| 摘要 |
The invention comprises an arrangement for controlling a machine by means of the body movement of the operator. It is used for controlling a sewing machine intended for a handicapped person or for an operator not using the foot control. A pulse (18) consisting of a number of periods 40 kHz sound waves are emitted from a loud-speaker (15). The sound waves are reflected by the head of the operator and a digital circuit measures the time until the sound pulse has returned to the receiver (16). The distance measured to the head of the operator is then used in order to proportionally control the speed of the motor of the machine. |
