The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 04, 2024
Filed:
Oct. 09, 2020
Cmr Surgical Limited, Cambridge, GB;
Ivan Cronin, Cambridge, GB;
Hamish Henderson, Cambridge, GB;
CMR SURGICAL LIMITED, Cambridge, GB;
Abstract
A method of testing a motor of a robot arm for a fault during a start-up procedure of the robot arm. The robot arm comprises a first link connected to a second link by a joint, the joint permitting the second link to move relative to the first link. The motor is for driving the joint and is a multiple-phase motor, each phase of the motor comprising a motor winding and a motor drive circuit for applying power to the motor winding from a power supply rail and for applying drive signals to the motor winding. The method comprises, in the following order: (i) driving the motor to a known state; (ii) connecting a first phase only of the motor to the power supply rail; (iii) driving a Pulse Width Modulation (PWM) signal through the motor drive circuit of the first phase of the motor; (iv) driving the motor to a known state; (v) with the first phase of the motor disconnected from the power supply rail, driving the PWM signal through the motor drive circuit of the first phase of the motor; and (vi) repeating steps (ii) to (v) for each of the other phases of the motor; the method further comprising, during each of steps (i) to (vi), testing whether the current from the power supply rail to the motor drive circuit exceeds a current limit.