of collaborative robotic agents aiming to enhance current rescue operations by supporting human operators without burdening them with servicing tasks. The robust autonomy of the system, guaranteed in part through the addition of this robotic arm, is a main contributing factor. Design requirements are derived from the context of the rescue mission and a kinematic analysis is provided that leads to a customized design, including variable stiffness joints for compliant interaction with the environment. Experiments demonstrate the system's ability to perform the required Cartesian trajectory control and manipulation tasks, and to achieve a desired variable end-effector compliance.

The increasing use of Variable Stiffness Actuators (VSAs) in robotic joints is helping robots to meet the demands of human-robot interaction, requiring high safety and adaptability. The key feature of a VSA is the ability to exploit internal elastic elements to obtain a variable output stiffness. These allow the joints to store mechanical energy supplied through interaction with the environment and make the system more robust, efficient, and safe. This paper discusses the design of leaf springs for a sub-class of VSAs that use variable lever arm ratios as means to change their output stiffness. Given the trade-off between compactness and the maximum energy storage capacity, the internal springs' dimensions and material choice are assessed through a theoretical analysis and practical experiments.

The detection of two-dimensional optical signals which have been corrupted by noise is considered. Discussion is limited to the detection of a known object in a known location. The problem is approached from the classical statistical technique of hypothesis testing. Initially the solution is formulated in very general terms. The decision rule is derived for a signal distorted by noise of an unspecified type which may include signal dependent noise. Once the decision rule is obtained, the probabilities of false alarm and detection are evaluated from a{\sl a priori}knowledge of the noise and imaging system. The general results are applied to Poisson noise, signal dependent Gaussian noise, and binomial noise.