Dental robot and oral navigation method

A dental robot for oral and maxillofacial surgical operations, comprising:

• a dental treatment chair;
• a tandem positioning arm comprising a pedestal, several positioning arms and a jacket, wherein the tandem positioning arm is fixedly mounted on an equipment base of the dental treatment chair by the pedestal, the jacket is configured to clamp surgical instruments,;
• and the pedestal, the several positioning arms and the jacket are connected in series in sequence by rotary joints;
• a joint angle measuring device is-mounted at each of the rotary joints;
• a servo torque motor is-mounted at each of the rotary joints in the tandem positioning arm;
• a visual navigator fixedly mounted on the equipment base of the dental treatment chair through a support arm, wherein the visual navigator is configured to track visual markers on an area to be operated in real time to detect their spatial positions in real time;
• and
• wherein a contact stiffness of the tandem positioning arm is determined based on a preset working area of the surgical instruments in a three-dimensional image of a patient's oral cavity and the coordinate position of the surgical instruments in a coordinate system of three-dimensional image, and the contact stiffness is the sensitivity of the tandem positioning arm when the tandem positioning arm is dragged by dentists;
• wherein an output torque of the servo torque motor at each of the rotary joints is adjusted based on the contact stiffness of the tandem positioning arm to give the dentists force-sensitive feedback;
• and
• wherein, when the surgical instruments are located in the preset working area, the contact stiffness is zero to enable the tandem positioning arm to be dragged freely, and when the surgical instruments are close to a non-preset working area, the contact stiffness is not zero and increases as the distance to the non-preset working area decreases.