Sanjeevi Chitikeshi

Intelligent Sensors: Strategies for an Integrated Systems Approach

This paper proposes the development of intelligent sensors as an integrated systems approach, i.e. one treats the sensors as a complete system with its own sensing hardware (the traditional sensor), A/D converters, processing and storage capabilities, software drivers, self-assessment algorithms, communication protocols and evolutionary methodologies that allow them to get better with time. Under a project being undertaken at the Stennis Space Center, an integrated framework is being developed for the intelligent monitoring of smart elements. These smart elements can be sensors, actuators or other devices. The immediate application is the monitoring of the rocket test stands, but the technology should be generally applicable to the Intelligent Systems Health Monitoring (ISHM) vision. This paper outlines progress made in the development of intelligent sensors by describing the work done till date on Physical Intelligent Sensors (PIS) and Virtual Intelligent Sensors (VIS).Copyright

Physical intelligent sensors

This paper proposes the development of intelligent sensors as part of an integrated systems approach, i.e. one treats the sensors as a complete system with its own sensing hardware (the traditional sensor), A/D converters, processing and storage capabilities, software drivers, self-assessment algorithms, communication protocols and evolutionary methodologies that allow them to get better with time. Under a project being undertaken at the NASA s Stennis Space Center, an integrated framework is being developed for the intelligent monitoring of smart elements. These smart elements can be sensors, actuators or other devices. The immediate application is the monitoring of the rocket test stands, but the technology should be generally applicable to the Integrated Systems Health Monitoring (ISHM) vision. This paper outlines progress made in the development of intelligent sensors by describing the work done till date on Physical Intelligent Sensors (PIS). The PIS discussed here consists of a thermocouple used to read temperature in an analog form which is then converted into digital values. A microprocessor collects the sensor readings and runs numerous embedded event detection routines on the collected data and if any event is detected, it is reported, stored and sent to a remote system through an Ethernet connection. Hence the output of the PIS is data coupled with confidence factor in the reliability of the data which leads to information on the health of the sensor at all times. All protocols are consistent with IEEE 1451.X standards. This work lays the foundation for the next generation of smart devices that have embedded intelligence for distributed decision making capabilities.

An Iterative Kalman Filter for a 3D Ultrasonic Position Estimation System

This paper describes an iterative Kalman Filter to increase the accuracy of a dynamic 3D position estimation system. The novelty of the system lies in the fact that a difference in the time of arrivals is used in conjunction with an estimated speed of sound within the system formulation, and the Kalman Filter is used to further increase the accuracy and robustness of the output. The output is a 3D position of the transmitter obtained from the difference in time of arrivals of the wave burst at multiple receivers fixed within an inertial frame. Results are provided to show the increase in accuracy and robustness along with some limitations of the system. The system has many applications the most significant being image guided surgery.Copyright

A Fuzzy Logic Based Decision Making System for Fusing Measurements From an E-Puffer and E-Sniffer Sensing Systems for Detecting Explosives

This is primarily a concept paper and describes a decision making system that fuses the output from cold plasma based E-Puffer and E-Sniffer sensing systems to reliably detect explosive traces. This paper describes research and development of a novel non-contact method to detect explosive bearing personnel, baggage and vehicles that is based on the integration of a multitude of key technologies, primarily cold/atmospheric plasma and pattern recognition/decision making capabilities. This work will ultimately lead to a viable system that can be installed in doorways of buildings, garages, baggage carousals, etc. that will trigger a positive response when detecting explosive traces on personnel, bags or vehicles going thru a doorway. This paper describes the basic product concept and provides preliminary results of the fusion process from a simulated data set of output measurements from the two orthogonal measurement systems.Copyright

Application of intelligent sensors in the integrated systems health monitoring of a rocket test stand

This paper describes the application of intelligent sensors in the Integrated Systems Health Monitoring (ISHM) as applied to a rocket test stand. The development of intelligent sensors is attempted as an integrated system approach, i.e. one treats the sensors as a complete system with its own physical transducer, A/D converters, processing and storage capabilities, software drivers, self-assessment algorithms, communication protocols and evolutionary methodologies that allow them to get better with time. Under a project being undertaken at the NASA Stennis Space Center, an integrated framework is being developed for the intelligent monitoring of smart elements associated with the rocket tests stands. These smart elements can be sensors, actuators or other devices. Though the immediate application is the monitoring of the rocket test stands, the technology should be generally applicable to the ISHM vision. This paper outlines progress made in the development of intelligent sensors by describing the work done till date on Physical Intelligent sensors (PIS) and Virtual Intelligent Sensors (VIS).

