Intuitive Physics

Part 1: Multibody Parameter Estimation

MIT 6.4210/2:

Robotic Manipulation

Fall 2022, Lecture 19

Follow live at https://slides.com/d/9swJBqk/live

(or later at https://slides.com/russtedrake/fall22-lec19)

American Controls Conference (ACC), 1991

"This controller assumes that the object is a point particle and that the aerial trajectory of the projectile moves along a ballistic path affected only by gravity, which imparts a downward acceleration of ... \(-9.8 m/s^2\)."

"Second, it assumes that the gripper release velocity \(v\) directly determines the velocity of the projectile. This is not true since the object is often not grasped at the center of mass, nor is the object completely immobilized by the grasp prior to release."

"Many dynamic systems to be controlled have constant or slowly-varying uncertain parameters... The basic idea in adaptive control is to estimate the uncertain plant parameters (or, equivalently, the corresponding controller parameters) on-line based on the measured system signals, and use the estimated parameters in the control input computation. An adaptive control system can thus be regarded as a control system with on-line parameter estimation."

"Research in adaptive control started in the early 1950's in connection with the

design of autopilots for high-performance aircraft, which operate at a wide range of speeds and altitudes and thus experience large parameter variations. Adaptive control was proposed as a way of automatically adjusting the controller parameters in the face of changing aircraft dynamics. But interest in the subject soon diminished due to the lack of insights and the crash of a test flight [emphasis added]. It is only in the last decade..."