Springback measurement in three roll push bending process of hollow structural sections

Three roll push bending is largely used to manufacture curved hollow structural sections. In this process, when new production batches are launched, long and repetitive trials-and-error procedures are necessary to compensate for the springback that may affect the final geometrical accuracy. Several off-line optimization techniques, both experimental and numerical, are available, but they require costly material characterizations and long computational times. The paper presents a new in-line approach based on inertial measurement techniques, which allows the accurate real-time measurement of the bent geometry during the process. The validation experiments are presented as well as the evaluation of the measurement accuracy. (C) 2017 Published by Elsevier Ltd on behalf of CIRP.