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This study focuses on the real-time measurement of the distributed pinch force in minimally invasive surgery with a piezoresistive tactile sensor. The measurement of the pinch force in distributed form is important because the conventional surgical tools have angular opening/closing mechanism, which causes non-uniform force distribution on the contacting sample. Additionally, the location and the magnitude of the equivalent pinch force is calculated. The grasping of the samples with homogenous and constant pinch force and the characterization of the samples with low elastic modulus can be carried out with tactile sensor included surgery tools. Apprentice surgeons can benefit the advantages of the thin film sensors in their training.

This study investigates coefficient of friction of flat-tipped laparoscopic surgery tool (bowel grasper) in an ex vivo experiment in order to identify the approximate coefficient of friction between laparoscopic tool and the organic sample. The estimation of friction force is essential for ensuring safe grasping. The friction tribometer and the laparoscopic grasper setup were the two experimental setups to conclude the friction of the tool in the absence tactile sensor. The measurement of the pinch force and estimation of the friction force from the measured pinch force and the coefficient of friction is suitable for novice surgeon training.

Multi purpose hydraulic die spotting presses can be used for both die spotting and mass production. Due to the reducing cycle time of hydraulic presses in mass manufacturing, dynamic analysis can be used to determine the oscillations caused by the structural design of the hydraulic press. Oscillations are generated during loading and unloading cycle of press operation and can affect product quality, energy consumption, product life of press etc. Resonance which is related to natural frequency and damping ratio, must be avoided in order to increase the quality of press. There must be a necessary interval between operation (cycle) frequency and the natural frequency of the hydraulic press. Thus, the resonance can be prevented. In this work, the natural frequencies of the 2000 tone multi purpose hydraulic die spotting press is firstly calculated by modal analysis by using finite element model (FEM) and secondly measured during operation.