Surgical system with user adaptable techniques based on tissue type

A generator for delivering energy to a surgical instrument for coagulating and dissecting tissue, the surgical instrument comprising an end effector at a distal end thereof, the end effector configured to interact with tissue, the end effector comprising a clamp arm, an ultrasonic blade, a force sensor in communication with the processor and configured to measure a force applied to tissue located between the clamp arm and the ultrasonic blade, and a temperature sensor in communication with a processor, an ultrasonic transducer acoustically coupled to the ultrasonic blade and configured to receive a drive signal from the generator to cause ultrasonic motion of the ultrasonic blade and deliver energy to the ultrasonic blade, the generator comprising:

• a drive circuit configured to deliver a drive signal to an ultrasonic transducer;
• and
• a processor configured to control energy delivered by the drive circuit to the ultrasonic transducer based on a type of tissue interacting with the end effector;
• wherein the processor is configured to:
• receive a measurement of force applied to tissue by the end effector, ultrasonic motion of the ultrasonic blade, and a rate of heat generated by the end effector;
• determine the type of tissue interacting with the end effector based on a tissue coefficient of friction, wherein the tissue coefficient of friction is determined based on the force applied to the tissue by the end effector, the ultrasonic motion of the ultrasonic blade, and a rate of heat generated by the end effector;
• and
• dynamically control the drive signal delivered to the ultrasonic transducer based on the type of tissue interacting with the end effector.

A method of coagulating and dissecting tissue, the method comprising:

• measuring, by a force sensor, a force being applied to a tissue by an end effector disposed on a distal end of a surgical instrument configured to interact with the tissue, the end effector comprising a clamp arm, an ultrasonic blade acoustically coupled to an ultrasonic transducer, a force sensor in communication with a processor and configured to measure a force applied to tissue located between the clamp arm and the ultrasonic blade, and a temperature sensor;
• determining, by the processor, a tissue coefficient of friction based on the measured force applied to the tissue by the end effector, ultrasonic motion of the end effector caused by energy delivered thereto from a generator, and a rate of heat generated by the end effector;
• determining, by the processor, a type of tissue interacting with the end effector based on the tissue coefficient of friction;
• and
• delivering, by a drive circuit, a drive signal to the ultrasonic transducer to interact the ultrasonic blade with the tissue based on the determined type of tissue.