Generalized Inverses for Finite-Horizon Tracking
Abstract
Control and communication issues are traditionally "decoupled" in discussions of decision and control problems, as this simplifies the analysis and generally works well for classical models. This fundamental assumption deserves re-examination as control applications spread into new areas where system complexity is significant. Such areas include the coordinated control of aerial vehicles (UAVs), MEMS devices, multi-joint manipulators, and other settings in which many systems must share the attention of a decision maker. The author considers a new class of sampled-data systems (termed "computer-controlled systems") that offer the possibility of jointly optimizing between control and communication goals. Computer-controlled linear, time-invariant (LTI) systems can be viewed as linear operators between appropriate inner-product spaces. The generalized inverses of these operators are used to solve a class of finite-horizon tracking problems. This paper presents a prototype computer-controlled LTI system, an N-step look-ahead tracking problem, and a motion control system with limited communication. The latter discusses the Harvard Robotics Lab planar manipulator. The manipulator consists of two robotic fingers, each having two joints. The joints are driven by motors that contain integrated PID controllers, operating at 4KHz. A computer communicates with the motors through an RS-232 serial port. All four motors are connected to the same serial port so that the computer can address one motor at a time, at a rate of 20Hz. The manipulator uses joint, visual, and tactile feedback to locate, grasp, and move objects along user-specified trajectories. The author discusses the manipulator in terms of dynamic performance, uniform attention, and nonuniform attention.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2000
- Accession Number
- ADA438590
Entities
People
- Dimitris Hristu
Organizations
- Harvard University