Publications: Refereed Journal Articles

     *  Items in blue are linked to the articles published (in PDF)

             1.   B. Han, C. Gao, X. Zhou, J. Zhang, X. Chen and B. M. Chen, A comprehensive framework for automated facade defect evaluation using deep learning, Submitted for publication.

             2.   K. L. Cheung, G. Yang, C. C. Lee, X. Chen and B. M. Chen, Advancements in civil infrastructure digitization: A review of scan-to-BIM automation methods, technologies, and applications, Submitted for publication.

             3.   X. Zhou, B. Zhao, X. Chen, J. Chen and B. M. Chen, Accurate defects detection with deep global feature fusion and effective activation function, Submitted for publication.

             4.   Z. Pan and B. M. Chen, Cooperative target fencing of multiple double-integrator systems with connectivity preservation, International Journal of Robust and Nonlinear Control, in press.

             5.   B. Zhao, X. Zhou, G. Yang, J. Wen, J. Zhang, J. Dou, G. Li, X. Chen and B. M. Chen, High-resolution infrastructure defect detection dataset sourced by unmanned systems and validated with deep learning approaches, Automation in Construction, in press.

             6.   X. Zhou, L. Li and B. M. Chen, LENet: Lightweight and effective detector for aerial objects, Unmanned Systems, in press.

             7.   X. Zhou, G. Yang, Y. Chen, L. Li and B. M. Chen, VDTNet: A high-performance visual network for detecting and tracking of intruding drones, IEEE Transactions on Intelligent Transportation Systems, in press.

             8.   G. Yang, X. Zhou, C. Gao, X. Chen and B. M. Chen, Learnable cost metric based multi-view stereo for point cloud reconstruction, IEEE Transactions on Industrial Electronics, in press.

             9.   X. Wang, L. Xi, Y. Ding, and B. M. Chen, Distributed encirclement and capture of multiple pursuers with collision avoidance, IEEE Transactions on Industrial Electronics, Vol. 71, No. 7, pp. 7520–7530, July 2024.

         10.   C. Gao, X. Wang, X. Chen and B. M. Chen, A hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction, Control Theory and Technology, in press.

         11.   Q. Li, G. Yang, C. Gao, Y. Huang, J. Zhang, D. Huang, B. Zhao, X. Chen and B. M. Chen, Single drone-based 3D reconstruction approach to improve public engagement in conservation of heritage buildings: A case of Hakka Tulou, Journal of Building Engineering, Vol. 87, Article Number 108954, June 2024.

         12.   P. Zhou and B. M. Chen, Distributed optimal solutions for multiagent pursuit-evasion games for capture and formation control, IEEE Transactions on Industrial Electronics, Vol. 71, No. 5, pp. 5224–5234, May 2024.

         13.   J. Wen, J. Cui, G. Yang, B. Zhao, Y. Zhai, Z. Gao, L. Dou and B. M. Chen, WaterFormer: Global-local transformer for underwater image enhancement with environment adaptor, IEEE Robotics and Automation Magazine, Vol. 31, No. 1, pp. 29–40, March 2024.

         14.   X. Zhao, Z. Gao, H. Li, H. Ji, H. Yang, C. Li, H. Fang and B. M. Chen, How challenging is a challenge? CEMS: A challenge evaluation module for SLAM visual perception, Journal of Intelligent & Robotic Systems, Vol. 110, Article Number 42, March 2024.

         15.   Z. Lin, Z. Gao, B. M. Chen, J. Chen and C. Li, Accurate LiDAR-camera fused odometry and true-color mapping, IEEE Robotics and Automation Letters, Vol. 9, No. 3, pp. 2495–2502, March 2024.

         16.   X. Liu, M. Dou, R. Yan, D. Huang, S. Gao, B. Wang, J. Cui, Q. Ren, L. Dou, Z. Gao, J. Chen and B. M. Chen, TJ-FlyingFish: An unmanned morphable aerial-aquatic vehicle system, Unmanned Systems, Vol. 12, No. 2, pp. 409–428, March 2024.

         17.   Z. Pan and B. M. Chen, Cooperative target fencing of multiple vehicles for a general target with connectivity preservation and collision avoidance, Journal of Systems Science & Complexity, Vol. 37, No. 1, pp. 136–151, February 2024.

         18.   Z. Gao, X. Zhao, M. Cao, Z. Li, K. Liu and B. M. Chen, Synergizing low rank representation and deep learning for automatic pavement crack detection, IEEE Transactions on Intelligent Transportation Systems, Vol. 24, No. 10, pp. 10676–10690, October 2023.

         19.   K. Liu and B. M. Chen, Industrial UAV-based unsupervised domain adaptive crack recognitions: From system setups to real-site infrastructural inspections, IEEE Transactions on Industrial Electronics, Vol. 70, No. 9, pp. 9410–9420, September 2023.

         20.   M. Dou, X. Liu, D. Huang, B. Wang, L. Dou, J. Chen and B. M. Chen, Mathematical modeling of underwater motion for a cross-medium vehicle (in Chinese), Control Engineering of China, Vol. 30, No. 8, pp. 1488 – 1500, August 2023.

