Modeling of Tension Control System with Passive Dancer Roll for Automated Fiber Placement

Abstract

The fiber tension should be kept constant during the automated placement of fiber prepreg. The velocity of the fiber placement end-effector moving on complex aircraft panel mould surface varies rapidly, which greatly disturbs the precision of tension control. This paper proposes a tension control strategy combining active control and passive control. The pay-off motor controls the fiber tension directly and a passive dancer roll is designed theoretically as the equipment for attenuation of tension disturbance to realize the real-time compensation of low-frequency velocity variations. The nonlinear model of tension control system, which includes the dynamics of the passive dancer roll, is established, and the effect of dancer roll parameters on its disturbances attenuation performance is analyzed. The controller is designed using the H∞ mixed sensitivity method. An experimental tension control precision about 2% is obtained at stable placement speed on the automated fiber placement (AFP) machine. The experiments also indicated that the tension would not vary over 1 N at a maximum acceleration of 4 m/s2.

Prediction of Cable Behavior Using Finite Element Analysis Results for Flexible Cables

“…The MCU for speed measurement operated at 1000 Hz, and the MCU for motor control operated at 500 Hz, so it was possible to operate quickly and accurately. Figure 6 shows that, to maintain a constant tension while winding the flexible cable around the cylinder, a weight was attached to the end of the cable, and a load cell was attached to the cable transfer device to measure the initial tension and tension during the experiment [ 15 , 16 ]. In addition, the design allowed the cable to move smoothly using pulleys to minimize friction while the cable was wound around the cylinder.…”

Additive Manufacturing of Large Coreless Filament Wound Composite Elements for Building Construction

“…1b :4a). a passive tension-control mechanism (mechanical dancer-bar 53 with a 1.2-m stroke) housed above the CF fiber creel, consisting of six pulleys and adjustable counterbalance weight ( Fig. 1b :4b).…”

Modeling of Precise Tension with Passive Dancers for Automated Fiber Placement

“…Secondly, repeated tension fluctuations increase the probability of wire blocking, which can lead to placement failure. A stable tension can reduce laying defects and the likelihood of laying failures, thus enhancing the quality of the laying [7,[14][15][16][17].…”