In-process nip point temperature estimation in automated tape placement based on analytical solution and remote thermal measurements

The optimisation and control of automated tape placement (ATP) requires fast analysis tools able to utilise process data for predictions and monitoring. In this study, a strategy for in-process estimation of nip point temperatures is proposed. The method is based on a combination of two one-dimensional analytical solutions of heat transfer in ATP using temperature data measured on the tool surface, combined with an inverse solution for the estimation of power delivered by the heating device on the composite surface. The performance of the method is examined against a validated finite element model. Approximations of nip point temperature show good correlation for different tool materials, with an average error of 15 degrees C and a maximum of 50 degrees C which is satisfactory for the processing of high-temperature thermoplastic materials. The analytical scheme offers real-time estimations of the nip point temperature with the potential to be used for process control of ATP.