Researchers are developing a computerized air jet weaving simulator and databases that address fiber and yarn motion dynamics during air jet weaving. Fiber optic sensors attached to a profiled reed measure yarn velocity. A Labview program converts signals produced by the filling yarn entering the sensor into time values and calculates the velocity form the time-distance relationship. Modifications to the system include increased drum feeder capacity to support high running speeds and minimize weft breakage, the use of two accumulators with high storage capacity, electronic control, and programmable filling yarn length and coil settings. Optocouplers on the Jet Control Unit connect the unit to the accumulators. Jet control software synchronizes the motion of the two accumulators.