1. Full name: Pham Duy Hung                                                   2. Sex: Male     

3. Date of birth: 02/10/1980                                                        4. Place of birth: Hanoi 

5. Admission decision number: 3205/QĐ-SĐH     Dated: 18/11/2010       

6. Changes in academic process: No                

7. Official thesis title: Developing Self-Deployment Algorithms for Multi-Robot Systems in Unknown Environments          

8. Major: Electronics Engineering                                              9. Code: 9510302.01     

10. Supervisors:

- Assoc. Prof. Dr. Tran Quang Vinh – University of Engineering and Technology

- Assoc. Prof. Dr. Ngo Trung Dung – University of Prince Edward Island, Canada

11. Summary of the new findings of the thesis: The thesis addressed a novel method named hierarchical distributed control for global network integrity preservation of large-scale multi-robot system. The hierarchical distributed control is applied for self-deployment strategies of multi-robot systems for exploration, multi-target tracking, and coverage. The contributions of the thesis are claimed as follows:

- A novel hierarchical distributed control (HDC) for global network integrity preservation of networked multi-robot system. HDC consists of distributed node control for mobility control and global network integrity preservation, and distributed connectivity control for network coverage expansion. HDC is based on a geometric approach considering local connectivity topology among robots so it does not require estimation of algebraic connectivity – the classical method. In addition, thanks to the local connectivity topology minimization, HDC is capable of releasing mobility constraints of local topologies - similar to local minima, therefore, enables a multi-robot system to achieve high performances in terms of swarm movement, multi-target tracking, and coverage.

- HDC is applied for self-deployment strategies for multi-target tracking (MTT) and coverage of networked multi-robot system in an unknown environment. MTT combines the task allocation procedure based on information exchange between robots and the HDC for task performance. Beyond other existing works, we found out that multi-target tracking and coverage problem have common properties: targets for a multi-target tracking problem is similar to virtual targets of a coverage problem, so MTT is applied to solve both problems. In coverage problem, we proposed Virtual Target Generation (VTG) based on topology of hexagonal lattices enabling a multi-robot system to cover structured environment. We examined and evaluate MTT both simulations and real-world experiments.

- A distributed boundary detection and classification algorithm with a novel boundary error correction algorithm based on the geometric approach is proposed in this thesis. This algorithm removes boundary errors without recursive process and global synchronization. We integrated this algorithm in MTT to solve the multi-target tracking problem with non-interconnected targets scenarios.

12. Practical applicability, if any: It has potential applications as patrol and surveillance, search and rescue, transportation in several daily-life settings including warehouses, airport, large manufacturing.

13. Further research directions, if any: (1) Investigate a probability model of sensing and communication capacity for HDC; (2) Deep learning in path planing and navigation using HDC. 

14. Thesis-related publications:  

(1) Pham Duy Hung, Pham Minh Trien, Tran Quang Vinh, and Ngo Trung Dung, "Accelerating multi-target tracking by a swarm of mobile robots with network preservation", IEEE International Conference of Soft Computing and Pattern Recognition (SoCPaR), Hanoi, Vietnam, 2013, pp.327-332.

(2) Pham Duy Hung, Pham Minh Trien, Tran Quang Vinh, and Ngo Trung Dung, "Self-deployment strategy for a swarm of robots with global network preservation to assist rescuers in hazardous environments", IEEE International Conference on Robotics and Biomimetics (ROBIO), Bali, Indonesia, Dec 2014, pp.2655-2660.

(3) Ngo Trung Dung, Pham Duy Hung, and Pham Minh Trien, "A kangaroo inspired heterogeneous swarm of mobile robots with global network integrity for fast deployment and exploration in large scale structured environments", IEEE International Conference on Robotics and Biomimetics (ROBIO), Bali, Indonesia, Dec 2014, pp. 1205-1212.

(4) Pham Duy Hung, Tran Quang Vinh, and Ngo Trung Dung, "A scalable, decentralised large-scale network of mobile robots for multi-target tracking", In: Intelligent Autonomous Systems 13, 2194-5357, vol. 302, Springer International Publishing, pp. 621-637, 2016, ISBN 978-3-319-08338-4.

(5) Pham Duy Hung, Tran Quang Vinh, and Ngo Trung Dung, "Distributed coverage control for networked multi-robot systems in any environments", IEEE International Conference on Advanced Intelligent Mechatronics (AIM), Banff, Canada, 2016, pp. 1067-1072.

(6) Pham Duy Hung, Tran Quang Vinh, and Ngo Trung Dung, "An online local boundary detection and classification algorithm for networked multi-robot systems", IEEE International Conference on Advanced Technologies for Communications (ATC), Hanoi, Vietnam, 2016, pp. 253-258.

(7) Pham Duy Hung, Tran Quang Vinh, and Ngo Trung Dung, "An online distributed boundary detection and classification algorithm for mobile sensor networks", Journal on Electronics and Communications (JEC), Vol. 7, No.1-2 (2017), pp. 29-36.

(8) Pham Duy Hung, Tran Quang Vinh, and Ngo Trung Dung, "Hierarchical distributed control for global network integrity preservation in multi-robot systems", IEEE Transactions on Cybernetics, DOI: 10.1109/TCYB.2019.2913326, 2019, pp. 1-14 (Early Access).