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A method for studying the control of three-dimensional isometric forces using dynamic stereogram.

J T Massey·G W Hovey·W Schneider·J G Chubbuck·A P Georgopoulos
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Abstract

A system has been developed for measuring the three-dimensional (3D) isometric forces produced by the arm in response to a visual stimulus. The output of 3 load cells is combined to determine the components of the 3D response force. The maximum force range of the load cells is 2000 g which can be read with a resolution of 4 g and with a measured accuracy of +/- 10 g. An overload stop protects the device to a load of 23 kg. The visual instruction to the subject concerning the direction and magnitude of the 3D force vector to be produced is presented using a vivid spherical stereogram. This stereogram is produced using the anaglyphic technique where the left and right images are separated by color filters. A dense aggregation of points defines the target cursor, which can be positioned anywhere inside or on the surface of the sphere. This cursor can represent a stationary or a moving target. A force feedback cursor can be provided to indicate to the subject his/her response. The color display on the cathode ray tube is produced by a display generator driven by a computer.

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Amplifiers, ElectronicElectronic Data ProcessingElectronicsElectrophysiologyHumansIsometric ContractionMuscle ContractionPsychomotor PerformanceJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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J T Massey, G W Hovey, W Schneider, J G Chubbuck, A P Georgopoulos. 1988. A method for studying the control of three-dimensional isometric forces using dynamic stereogram.. https://doi.org/10.1016/0165-0270(88)90161-6

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