Operating method of three-dimensional positioning device using moving characteristics of human arm

Abstract

When three-dimensional positioning devices such as a robot arm are operated, it is desirable for the devices to be operated by humans without the need for prior practice. The operating method in which the operator moves his/her arm and the device performs the same motion is a possible method. However, a difference may exist between the intended arm motion of the operator and the actual motion. In such a case, the positioning device performs the unintended than the intended motion of the operator. Therefore, in this study, the difference between the intended arm motion of the operator and the actual motion was investigated experimentally, supposing that the operator operates the device by his/her arm motion. The experimental results revealed that the operator tends to move the wrist joint center along a curve even though he/she intends to move it linearly. As an example, if the operator intends to move the wrist position straight in the right and left directions or the up and down directions, the actual wrist position tends to move along a curved path convex to the far direction. By considering the observed difference between the intended arm motion and the actual motion, an operating method was established. This method uses conversion equations to calculate the intended arm motion of the operator from the measured data of actual arm motion. In another experiment, operations using the new conversion equations and the conventional operation method were carried out. The results were compared and the effectiveness of the proposed method was confirmed.