Haptic guidance improves the visuo-manual tracking of trajectories

BACKGROUND: Learning to perform new movements is usually achieved by following visual demonstrations. Haptic guidance by a force feedback device is a recent and original technology which provides additional proprioceptive cues during visuo-motor learning tasks. The effects of two types of haptic guidances-control in position (HGP) or in force (HGF)-on visuo-manual tracking ("following") of trajectories are still under debate. METHODOLOGY/PRINCIPALS FINDINGS: Three training techniques of haptic guidance (HGP, HGF or control condition, NHG, without haptic guidance) were evaluated in two experiments. Movements produced by adults were assessed in terms of shapes (dynamic time warping) and kinematics criteria (number of velocity peaks and mean velocity) before and after the training sessions. CONCLUSION/SIGNIFICANCE: These results show that the addition of haptic information, probably encoded in force coordinates, play a crucial role on the visuo-manual tracking of new trajectories

Analiza FPGA implementacije bilateralnih algoritama upravljanja za dodirnu teleoperaciju

This paper presents the FPGA implementation of sliding mode control algorithm for bilateral teleoperation, such that, the problem of haptic teleoperation is addressed. The presented study improves haptic fidelity by widening the control bandwidth. For wide control bandwidth, short control periods as well as short sampling periods are required that was achieved by the FPGA. The presented FPGA design methodology applies basic optimization methods in order to meet the required control period as well as the required hardware resource consumption. The circuit specification was performed by the high-level programing language LabVIEW using the fixed-point data type. Hence, short design times for producing the FPGA logic circuit can be achieved. The proposed FPGA-based bilateral teleoperation was validated by master-slave experimental device.Ovaj rad opisuje FPGA implementaciju algoritama upravljanja kliznim režimima za bilateralnu teleoperaciju, pri čemu je opisan problem haptičke teleoperacije. Prikazano istraživanje poboljšava dodirnu pouzdanost proširenjem upravljačkog propusnog pojasa. Za široki propusni pojas, potrebni su kratki upravljački periodi i brzo vrijeme uzorkovanja, što je postignuto primjenom FPGA sklopovlja. Prikazana metodologija za projektiranje FPGA sklopovlja koristi osnovne optimizacijske metode s ciljem postizanja potrebnih upravljačkih perioda i zahtijevane fizičke iskorištenosti sklopovlja. Specifikacije sklopovlja su provedene programskim jezikom visoke razine LabVIEW uz korištenje podataka s nepomičnim decimalnim zarezom. Stoga je moguće implementirati traženu logiku na FPGA sklopovlje u kratkom vremenu. Opisana bilateralna teleoperacija temeljena na FPGA slopovlju je testirana na eksperimentalnom postavu s nadre.enim i podre.enim čvorom

Stability analysis and robust control for fixed-scale teleoperation

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN032974 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Robust variable-scale bilateral control for micro teleoperation

This paper discusses variable-scale bilateral control for micro teleoperation. A method is proposed to synthesize robust variable-scale controllers that guarantee system stability and realize robust performance in contact with any arbitrary, but passive, operator and environment. The proposed method is based on the formulation as a robust output feedback constant scaled ℋ∞ problem. A variable scaled teleoperation system appears as a polytopic linear parameter-varying (LPV) plant, with an affine relation on the scale factors. Gain-scheduling is used to derive robust stable time-variant ℋ∞ controllers for online variable scaling. Improved controller performance is obtained through the introduction of an affine and scheduled-parameter-dependent weighting. The controller synthesis problem is formulated as a set of linear matrix inequalities (LMI's) augmented with a nonconvex rank condition. An efficient algorithm is constructed to synthesize a set of sub-optimal controllers over the parameter space. The validity of the proposed methods are confirmed experimentally. ©2008 IEEE.status: publishe