         21.   Z. Pan and B. M. Chen, Connectivity-preserving formation tracking for multiple double integrators by a self-tuning adaptive distributed observer, IEEE Control Systems Letters, Vol. 7, pp. 2221–2226, June 2023.

         22.   P. Zhou, S. Lai, J. Cui and B. M. Chen, Formation control of unmanned rotorcraft systems with state constraints and inter-agent collision avoidance, Autonomous Intelligent Systems, Volume 3, Article No. 4 (12 pages), May 2023.

         23.   C. Gao, X. Wang, R. Wang. Z. Zhao, Y. Zhai, X. Chen and B. M. Chen, A UAV-based explore-then-exploit system for autonomous indoor facility inspection and scene reconstruction, Automation in Construction, Vol. 148, Article No. 104753 (14 pages), April 2023.

         24.   P. Zhou and B. M. Chen, Semi-global leader-following output consensus of discrete-time heterogeneous linear systems subject to actuator position and rate saturation, IEEE Transactions on Automatic Control, Vol. 68, No. 2, pp. 1231–1236, February 2023.

         25.   J. Shen, B. Wang, B. M. Chen, R. Bu and B. Jin, Survey of research on wind resistance for quadrotor UAVs, Unmanned Systems, Vol. 11, No. 1, pp. 5–15, January 2023.

         26.   K. Liu, Z. Gao, F. Lin and B. M. Chen, FG-Net: A fast and accurate framework for large-scale LiDAR point cloud understanding, IEEE Transactions on Cybernetics, Vol. 53, No. 1, pp. 553–564, January 2023.

         27.   G. Yang, K. Liu, J. Zhang, B. Zhao, Z. Zhao, X. Chen and B. M. Chen, Datasets and processing methods for boosting visual inspection of civil infrastructure: A comprehensive review and case study on crack classifications, segmentation, and detection, Construction and Building Materials, Vol. 356, Article No. 129226 (25 pages), November 2022.

         28.   Y. Ding, B. Xin, L. Dou, J. Chen and B. M. Chen, A memetic algorithm for curvature-constrained path planning of messenger UAV in air-ground coordination, IEEE Transactions on Automation Science and Engineering, Vol. 19, No. 4, pp. 3735–3749, October 2022.

         29.   P. Zhou and B. M. Chen, Semi-global leader-following output consensus of heterogeneous systems with all agents subject to input saturation, International Journal of Robust and Nonlinear Control, Vol. 32, No. 8, pp. 4648–4664, August 2022.

         30.   Y. Chen, S. Lai, J. Cui, B. Wang and B. M. Chen, GPU-accelerated incremental Euclidean distance transform for online motion planning of mobile robots, IEEE Robotics and Automation Letters, Vol. 7, No. 3, pp. 6894–6901, July 2022.

         31.   P. Zhou and B. M. Chen, Formation-containment control of Euler-Lagrange systems of leaders with bounded unknown inputs, IEEE Transactions on Cybernetics, Vol. 52, No. 7, pp. 6342–6353, July 2022.

         32.   L. Xi, X. Wang, L. Jiao, S. Lai, Z. Peng and B. M. Chen, GTO-MPC-based target chasing using a quadrotor in cluttered environments, IEEE Transactions on Industrial Electronics, Vol. 69, No. 6, pp. 6026–6035, June 2022.

         33.   B. M. Chen, On the trends of autonomous unmanned systems research, Engineering, Vol. 12, pp. 20–23, May 2022.

         34.   P. Zhou and B. M. Chen, Semi-global leader-following consensus-based formation flight of unmanned aerial vehicles, Chinese Journal of Aeronautics, Vol. 35, No. 1, pp. 31–43, January 2022.

         35.   P. Zhou and B. M. Chen, Semi-global leader-following output consensus of heterogeneous systems subject to actuator position and rate saturation, Autonomous Intelligent Systems, Volume 1, Article No. 8 (13 pages), October 2021.

         36.   X. Liu, Z. Gao and B. M. Chen, IPMGAN: Integrating physical model and generative adversarial network for underwater image enhancement, Neurocomputing, Vol. 453, pp. 538–551, September 2021.

         37.   Y. Zhou, S. Lai, H. Cheng, A. H. M. Redhwan, P. Wang, J. Zhu, Z. Gao, Z. Ma, Y. Bi, F. Lin and B. M. Chen, Towards autonomy of micro aerial vehicles in unknown and GPS-denied environments, IEEE Transactions on Industrial Electronics, Vol. 68, No. 8, pp. 7642–7651, August 2021.

         38.   X. Wang, L. Xi, Y. Chen, S. Lai, F. Lin and B. M. Chen, Decentralized MPC-based trajectory generation for multiple quadrotors in cluttered environments, Guidance, Navigation and Control, Vol. 1, Article No. 2150007 (20 pages), July 2021.

