•Decision and Control in Distributed Cooperative Systems: This research uses novel matrix-based approaches for decision and control in distributed cooperative systems such as wireless sensor networks. A novel matrix-based Discrete Event Controller has been implemented for task planning and resource dispatching in a network consisting of stationary ground sensors and mobile agents also known in the literature as mobile wireless sensor networks. The use of shared resources in such systems can sometimes cause a phenomenon called system deadlock, where all the processes in the system come to a standstill. This work presents a new matrix-based algorithm that has been implemented for deadlock avoidance in a system with shared resources and dynamic resource assignment. The analysis of deadlock is based on certain Petri Net objects in such systems called critical siphons and critical subsystems.

•Deadlock Avoidance for Free-Choice Systems: The analysis of deadlock avoidance becomes even more difficult when routing of tasks and resources are involved. The critical siphons and critical subsystems have to be redefined. This research presents a new matrix-based approach for deadlock avoidance in such systems. This is a generalized approach that can be used for systems with or without routing. The work also presents a method for tackling a certain pathological case called second order deadlocks.

•Dynamic Decisions using Matrix-based Dempster Shafer Theory: In routing systems, dynamic decisions have to be made. In the presence of numerous agents which act as resources, a collective decision can be made based on the individual decisions of agents. This method is called data fusion. Dempster Shafer (DS) theory has been extensively used in the past for data fusion since it provides an excellent framework for conditions involving uncertainty. But the mathematics of computation involving DS belief functions is difficult to fathom because of the many summations over set inclusions and intersections. The equations are often difficult to comprehend and discourage readers due to their complexity, and are often difficult to implement using software. This research provides a new matrix formulation for updating evidence and computing beliefs and plausibilities in DS theory. The work also shows how evidence theory can be used in routing systems for Condition Based Maintenance.

•Trust-based Collaborative Control for Teams in Communication Networks: This research presents a framework for trust propagation and maintenance in a network of nodes or mobile agents that yields global consensus of trust under rich enough communication structure graphs. This work considers the case where the graph structure is a time-varying function of the trusts based on the graph connectivity. This makes the trust consensus scheme bilinear. This trust consensus is incorporated into cooperative control laws that depend on local information from neighboring nodes, yet yield team-wide desired behavior such as flocking and formations.
 

•LabVIEW toolkit for TinyOS: LabVIEW toolkit developed for TinyOS offers ease of programming wireless sensor such as mica2. The GUI is user-friendly and intuitive. For more details click here.

• BE in Electronics & Telecommunication, University of Mumbai, India, 2002.
• MS in Electrical Engineering,  University of Texas at Arlington, USA, Aug 2005.

• Ph.D in Electrical Engineering,  University of Texas at Arlington, USA, 2005-2008.

•Automation and Robotics Research Institute, Fort Worth, USA

Research Assistant for design and development of Wireless Sensor Network for Mobile Robot Test bench using Crossbow Sensors.

•UTA Department of Electrical Engineering, Arlington, USA

Teaching Associate for Control System Design Capstone course.

•UTA Housing and Management, Arlington, USA

Student Assistant.

•IndiaGames Ltd, Mumbai, India

Software Programmer to design and develop PC (Flash Based) & Console and Wireless Games.

•Retort Software Pvt Ltd, Mumbai, India

Project Intern for designing and implementing Radio Locators (Land Based Radio Tracking Systems). Software simulation of the Project designed and developed in C++.

P. Ballal, F. Lewis, "Condition-Based Maintenance using Dynamic Decisions by Petri Nets and Dempster Shafer Theory: A Matrix-Based Approach", Transactions on Institute of Measurement and Control, to appear.

P. Ballal, A. Trivedi, F. Lewis, "Deadlock avoidance policy in Mobile Wireless Sensor Networks with Free Choice Resource Routing", International Journal of Advanced Robotic Systems, September 2008, to appear.

P. Ballal, F. Lewis, J. Mireles Jr., K. Sreenath, "Deadlock avoidance for free choice multi-reentrant flow lines: Critical siphons and critical subsystems", submitted to IEEE Transactions on Automation Science and Engineering, 2007.

A. Tiwari., P. Ballal., P., F.L. Lewis., 2007. Energy-efficient wireless sensor network design and implementation for condition-based maintenance, ACM Trans. Sens. Netw. 3, 1, Article 1 (March 2007), 23 pages. DOI = 10.1145/1210669.1210670

P. Dang., P. Ballal., F. Lewis., D. Popa., "Real Time Relative and Absolute Dynamic Localization of Air-Ground Wireless Sensor Networks.," Journal of Intelligent and Robotic Systems, 2007, to appear.

A. Das., D. Popa., P. Ballal., F.L. Lewis., “Data-logging and Supervisory Control in Wireless Sensor Networks”, in ACIS Int’l Journal of Wireless and Mobile Computing,  2007, to appear.

V. Giordano, P. Ballal, F.L. Lewis, B. Turchiano,  J.B. Zhang, “Supervisory control of mobile sensor networks: math formulation, simulation, implementation,” IEEE Transactions on Systems, Man and Cybernetics, Part B, Volume 36,  Issue 4,  Aug. 2006 Page(s):806 - 819

V. Giordano, F.L. Lewis, P. Ballal, and B. Turchiano, “Supervisory controller for task management and resource dispatching in mobile wireless sensor networks,” in Cutting Edge Robotics, ed. V. Kordic, 2005.

P. Ballal, "Structure and decision in mobile wireless sensor networks", MS Thesis, University of Texas at Arlington, Gradworks.Umi.com, 2005.
 

Peer Reviewed Conferences/ Magazines:

P. Ballal., F. Lewis., "Matrix Formulation for Dempster-Shafer Evidence Computations: Application in Free-Choice Petri Nets for Intelligent Diagnostics," Proceedings of Workshop on Petri Nets and Agile Manufacturing, 29th International Conference on Application and Theory of Petri Nets and Other Models of Concurrency Xi’an, China, June, 2008

C. Kwan, J. Yin, X. Liu., A. Athamneh., P. Ballal., A. Ramani., Lee W., F. Lewis., "Conditioned Based Maintenance Using Wireless Sensor Network," submitted to International Conference on Prognostics and Health Management, 2008.

P. Ballal., F. Lewis., "Trust-Based Collaborative Control for Teams in Communication Networks," submitted to Army Science Conference, 2008.