Massage has both physical and mental benefits. Pressure massage is suitable for exerting a strong force on the skin’s surface in the normal direction. This technique is taught visually or using force feedback. Quantitative evaluation and learning methodologies are required. In this study, we propose a learning support system for massage techniques. The applied force and angle are quantitatively evaluated. Large forces, such as those applied during a massage, are difficult to measure using conventional rigid sensors or sensors incapable of handling large displacements. Therefore, we propose a flexible three-axis force sensor with an inflatable structure using pneumatics. The sensor is made of a non-elastic material; therefore, it can measure large forces based on volume changes. We show the design and construction of the proposed sensor and evaluate it.

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