Appropriate Operating Force of Knob in Certain Conditions

In the process of driving a car, people often use rotary knob to adjust the temperature of air-conditioning or music volume, etc. This operation is very frequent and necessary. As we all know, when we make changes on the knob, the height, angle, size and operating force of the knob will affect the comfort of the operation knob. Therefore, in order to improve use experience, it is necessary to study the comfortable operating force of knobs. This paper uses MARK-10 force measuring equipment (torque meter, measuring rotating moment), sets the test bench and sets up different knob heights (500 mm, 700 mm, 900 mm), angles (20°, 30°, 40°), sizes (16 mm, 27 mm, 36 mm), operating forces (1N, 3N, 7N) and other parameters range. Then invite 10 subjects to participate in the experiment, recording the subjective evaluation on the different operating force, finding that the subjective score of the 1N and 3N is higher. Based on this research result the appropriate knob operating force which is between 1N and 3N is concluded.