Differential game theory for versatile physical human-robot interaction

The last decades have seen a surge of robots working in contact with humans. However, until now these contact robots have made little use of the opportunities offered by physical interaction and lack a systematic methodology to produce versatile behaviours. Here, we develop an interactive robot controller able to understand the control strategy of the human user and react optimally to their movements. We demonstrate that combining an observer with a differential game theory controller can induce a stable interaction between the two partners, precisely identify each other’s control law, and allow them to successfully perform the task with minimum effort. Simulations and experiments with human subjects demonstrate these properties and illustrate how this controller can induce different representative interaction strategies

The Role of Roles: Physical Cooperation between Humans and Robots

Since the strict separation of working spaces of humans and robots has experienced a softening due to recent robotics research achievements, close interaction of humans and robots comes rapidly into reach. In this context, physical human–robot interaction raises a number of questions regarding a desired intuitive robot behavior. The continuous bilateral information and energy exchange requires an appropriate continuous robot feedback. Investigating a cooperative manipulation task, the desired behavior is a combination of an urge to fulfill the task, a smooth instant reactive behavior to human force inputs and an assignment of the task effort to the cooperating agents. In this paper, a formal analysis of human–robot cooperative load transport is presented. Three different possibilities for the assignment of task effort are proposed. Two proposed dynamic role exchange mechanisms adjust the robot’s urge to complete the task based on the human feedback. For comparison, a static role allocation strategy not relying on the human agreement feedback is investigated as well. All three role allocation mechanisms are evaluated in a user study that involves large-scale kinesthetic interaction and full-body human motion. Results show tradeoffs between subjective and objective performance measures stating a clear objective advantage of the proposed dynamic role allocation scheme

40 GHz InP-based photoreceiver OEICs: Application for 40 Gb/s TDM systems and beyond

Progress of 40 Gb/s photoreceiver OEICs for 1.55 mu m TDM systems is described. The OEICs comprise side-illuminated photodiodes and amplifiers, based on the traveling wave concept. Results from packaged OEICs into pig-tailed modules are given

37 GHz bandwidth InP-based photoreceiver OEIC suitable for data rates up to 50 Gb/s

A photoreceiver optoelectronic integrated circuit based on InP with a bandwidth of 37 GHz is presented. The receiver consists of a 50 GHz waveguide-integrated photodiode and a distributed amplifier with a bandwidth of 39.5 GHz, which is composed of four high-electron mobility transistors. A system experiment at 40 Gb/s receiving an return-to-zero coded optical input signal is demonstrated, and a good quality of eye pattern is achieved

A hybrid human motion prediction approach for human-robot collaboration

Prediction of human motion is useful for a robot to collaborate with a human partner. In this paper, we propose a hybrid approach for the robot to predict the human partner’s motion by using proprioceptive and haptic information. First, a computational model is established to describe the change of the human partner’s motion, which is fitted by using the historical human motion data. The output of this model is used as the robot’s reference position in an impedance control model. Then, this reference position is modified by minimizing the interaction force between the human and robot, which indicates the discrepancy between the predicted motion and real one. The combination of the prediction using a computational model and modification using the haptic feedback enables the robot to actively collaborate with the human partner. Simulation results show that the proposed hybrid approach outperforms impedance control, model-based prediction only and haptic feedback only

27 GHz Bandwidth Integrated Photoreceiver Comprising a Waveguide Fed Photodiode and a GaInAs/AlInAs-HEMT based Travelling Wave Amplifier

Optical front-ends are considered to play a major role in future communication systems operating at bit rates of 20 or even 40 Gbit/s, as well as in mobile communication systems with fibre-optic distribution networks. Consequently, different approaches for the monolithic integration of high-speed receivers for a wavelength of 1.55 /spl mu/m can be found in the literature. In this paper, we report on the first monolithical integration of an optical receiver OEIC, which combines the advantageous high-speed characteristics of the waveguide integrated pin photodiode and of the travelling wave amplifier (TWA) circuit, both based on the InP material system