This paper considers a class of high-speed airjet weaving machines that is characterized by excessive harness frame vibration, resulting in premature failure. This problem is tackled through addition of an auxiliary, input torque balancing mechanism: A centrifugal pendulum, of which the pendulum motion is imposed by an internal cam. While earlier work by the same authors focused on the design, optimization, and robustness analysis of this mechanism, the current paper presents experimental results. The considered setup is an industrial weaving machine à blanc equipped with a centrifugal pendulum prototype. Below a critical speed, the prototype functions as predicted and significantly improves the machine dynamics: The drive speed fluctuation is reduced by a factor of 2.5 and the vibration level of the harness frames is halved. Above the critical speed, however, torsional resonance dominates the machine dynamics. This phenomenon is verified on simulation by extending the rigid-body setup model, on which the centrifugal pendulum design is based, with a torsional degree of freedom.

A trend towards thicker and larger sheet metal parts can be observed. This leads to the construction of huge press brakes. A method to reduce the bending force is to preheat locally and quickly the bending area of the thick steel plate. For this purpose a dynamic contact method has been chosen: the steel is heated by being put in contact with preheated 'contact elements'. This method was experimentally tested on low carbon steel plates with a prototype setup. Reported results of the tests include achievable temperature distributions, and associated bending force. An achievable press force reduction of over 50% was demonstrated. The proposed preheating process has been simulated using the Finite Element method. Referring to the measured temperature evolutions, an appropriate value for the heat transfer coefficient could be determined. This allowed simulating the process for other combinations of plate thickness and contact element size.