Asad M. Madni

Common design techniques for BEI GyroChip quartz rate sensors for both automotive and aerospace/defense markets

In the early 1990s, Systron Donner Inertial Division (SDID), a subsidiary of BEI Technologies, Inc., possessed a new solid-state rate gyroscope technology that had not yet matured or captured a significant market share. Even though some success had been achieved in defense missile applications, a strategy was clearly needed to further develop the technology and lay the foundation for future growth. The strategy search led to discovery of a leading edge automotive brake system application, which, in turn, led to a radical change in design and manufacturing approaches, as well as a dramatic increase in revenues. The resultant radical cost-reduction of quartz rate sensor (QRS) components has benefit for both the automotive and the aerospace and defense (A&D) applications. Commonality of design and design techniques is leveraging high-volume, low-cost automotive components into low-volume A&D products.

Towards optimization of a real-world Robotic-Sensor System of Systems

The problem of threat detection in an unstructured environment is considered. Three systems, comprising of robots and sensors, are proposed to form a system of systems (SoS) to find a solution to the problem. System interactions are defined to provide a framework for formulation as an SoS optimization problem. Different cost and objective functions are introduced for optimization of local criteria. Using different weights, a linear combination of the local cost and objective functions is obtained to propose a global objective function. An algorithm is suggested to find an optimum value for the global objective function leading towards optimization of the SoS.

VHDL Implementation For a Fuzzy Logic Controller

This paper describes the implementation for a basic fuzzy logic controller in Very High speed integrated-circuit Hardware-Description Language (VHDL). It is not intended as an introduction to fuzzy logic control methodology; instead, we try to demonstrate the implementation of a fuzzy logic controller through the use of the VHDL code. Use of the hardware description language (HDL) in the application is suitable for being implemented into an Application Specific Integrated Circuit (ASIC) and Field Programmable Gate Array (FPGA). The main advantages of using the HDL approach are rapid prototyping, and allowing usage of powerful synthesis tools such as Xilinx ISE, Synosys, Mentor Graphic, or Cadence to be targeted easily and efficiently.

Hierarchical Aggregation and Intelligent Monitoring and Control in Fault-Tolerant Wireless Sensor Networks

The primary idea behind deploying sensor networks is to utilize the distributed sensing capability provided by tiny, low powered, and low cost devices. Multiple sensing devices can be used cooperatively and collaboratively to capture events or monitor space more effectively than a single sensing device. The realm of applications envisioned for sensor networks is diverse including military, aerospace, industrial, commercial, environmental, and health monitoring. Typical examples include: traffic monitoring of vehicles, cross-border infiltration detection and assessment, military reconnaissance and surveillance, target tracking, habitat monitoring, and structure monitoring, to name a few. Most of the applications envisioned with sensor networks demand highly reliable, accurate, and fault-tolerant data acquisition process. In this paper, we focus on innovative approaches to deal with multivariable, multispace problem domains (data integrity, energy-efficiency, and fault-tolerant framework) in wireless sensor networks and present novel ideas that have practical implementation in developing power-aware software components for designing robust networks of sensing devices.

Multi-Criteria Decision Making in Sensor Networks

This decision making process for a mobile robot can be adapted to clusters of sensor nodes rather than an individual sensor node. Preference can be given to a particular cluster for management (power management, node density management, etc.) based on activity level, the number of sensor nodes, and the importance of the activity. If the number of nodes is critical for the given application, then it gets a high weighting factor and would require some nodes to be put to sleep. We change the behavior of the network by tuning one of the parameters (increasing sleep time) based on the needs of the application. We intelligently analyzed the characteristic of a deployed sensor network for a given application and adaptively changed its operational behavior to suit the changing demands. We showed that appropriate sensor action needs to be scheduled in order to achieve maximum utility.

A smart linear actuator for fuel management system

The design of a novel smart linear actuator for fuel management systems is presented. The actuator integrates linear voice coil motor technology with linear position sensing feedback technology to actuate a load across a linear trajectory, in a controlled fashion. Three types of sensor technologies have been developed for this actuator: potentiometric, piezoresistive, and a linear non-contacting technique. Each of these techniques measure the position of the actuators shaft, along a straight line of actuation. Although developed primarily for automotive fuel efficiency enhancement and emission control, the smart actuator is ideally suited for numerous applications in the commercial, industrial, medical, transportation, and aerospace and defense industries.

Intelligent sensing in dynamic environments using markov decision process.

In a network of low-powered wireless sensors, it is essential to capture as many environmental events as possible while still preserving the battery life of the sensor node. This paper focuses on a real-time learning algorithm to extend the lifetime of a sensor node to sense and transmit environmental events. A common method that is generally adopted in ad-hoc sensor networks is to periodically put the sensor nodes to sleep. The purpose of the learning algorithm is to couple the sensor’s sleeping behavior to the natural statistics of the environment hence that it can be in optimal harmony with changes in the environment, the sensors can sleep when steady environment and stay awake when turbulent environment. This paper presents theoretical and experimental validation of a reward based learning algorithm that can be implemented on an embedded sensor. The key contribution of the proposed approach is the design and implementation of a reward function that satisfies a trade-off between the above two mutually contradicting objectives, and a linear critic function to approximate the discounted sum of future rewards in order to perform policy learning.

A Differential Capacitive Torque Sensor With Optimal Kinematic Linearity

This paper presents a new design for a torque sensor based on a differential capacitive technology. An arc-radial mechanism is adopted to achieve high rotary/radial motion linearity. Kinematic model of this assembly is derived via vector loop equations. A nonlinearity index is formulated and practical kinematic constraints are imposed. Results show that very high kinematic linearity could be achieved by this new device

Full circle commercialization of a dual-use micromachined quartz rate sensor technology

Commercialization of MEMS gyroscopes for high volume, low-cost applications has posed significant challenges for many companies. This paper describes the strategic vision, commercialization efforts and key technology roadmap milestones which were defined and implemented by BEI Technologies, Inc. at its subsidiary, Systron Donner Inertial Division (SDID) in order to commercialize its quartz rate sensor (QRS) technology (referred to as the GyroChipreg) to satisfy the needs of Aerospace and Defense (A&D), and automotive markets. Portions of this paper are adapted from earlier papers by Madni and Costlow

Fault-Tolerant Data Acquisition in Sensor Networks

The integrity of data has tremendous effects on the performance of any data acquisition system. Noise and other disturbances can often degrade the information or data acquired from these systems. Devising a fault-tolerant mechanism in wireless sensor networks is very important due to the construction and deployment characteristics of these low powered sensing devices. More over, due to the low computation and communication capabilities of the sensor nodes, the fault-tolerant mechanism should have a very low computation overhead. In this paper, we present a novel methodology to hierarchically design and implement a protocol for checking the integrity of data from a sensor-node.