Brian P. Butz

An Intelligent Universal Virtual Laboratory (UVL)

The Universal Virtual Laboratory (UVL) is a realistic, real-time, electrical engineering virtual laboratory. The software developed targets individuals who do not have adequate mobility of their upper bodies to perform laboratory experiments. To provide a more realistic and enhanced learning experience, the users of the virtual laboratory are allowed the freedom to build and test a wide variety of realistic electrical circuits, and be able to perform curriculum-based experiments. Typically, this laboratory would accompany an introductory electrical circuits course sequence. The virtual laboratory also contains an intelligent lab assistant that can guide the student and answer student queries.

An expert system for control system design

The Control Laws Expert Assistant for Rotorcraft (CLEAR) project, which is being performed at Temple University and the Boeing Helicopters Company, is described. CLEAR will assist flight control engineers to design a specific set of flight control systems. The resulting interactive knowledge-based system will analyze mathematical models representing rotorcraft and will design any compensation required to enable the system to meet specifications. There are two major roles that CLEAR plays in the design of a rotorcraft flight control system. First CLEAR determines what kind of compensation, if any, is needed. It then places the compensator at an appropriate location within the system and designs the required compensator. The authors focus on the work being performed at Temple University to give CLEAR its design capability. The rationale for using a knowledge-based system is presented, and the CLEAR architecture is described.<<ETX>>

The Virtual Laboratory for the Disabled

The objective of the Virtual Laboratory for the Disabled is to create a realistic, real-time, electrical engineering virtual laboratory. This project targets individuals who do not have adequate mobility of their upper bodies to perform laboratory experiments. To provide a more realistic and enhanced learning experience, the users of the virtual laboratory are allowed the freedom to build and test a wide variety of realistic electrical circuits, and be able to perform curriculum-based experiments. The main goal is to create an environment similar to a real electrical engineering laboratory, and to offer the user a way to learn the different aspects of instrumentation and circuitry.

Developing an expert system to assist in control system design

This paper addresses the problem of how to develop an expert system that is able to design or to assist in the design of a control system. The discussion includes how to structure the expert system, how to choose the relationship between the symbolic and numerical processor and how to divide the work among the expert system, the computer aided control systems analysis package and the design engineer. A prototype intelligent design associated is presented and an example of a compensator design is given.

An intelligent circuit analysis module to analyze student queries in the universal virtual laboratory

This paper presents an intelligent circuit analysis module that is capable of analyzing electrical circuits and determining equivalence. We discuss the module in context of a National Science Foundation funded project - universal virtual laboratory (UVL). UVL is a virtual electrical engineering laboratory for able and disabled individuals to construct, simulate and understand the characteristics of basic electrical circuits. This paper discusses the development of an intelligent circuit analysis module called the circuit recognizer (CR). The CR is a program that has knowledge of circuit theory concepts, and is capable of using this knowledge to provide assistance to a student while he/she is performing the experiments in UVL. While verifying circuit configuration it identifies errors and provides explanations that guide the student to a better understanding of the experiment. The ultimate objective of the CR is to evaluate the effectiveness of the teaching strategies employed within the UVL as well as to enhance the learning abilities of students

Considerations in the development of a knowledge-based control systems design associate

The authors describe an intelligent design associate (IDA), with emphasis on the techniques used in developing the associate and the mechanics of its operation. The expert-system architecture is described, along with some of the problems encountered when coupling symbolic and numerical systems. Also considered is how to transfer information between the expert system and the analysis package, as well as how the expert system is able to direct the actual sequence of analyses performed by the CACSD (computer-aided control systems design) package. It is demonstrated that not only is such a coupled system feasible, but it is also replicatable in that it can be created with off-the-shelf, commercially available software. An example is included to show that the system is capable of designing simple compensators.<<ETX>>

The learning mechanism of the Interactive Multimedia Intelligent Tutoring System (IMITS)

The Interactive Multimedia Intelligent Tutoring System (IMITS) project is a feasibility study that integrates interactive multimedia with expert system technology. It is a test bed to show that these two complementary technologies may be combined successfully to form a framework useful for any educational material. It combines several commercially available packages and establishes dynamic communications among these packages. This paper describes one aspect of IMITS, the learning mechanism that is controlled by the expert system and that attempts to assist the student learn the material and concepts presented.

Dynamic modeling and feedback control of a side-by-side tandem helicopter

The development of a dynamic model and the design of a feedback controller for reducing torque oscillations of a side-by-side rotor tandem helicopter are described. The tandem helicopter is a multi-input, multi-output system and, for control purposes, can be represented by a linear-time-invariant model. Hamiltons principle is used to develop the dynamic model of the side-by-side rotor tandem helicopter. This method is an excellent tool for analyzing dynamic interaction between various members of an articulated structure. The complete model is given by a set of nonlinear differential equations and can be linearized if necessary. The eigenstructure assignment technique is used for the design of the controller since it allows the designer to place eigenvalues for stability enhancement and desired transient characteristics, and to select eigenvectors for state-variable decoupling. Simulation results show excellent closed-loop performance of the helicopter.<<ETX>>

Considerations in the development of an intelligent design associative

The authors present a simple single-input, single-output, linear, time-invariant, analog control system design example, using an expert system that acts as the design associate. It analyzes the present system, requests the computer-aided control system design (CACSD) package to perform specific computational tasks, looks at the results, decides what type of compensator (in any) need be added to the system, and applies the appropriate compensation heuristic. In addition, the expert system asks for the designers approval of its intended action and allows the designer to modify its suggested design plan.<<ETX>>

Work in Progress: An Intelligent Tutoring System for Forensic Biology

The Interactive Virtual Intelligent System for Scientific Inquiry in a Biology Learning Environment (INVISSIBLE) is software environment being developed as a intelligent tutoring system that provides high school biology students a virtual, hands-on, multimedia learning environment. Using interactive, intelligent software, a student is placed in goal driven scenarios that reflect the authentic experiences of a scientist engaged in using scientific inquiry methods. This paper describes the first of three planned modules, one which involves forensic science and the use of DNA evidence in combination with hairs, fibers, and other evidence in solving a crime scene problem. Core objectives of this module are to increase student learning regarding: (a) knowledge acquisition of content, concepts and principles relevant to genetics, forensic science, and evolutionary biology, (b) relevant scientific process skills and knowledge, and (c) knowledge of nature and methods of science. A demonstration of the software will be given