IN-SITU QUANTIFICATION OF MANUAL ASSEMBLY FORCES AND POSTURES DURING THE MANUFACTURE OF TV DEFLECTION COILS

A system is described which has been developed to meet an industrial r equirement for performing in-situ quantitative measurements of manual forces and postures applied by human assembly line operators. Virtual reality devices are shown to offer a valuable means of meeting the nec essary sensory requirements. The instrumentation is also seen to satis fy the requirements for a generic force and posture measurement system applicable to most human assembly operations in manufacture. A set of force transducers incorporated into a pair of Datacq(R) gloves togeth er with a force triggered image capturing facility, all controlled by a PC compatible, comprise the main hardware elements of the basic syst em. The instrument software provides on-line force and posture data ca pture facilities, which allows quality control staff to assess the way the operator undertakes the assembly process, including maximum force s applied and a measure of the effort or work done per assembly cycle. The full data recording may be reviewed, zoomed and edited using a pl ayback mode, allowing the observer a convenient way of assessing risk in undertaking an assembly operation since both the phalange forces an d the wrist posture for a particular assembly operation are measured q uantitatively. Results are presented for a representative electronics assembly task involving the assembly of TV deflection coils using oper ators employed by a U.K. manufacturer. The forces used by operators in this manufacturing procedure are related to current knowledge on reco mmended maximum forces a human should repeatedly apply before the occu rrence of muscle fatigue. (C) 1997 Elsevier Science Ltd. All rights re served.