Method for controlling zero-return of servo of robot, and servo and robot with enhanced zero-return

A servo with enhanced zero-return, comprising:

• a motor;
• a speed reducer electrically connected to an output shaft of the motor;
• a first encoder electrically connected to the output shaft of the motor;
• a second encoder electrically connected to the output shaft of the speed reducer;
• a motor controller electrically connected to the motor, the first encoder, and the second encoder, the motor controller comprising one or more processor and a storage;
• and
• one or more computerized instructions stored in the storage and configured to executed to execute a method, the method comprising:
• outputting an activation command to the motor, wherein the activation command comprises a zero-return command;
• reading a default zero-point of the output shaft of the motor (w1) and a default zero-point of the output shaft of the speed reducer (w2);
• a first detecting step comprising detecting a current position of the output shaft of the speed reducer (w4) by the second encoder;
• a first comparing step comprising comparing the default zero-point of the output shaft of the speed reducer (w2) with the current position of the output shaft of the speed reducer (w4);
• a first driving step comprising driving the output shaft of the motor (w1) to return until the default zero-point of the output shaft of the speed reducer (w2) is the same with the current position of the output shaft of the speed reducer (w4) in response to the default zero-point of the output shaft of the speed reducer (w2) being not the same with the current position of the output shaft of the speed reducer (w4);
• a second detecting step comprising detecting a current position of the output shaft of the motor (w3) by the first encoder;
• a second comparing step comprising comparing the default zero-point of the output shaft of the motor (w1) with the current position of the output shaft of the motor (w3);
• and
• a second driving step comprising driving the output shaft of the motor to return until the default zero-point of the output shaft of the motor (w1) is the same with the current position of the output shaft of the motor (w3) in response to the default zero-point of the output shaft of the motor (w1) being not the same with the current position of the output shaft of the motor (w3).

A robot with enhanced zero-return, comprising a servo, wherein the servo comprises:

• a motor;
• a speed reducer electrically connected to an output shaft of the motor;
• a first encoder electrically connected to the output shaft of the motor;
• a second encoder electrically connected to the output shaft of the speed reducer;
• a motor controller electrically connected to the motor, the first encoder, and the second encoder, the motor controller comprising one or more processors and a storage;
• and
• one or more computer programs stored in the storage and configured to executed by the one or more processors, the one or more computer programs controlling the servo to:
• output an activation command to the motor, wherein the activation command comprises a zero-return command;
• read a default zero-point of the output shaft of the motor (w1) and a default zero-point of the output shaft of the speed reducer (w2);
• detect a current position of the output shaft of the speed reducer (w4) by the second encoder;
• compare the default zero-point of the output shaft of the speed reducer (w2) with the current position of the output shaft of the speed reducer (w4);
• drive the output shaft of the motor (w1) to return until the default zero-point of the output shaft of the speed reducer (w2) is the same with the current position of the output shaft of the speed reducer (w4) in response to the default zero-point of the output shaft of the speed reducer (w2) being not the same with the current position of the output shaft of the speed reducer (w4);
• detect a current position of the output shaft of the motor (w3) by the first encoder;
• compare the default zero-point of the output shaft of the motor (w1) with the current position of the output shaft of the motor (w3);
• and
• drive the output shaft of the motor to return until the default zero-point of the output shaft of the motor (w1) is the same with the current position of the output shaft of the motor (w3) in response to the default zero-point of the output shaft of the motor (w1) being not the same with the current position of the output shaft of the motor (w3).