Robotic Sensing. Guiding Undergraduate Research Projects. Arye Nehorai

Transcription

1 Department of Electrical & Systems Engineering Robotic Sensing Guiding Undergraduate Research Projects Arye Nehorai Center for Sensor Signal and Information Processing (CSSIP Signal Processing Innovations in Research and Information Technologies (SPIRIT Lab January 00

2 Department of Electrical & Systems Engineering ESE Launching Multi-team Robotic Sensing Project We created a new multi-team undergraduate project entitled Robotic Sensing Students will take leadership roles in multi-semester projects Students will implement sensor systems for mobile robots that make autonomous decisions based on the sensed environment These systems include acoustic, chemical, RF electromagnetic, infra-red, and visual sensors The project is multidisciplinary, involving hardware, signal processing, imaging, control, communications, and computer interfaces It is led by the department chair, Dr. Arye Nehorai

3 Robotic Sensing Multi-Team Project Hardware Design Software/Interface Design Algorithm Design Physical/Chemical/Biological Background Graphical display of variables of interest Preprocessing Algorithms (Digital filters: FIR, IIR Transducer/Sensor Selection Signal Conditioning (analog filter, signal amplifier Graphical User Interface (GUI Design Statistical Signal Processing Algorithms Data Acquisition System (sampling rate and resolution Microcontroller Actuators (motors Robotic Platform Communication User-defined System and Algorithms parameters Real-time Data Processing Arquitectures Central Processing

4 Robotic Sensing Multi-Team Project Microphones Microcontroller Chemical Sensors Ultrasound Sensors Servo Motor Data Acquisition Infrared Sensors Acoustic Vector Sensors Camera Sensors

5 Robotic Sensing: Current Projects Advisor: Dr. Arye Nehorai Microphones Microcontroller Chemical Sensors Adaptive source position estimation (Raphael Schwartz and Zachary Knudsen Ultrasound Sensors Servo Motor Data Acquisition Chemical source position estimation (Joy Chiang Acoustic Vector Sensors Real-time tracking (Andrew Weins Acoustic vector sensors for source location (Evan Nixon

6 Robotic Sensing: Adaptive Microphone Arrays Goal: To modify microphone array configuration adaptively for improving the performance in estimating acoustic source position using generalized crosscorrelation algorithms. NTX Pair of Motors Robotic Platform Sensing Acoustic Field Pair of Microphones + DAQ Computer for Central Processing Source Position Estimation Microcontroller Microphones Feedback Sensing parameter adaptation NTX Sensing Acoustic Field Pair of Motors Pair of Microphones + DAQ Robotic Platform Servo Motor Current projects supervised by Professor Arye Nehorai Chase LaFont, Algorithms for sensing parameter adaptation, since summer 009 Raphael Schwartz and Zachary Knudsen, Data architectures for real-time acoustic source position estimation, since summer 009

7 Hardware Design Physical/Chemical/Biological Background = cos v s ( TimeDelay d y y* Source P [ + ] * x = y * = P R?? x * d P d L x Sensor

8 Algorithm Design Physical/Chemical/Biological Background Statistical Signal Processing Algorithms v s ( TimeDelay = cos d y y* Source R P [ + ] * x = * y = P x ( t x ( t Measurement Model = = s ( t + n ( t α s ( t + D + n ( t?? x * d P d L x Sensor x x Time-delay estimation y H ( f Cross Correlation H ( f y Peak Detection Dˆ Preprocessing Algorithms FIR filters IIR filters DOA estimation at each microphone i = cos v Dˆ s d i

9 Algorithm Design (Cont. Statistical Signal Processing Algorithms Region of Ambiguity Higher Resolution Microphones pairs Xs =.33 Ys =.405 Error = Xs =.949 Ys =.944 Error = Xs =.949 Ys =.045 Error =

10 Hardware Design Transducer/Sensor Selection Signal Conditioning Data Acquisition System Koss M-8 electret microphones DC Blocking Filter Diagram DAQ Microcontroller Actuators Robotic Microphone array NXT ARM7 Servomotor

11 Software/Interface Design Graphical User Interface (GUI Design GUI using Matlab User-defined System and Algorithms parameters Real-time Data Processing Arquitectures Graphical display of variables of interest Sensor array configuration Data acquisition system Preprocessing filters Cross-correlation algorithm Spectrogram Estimated location Real time source location

12 Robotic Microphone Array Measurements Statistical Signal Processing & Position Control Algorithms New array Configuration y PC y x x Resolution Error

13 Robotic Microphone Array Robotic Platform Computer for Central Processing NTX Pair of Motors Sensing Acoustic Field Pair of Microphones + DAQ Source Position Estimation Feedback Sensing parameter adaptation NTX Pair of Motors Sensing Acoustic Field Pair of Microphones + DAQ Robotic Platform

14 Microphone Array Demonstration Demonstration at the WUSTL Undergraduate Research Symposium, October 4 th, 009

15 Microphone Array Demonstration (Cont. Demonstration at the WUSTL Undergraduate Research Symposium, October 4 th, 009

16 Robotic Sensing: Acoustic Vector Sensors Goal: Estimate the position of an acoustic source using spatial and temporal measurements of pressure and particle acoustic field Acoustic vector sensor (AVS Measurement model Acoustic source Microphones Pressure sensor AVS Far acoustic field Particle velocity sensor Euler equation pressure at position r and time t particle velocity at position r and time t speed of sound, direction of particle velocity Ambient pressure Current projects supervised by Professor Arye Nehorai Ian Beil and Evan Nixon, Acoustic vector sensors for source location, since Fall 009

17 Robotic Sensing: Acoustic Vector Sensors (Cont. Array of AVS Capon Spectra Signal conditioner DAQ Above: Diagram of experimental setup; Power distribution as a function of azimuth and elevation. The red arrow indicates the maximum spectral value. Right: Experimental setup at SPIRIT LAB

18 Robotic Sensing: Current Projects Advisor: Dr. Arye Nehorai Microphones Microcontroller Chemical Sensors Ultrasound Sensors Servo Motor Infrared Sensors Data Acquisition Acoustic Vector Sensors Camera Sensors