Tracking system, tracking device and tracking method

A tracking device, comprising:

• an optical module, configured to capture image data in a first detection field;
• an ultrasonic module, configured to collect ultrasonic data in a second detection field different from the first detection field;
• and
• a processor, configured to determine a relative position of a target device relative to the tracking device in a third detection field according to at least one of the image data and the ultrasonic data,
• wherein the third detection field is larger than the first detection field and larger than the second detection field,
• wherein the processor is configured to calculate a first weighted position according to the image data and a second weighted position according to the ultrasonic data, the processor is configured to calculate the relative position of the target device according to the first weighted position and the second weighted position when the target device is simultaneously detected in the first detection field and the second detection field,
• wherein the ultrasonic module comprises at least three ultrasound transceivers, the processor calculates at least three distances from each of the at least three ultrasonic transceivers to the target device according to the ultrasonic data, the processor comprises an acoustic position solver, the acoustic position solver is configured to generate an acoustic-solved position of the target device according to the at least three distances, the processor calculates the acoustic-solved position with a second weight to generate the second weighted position,
• wherein the second weight is negative correlated to an average distance of the at least three distances.

A tracking method for tracking a first device by a second device, comprising:

• capturing, by an optical module of the second device, image data in a first detection field;
• collecting, by an ultrasonic module of the second device, ultrasonic data in a second detection field different from the first detection field;
• determining, by a processor of the second device, a relative position of the first device relative to the second device in a third detection field according to at least one of the image data and the ultrasonic data, wherein the third detection field is larger than the first detection field and larger than the second detection field;
• calculating, by the processor, a first weighted position by a first weight according to the image data and a second weighted position according to the ultrasonic data;
• calculating, by the processor, the relative position of the first device according to the first weighted position and the second weighted position when the first device is simultaneously detected in the first detection field and the second detection field;
• calculating, by the processor, at least three distances from at least three ultrasonic transceivers of the ultrasonic module to the first device according to the ultrasonic data;
• generating, by an acoustic position solver of the processor, an acoustic-solved position of the first device according to the at least three distances;
• and
• calculating, by the processor, the acoustic-solved position with a second weight to generate the second weighted position, wherein the second weight is negative correlated to an average distance of the at least three distances.