Mohamed Dekhil

Instrumented Sensor System Architecture

Sensor systems are becoming ubiquitous throughout society, yet their design, construction, and operation are still more of an art than a science. In this paper, we define, develop, and apply a formal se mantics for sensor systems that provides a theoretical framework for an integrated software architecture for modeling sensor-based con trol systems. Our goal is to develop a design framework that allows the user to model, analyze, and experiment with different versions of a sensor system. This includes the ability to build and modify multisensor systems and to monitor and debug both the output of the system and the effect of any modification in terms of robustness, efficiency, and error measures. The notion of Instrumented Logi cal Sensor Systems (ILSS) that are derived from this modeling and design methodology is introduced. The instrumented sensor ap proach is based on a sensori-computational model that defines the components of the sensor system in terms of theirfunctionality, accu racy, robustness, and efficiency. This approach provides a uniform specification language to define sensor systems as a composition of smaller, predefined components. From a software-engineering standpoint, this addresses the issues of modularity, reusability, and reliability for building complex systems. An example is given that compares vision and sonar techniques for the recovery of wall pose.

Smart sensor snow

We propose to deploy and exploit a large number of inexpensive sensors to obtain information or trigger actions over a wide geographic area. Sensors may be of diverse physical natures: acoustic, IR, seismic, chemical, magnetic, thermal, etc. We describe three major issues: (1) sensor distribution patterns, (2) local sensor frames, and (3) autonomous robot sensor snow exploitation techniques.

URK: Utah Robot Kit-a 3-link robot manipulator prototype

In designing robot manipulators, the interaction between several modules (S/W, VLSI, CAD, CAM, robotics, and control) illustrates an interdisciplinary prototyping environment that includes different types of information that are radically different but combined in a coordinated way. This paper describes the analysis and design of a 3-link robot manipulator prototype as part of a research project for building a prototyping environment for electromechanical systems. This prototype robot can be used as an educational tool in robotics and control classes.<<ETX>>

Industrial inspection and reverse engineering

Proposes a new design for inspection and reverse engineering environments. The authors have designed and experimented with such an environment for capturing sense data of mechanical parts in an intelligent way. They construct a sensing /spl rarr/ CAD interface for the automatic reconstruction of parts from visual data. They briefly discuss the use of the dynamic recursive finite state machine (DRFSM) as a new discrete event dynamic system (DEDS) tool for controlling inspection and exploration. They also implement a graphical interface for designing DRFSM DEDS controllers.<<ETX>>

Instrumented logical sensor systems-practice

In previous work (1993,1996), we introduced the notion of instrumented logical sensor systems (ILSS) that are derived from a modeling and design methodology. The instrumented sensor approach is based on a sensori-computational model which defines the components of the sensor system in terms of their functionality, accuracy, robustness and efficiency. This approach provides a uniform specification language to define sensor systems as a composition of smaller, predefined components. From a software engineering standpoint, this addresses the issues of modularity, reusability, and reliability for building complex multisensor systems. In this paper, we demonstrate the practicality of this approach and discuss several design and implementation aspects in the context of mobile robot applications.

Sonar sensing strategies

Develops theoretical and practical techniques to recover the pose of planar surfaces with minimal sensor readings and motion. A proof is given that two sonar readings suffice to precisely locate a single planar surface that returns the sonars signal. An implementation is described that takes into account the physical restrictions on actual Polaroid sensors and experiments are described based on actual Polaroid sensor data.

Sensor-based distributed control scheme for mobile robots

We present a sensor-based distributed control scheme for mobile robots. This scheme combines centralized and decentralized control strategies. A server-client model is used to implement this scheme where the server is a process that caries out the commands to be executed, and each client is a process with a certain task. The clients are running in parallel issuing commands to the server which selects the command to be executed based on a predefined priority scheme. In this scheme, a collision avoidance client is running all the time with the highest priority. This improves the performance of the other clients since it removes the burden of avoiding obstacles and allows each client to concentrate on performing its task. The logical sensor approach is used to model the sensory system which provides different levels of data representation with tolerance measures and analysis. The simulation results of this model are presented with a brief discussion and conclusion on these results.

A perception framework for inspection and reverse engineering

A perception framework for intelligent inspection and reverse engineering is addressed. The use of discrete event dynamic systems (DEDS) to guide the sensing of mechanical parts is investigated. Dynamic recursive finite state machines (DRFSMs) are introduced as a new DEDS tool for utilizing the recursive nature of the mechanical parts under consideration. The proposed framework uses DRFSM DEDS for constructing an observer for exploration and inspection purposes. A sensing /spl rarr/ CAD interface is constructed for the automatic reconstruction of parts from visual data. A graphical interface for designing DRFSM DEDS controllers is implemented.<<ETX>>

Discrete event control for inspection and reverse engineering

We address the problem of intelligent sensing in this work. In particular, we use discrete event dynamic systems (DEDS) to guide the sensing of mechanical parts for industrial inspection and reverse engineering.<<ETX>>

Concurrent design of a three-link manipulator prototype

Abstract This paper presents an affordable and comprehensive robotic model of critical aid to any engineering school involved in teaching robotics. We present the stages of designing a three-link robot manipulator prototype that was built as part of a research project for establishing a prototyping environment for robot manipulators. Building this robot helped to determine the required subsystems and interfaces for building the prototyping environment, and provided hands-on experience for real problems and difficulties that are addressed and solved using this environment. The robot is now successfully used as an educational tool in robotics and control classes.