Apparatus and method for an autonomous robotic system for performing activities in a well

A robot for repairing and maintaining oil and gas wells, comprising:

• a. a control system which uses sensor data:
• i. to maintain force against an inside wall of a tubing to prevent slippage;
• ii. to control advancing of the robot against obstacles in its path;
• iii. to detect leaks in the robot's hydraulics;
• and
• iv. to allow the robot to perform tasks,
• b. a motion sensor connected to the control system;
• c. means for using well liquids for self-propulsion, and
• d. an inch-worm drive for self propulsion, wherein:
• i. the inch-worm drive has a first arm having a first clamp, and a second arm having a second clamp, and the inch-worm drive moves by extending the first arm and clamping the first clamp against the inside wall of the tubing, then extending the second arm forward from the first arm, and clamping the second clamp against the wall, then releasing the first clamp, and moving the first arm to clamp the wall with the first clamp, close to the second clamp;
• ii. the clamps are hydraulically actuated to allow a control arm force, control slippage, and dithering the force element on the wall to control free fall of the tool into the well to save battery power;
• iii. the clamps also serve as centralizing mechanisms to permit better control of the robot's direction, and
• iv. the means for using well liquids comprises an iris having a controllable circumference.