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An ISO10218-compliant adaptive damping controller for safe physical human-robot interaction

In human-robot interaction, the robot must behave safely, especially when an operator is present in its workspace. Even higher safety levels must be attained when physical contact occurs between the two. To this end, standards such as the ISO10218 define the requirements for a robot to be considered safe for interaction with human operators in an industrial environment. In this paper, we propose an adaptive damping controller that fulfills the ISO10218 requirements by limiting the tool velocity, power and contact force online (and only when needed). The controller is experimentally validated on a hand-arm robotic system, in a mock-up collaborative application. For the hand, safe interaction is enhanced by using tactile sensing, both to regulate grasp forces and to provide an intuitive interface for the operator.

A predictive control approach and interactive GUI to enhance distal environment rendering during robotized tele-echography: Interactive platform for robotized telechography

Performing a robotized telemedicine act via specific networks brings forth two issues. One is transparency in order to enable the operator, e.g. the medical ultrasound specialist, to safely and accurately perform bilateral tele-operation tasks despite the long time delays inherent to the communication link. To counter these effects, two strategies are combined to improve, at the operator site, the rendering of the interactions between the remote robotic systems with its environment (i.e. the patient), and the control of the robots orientation. The first approach is the development of a new control architecture based on an internal model providing an anticipated value of the distant environment stiffness; it is complemented with a graphic user interface (GUI) which provides the expert with the real-time relative position of the haptic probe with the robots end effector for a better tele-operated control. These combined strategies provide the expert with an improved interactive tool for a tele-diagnosis.

A mechatronic tele-operated system for echography using visual navigation assistance and a model based bilateral predictive control

This paper presents a tele-operated medical robotic system to perform tele-echography at a distance for the benefit of sites with reduced medical facilities. When performing the tele-echography act, medical experts require feedback information from the remote slave side. In this case, both image and force information is needed to render the distant environment of the robot. To efficiently control the remote system, the medical specialist analyses in almost real time ultrasound image extracted characteristics using fuzzy and fractal approaches; with the benefit of force feedback and appropriate predictive control proposed here to negotiate intrinsic communication time delays, the expert is able to accurately position the distant end-effector holding a real ultrasound probe to the desired searched organ for a quality ultrasound slice.

An Anticipative Control Approach and Interactive GUI to Enhance the Rendering of the Distal Robot Interaction with its Environment during Robotized Tele-Echography: Interactive Platform for Robotized Tele-Echography

Performing a robotized telemedicine act via specific networks brings forth the issue of transparency in order to enable the operator, e.g. the medical ultrasound specialist, to safely and accurately perform bilateral tele-operation tasks despite the long time delays inherent to the communication link. To counter these effects, two strategies are combined to improve, at the operator site, the rendering of the interactions between the remote robotic systems with its environment i.e. the patient, and the control of the robots orientation at the operator site. The first approach is the development of a new control architecture based on an internal model providing an anticipated value of the distant environment stiffness; it is complemented with a graphic user interface GUI which provides the expert with the real-time relative position of the haptic probe with the robots end effector for better tele-operated control. These combined strategies provide the expert with an improved interactive tool for tele-diagnosis.

MARTE PROJECT : TELE-ECHOGRAPHY BETWEEN KYPEROUNTA AND NICOSIA (CYPRUS)

Ultrasound experts, who are few and not always on hand when needed, have now the tool and the possibility to examine patients from a distance, and thus perform a complete diagnosis without being in the same geographical position with the patient. This is possible thanks to a telemedicine system aiming to provide the possibility to examine a remote patient using a tele-operated controlled robot. In the frame of this project, different validations have been performed to show the technical performances of the teleoperated chain and the repercussions on the clinical aspect. The clinical validation is the crucial part for the validation of the overall concept of tele-echography. Thus, various specialities were investigated all throughout the project life, with the participation of different medical experts from several countries, namely France, Spain and Cyprus.

Singularity avoidance in a robotized ultrasound scan

In a robotized ultrasound scanning system and more generally in any system which interacts with a human, the used control laws have to satisfy a safety of operating and functioning. Moreover these control laws have to guarantee a high precision in the medical gesture tracking, and especially within the framework of the ultrasound scanning, they assure the preservation of the ultrasound plane. The mechanical architecture of the designed robot takes into account the specifications of the medical application of the remote ultrasound scan. This robot presents singular configurations on its work space. These configurations perturb the follow-up of the medical remote gesture and lead to a loss of precision which induce errors in the follow-up of trajectory as well as in the ultrasonic plan. To solve this problem we set up specific control laws which take into account these singular configurations and allow to reproduce the movements generated by the medical expert with a great accuracy. The first part of this paper presents the geometric and kinematic modelling of the Protech robot used for the remote ultrasound and an analysis of its work space and its singular configurations. The second part describes the various approaches used for the management of these singular configurations. The third and last part presents the simulations of these approaches and the obtained results.

OpenPHRI: an open-source library for safe physical human-robot interaction

OpenPHRI is a C++/Python general-purpose software scheme with several built-in safety measures designed to ease robot programming for physical human?robot interaction (pHRI) and collaboration. Aside from providing common functionalities, the library can be easily customized and enhanced thanks to the projects open-source nature. The OpenPHRI framework consists of a two-layer damping controller, depicted in Figure 1. This allows the user to provide compliance and other safety features at both the joint and task levels, depending on the application.