Mandrel is actuated by an AC motor running at a
constant speed of 4.2 rpm. During the startup time, carriage’s motor is ramping up
slowly in order to ensure the motor is capable to reach the maximum speed without
slip. Another benefit of ramping up the motor is that the position of the carriage will
be known at all time. This is important to determine the number of steps required to
shift the fiber with respect to the initial winding for each winding passage. When
the carriage is moving along the lead screw, limit switch is used to check whether
the home position at the ends of the lead screw has been reached. Since winding
layer is updated only when the forward and backward passes have been completed,
the direction of winding (forward pass or backward pass) will be used to determine
whether a new winding layer has been completed. Since the winding is started with
a forward pass, the winding turns counter P is increment by one if another forward
pass has been completed. The direction of motion is determined by checking the
counter for winding passage. The whole process is repeated if it is detected that the
mandrel has not been wound completely. It is done by comparing the current
winding turns with the required number of winding turns which was determined at
the earlier stage of the program