Intelligent Sensors for Integrated Health Management Systems

This paper describes work being conducted on the development of intelligent sensors with learning capabilities as part of an integrated systems approach. The integrated systems approach treats the sensor as a complete system with its own sensing hardware (the traditional sensor), A/D converter, processing and storage capabilities, software drivers, self-assessment algorithms, communication protocols and evolutionary methodologies that allow the system to learn its own behavior. The immediate application is the monitoring of rocket test stands, but the technology should be generally applicable to the Integrated Systems Health Monitoring (ISHM) vision. This paper outlines progress made in the development of intelligent sensors by describing the work done till date on Physical Intelligent Sensors (PIS) and Virtual Intelligent Sensors (VIS). The PIS as discussed here consists of a thermocouple used to read temperature in an analog form which is then converted into digital values. A microprocessor collects the sensor readings and runs numerous embedded event detection routines on the digital data. If any event, i.e. spike, drift, noise, is detected, it is reported, stored and sent to a remote system through an Ethernet connection. Hence the output of the PIS is data coupled with a confidence factor in the reliability of the data. The VIS discussed here is a virtual implantation of the PIS in the G2 software environment. The VIS is designed to mirror the operations of the PIS; however, the VIS works on a computer at which digital data is provided as the input. This work lays the foundation for the next generation of smart devices that have embedded intelligence for distributed decision making capabilities.© 2006 ASME

An Intelligent Foot Monitoring System for Diabetic Patients to Prevent Foot Ulcerations

Elevated plantar pressure plays a major role in foot problems in diabetic patients. High pressures interrupt arterial blood flow, which is further compounded by the fact that diabetic patients lose sensory feedback from their feet, hence are not able to change their stance leading to unnatural pressure points. This can lead to dermal ulcerations, necrosis, and ultimately to partial or total amputation of the foot. This paper presents a preliminary design of an intelligent shoe-insert that automatically monitors critical foot parameters in diabetic patients. The objective is to collect information on plantar pressure, temperature and moisture and come up with a system that would help in the prevention of foot ulcerations. This would be accomplished by keeping track of these parameters and sounding alarms when critical thresholds may be reached. This paper describes a comprehensive monitoring system with sensing, A/D, data storage, interpretation, transmission and alarm sounding capabilities in a single unit.Copyright

Improved Accuracy of an Ultrasonic Based Neuro-Navigation System Using Neural Networks

This paper presents the design and development of an ultrasonic based neuronavigation system to be used for real time surgery. The system formulation, hardware and a neural network model is presented that improves the accuracy of the system considerably. 1D, 2D and 3D results from the neural network model are presented along with designs for the physical and electronic hardware. The 3D system presented in this paper eliminates the space intensive camera, has an accuracy better than 1.0 mm in the operating range of about 20–40 cm, makes the system independent of line-of-sight occlusion problems, and is expected to pave the way for accurate fusion models of the future that may account for brain shifts during surgery. The results show that the performance of the proposed system provides many advantages over existing neuro-navigation systems without compromising on the accuracy.Copyright

An Intelligent Systems Approach for an Ultrasonic Based Neuro-Navigation System

This paper shows the feasibility of using an intelligent systems approach to increase the accuracy of a 3D ultrasonic position estimation system for real-time image guided neurosurgery. Current image guided systems use camera based technology that is space-intensive, have an accuracy of about 1.0–2.0 mm, and are prone to occasional failures. The 3D system presented in this paper eliminates the space intensive camera, has an accuracy of around 1.0 mm in the operating range of about 200–400 mm, makes the system independent of line-of-sight occlusion problems, and is expected to pave the way for accurate fusion models of MRI and ultrasonography to account for brain shifts during surgery. Hence, the proposed system provides many more advantages over existing systems without compromising on the accuracy. This paper presents the system formulation, a neural network model that uses the raw signals, the electronic hardware for data acquisition and processing as well as simulation and actual results.Copyright