Robot4 (tm) is a Robotic Arm Movement program where the arm is moved from a given position to a desired position. The program finds the angles necessary for the desired position. Problem came from NASA. Robot4 is an Inverse Problem example. It wants to solve how to move from starting point 'A' to target point 'B'. Solutions to Inverse Problems are easy with Calculus programming language. See file 'Rob4User.fc' for solution code. This is an improved productivity example do to using Calculus-level programming. Industry problems with solutions over the past twenty plus years have been put into a textbook to show the power of Calculus-level Problem-Solving. The textbook as on our website at goal-driven.net/textbooks/. The software architect behind Calculus Compilers was Joe Thames. Help future science & engineers get jobs upon graduation. With usage of the FortranCalculus compiler, one increases their productivity by a factor of twenty! Please visit our textbook at fortranCalculus.info/textbooks/. Thanks!