Development and design support through human and life engineering (razor for hand use)

It is possible to evaluate and propose what materials, shapes, and structures would make it easy to use (such as easy to shave and with fewer missed spots).

**Evaluation by Human and Life Engineering** Participants will use various types of razors to shave specified areas of facial hair using either a designated method or their usual technique. They will report their feelings during the process, and we will measure the muscle strain involved while observing hand movements. The evaluation will be conducted with facial hair present as much as possible. ■ Evaluation Targets: Shape and material of the head and handle, weight, and the movable mechanism of the head, etc. ■ Evaluation Areas: Face (forehead, cheeks, under the nose, chin, upper arm, inner and outer forearm, armpit, legs). Please refer to the attached materials for instructions on how to use the razor. ■ Evaluation Items: (1) Subjective Evaluation: - Overall ease of use - Shaving comfort - Ease of determining the angle between the blade and skin - Ease of maintaining the angle between the blade and skin - Presence of missed spots - Blade and skin compatibility - Discomfort (2) Behavioral and Physiological Evaluation: - Muscle strain on hands and arms - Hand movements relative to the skin - Grip of the razor **Expected Outcomes** Insights will be gained regarding the following items: ■ Which subjective evaluation criteria strongly influence overall ease of use ■ Which muscle strains are most closely related to ease of use, and which hand or finger movements are strongly related ■ What specifications of the razor will enhance ease of use

Contract measurement