         39.   L. Xi, Z. Peng, L. Jiao and B. M. Chen, Smooth trajectory generation of quadrotor for tracking a moving target in cluttered environment, Science China Information Sciences, Vol. 64, Article No. 172209 (16 pages), July 2021.

         40.   Y. H. Tan and B. M. Chen, Survey on the development of aerial-aquatic hybrid vehicles, Unmanned Systems, Vol. 9, No. 3, pp. 263–282, July 2021.

         41.   Y. Lyu, J. Hu, B. M. Chen, C. Zhao and Q. Pan, Multivehicle flocking with collision avoidance via distributed model predictive control, IEEE Transactions on Cybernetics, Vol. 51, No. 5, pp. 2651–2662, May 2021.

         42.   M. Lan, S. Lai, T. H. Lee and B. M. Chen, A survey of motion and task planning techniques for unmanned multicopter systems, Unmanned Systems, Vol. 9, No. 2, pp. 165–198, April 2021.

         43.   X. Liu, Z. Gao and B. M. Chen, MLFcGAN: Multi-level feature fusion based conditional GAN for underwater image color correction, IEEE Geoscience and Remote Sensing Letters, Vol. 17, No. 9, pp. 1488–1492, September 2020.

         44.   Y. H. Tan and B. M. Chen, Thruster allocation and mapping of aerial and aquatic modes for a morphable multimodal quadrotor, IEEE/ASME Transactions on Mechatronics, Vol. 25, No. 4, pp. 2065–2074, August 2020.

         45.   M. Lan, S. Lai and B. M. Chen, Integrated task and motion planning for quadrotors under metric interval temporal logic specifications, Control Theory and Applications, Vol. 36, No. 11, pp. 1952–1964, November 2019.

         46.   S. Lai, M. Lan and B. M. Chen, Model predictive local motion planning with boundary state constrained primitives, IEEE Robotics and Automation Letters, Vol. 4, No. 4, pp. 3577–3584, October 2019.

         47.   Y. Bi, M. Lan, J. Li, S. Lai and B. M. Chen, A lightweight autonomous MAV for indoor search and rescue, Asian Journal of Control, Vol. 21, No. 4, pp. 1732–1744, July 2019.

         48.   S. Lai, M. Lan, K. Gong and B. M. Chen, Axis-coupled trajectory generation for chains of integrators through smoothing splines, Control Theory and Technology, Vol. 17, No. 1, pp. 48–61, February 2019.

         49.   S. Lai, M. Lan, Y. Li and B. M. Chen, Safe navigation of quadrotors with jerk limited trajectories, Frontiers of Information Technology & Electronic Engineering, Vol. 20, No. 1, pp. 107–119, January 2019.

         50.   H. Qin, Y. Bi, F. Lin, Y. F. Zhang and B. M. Chen, A 3D rotating laser-based navigation solution for micro aerial vehicles in dynamic environments, Unmanned Systems, Vol. 6, No. 4, pp. 297–305, December 2018.

         51.   L. Zhang, F. Deng, J. Chen, Y. Bi, S. K. Phang, X. Chen and B. M. Chen, Vision-based target three-dimensional geolocation using unmanned aerial vehicles, IEEE Transactions on Industrial Electronics, Vol. 65, No. 10, pp. 8052–8061, October 2018.

         52.   Y. H. Tan, S. Lai, K. Wang and B. M. Chen, Cooperative control of multiple unmanned aerial systems for heavy duty carrying, Annual Reviews in Control, Vol. 46, pp. 44–57, July 2018.

         53.   L. Wu, Y. Ke and B. M. Chen, Systematic modeling of rotor dynamics for small UAVs, Unmanned Systems, Vol. 6, No. 2, pp. 81–93, June 2018.

         54.   Y. Ke, K. Wang and B. M. Chen, Design and implementation of a hybrid UAV with model-based flight capabilities, IEEE/ASME Transactions on Mechatronics, Vol. 23, No. 3, pp. 1114–1125, June 2018.

         55.   K. Z. Y. Ang, X. Dong, W. Liu, G. Qin, S. Lai, K. Wang, D. Wei, S. Zhang, S. K. Phang, X. Chen, M. Lao, Z. Yang, D. Jia, F. Lin, L. Xie and B. M. Chen, High-precision multi-UAV teaming for the first outdoor night show in Singapore, Unmanned Systems, Vol. 6, No. 1, pp. 39–65, March 2018.

         56.   K. Peng, F. Lin and B. M. Chen, Online schedule for autonomy of multiple unmanned aerial vehicles, Science China Information Sciences, Vol. 60, Article No. 072203 (13 pages), July 2017.

         57.   K. Wang, Y. Ke and B. M. Chen, Autonomous reconfigurable hybrid tail-sitter UAV U-Lion, Science China Information Sciences, Vol. 60, Article No. 033201 (16 pages), March 2017.

         58.   J. Q. Cui, S. Lai, X. Dong and B. M. Chen, Autonomous navigation of UAV in foliage environment, Journal of Intelligent and Robotic Systems, Vol. 84, No. 1, pp. 259–276, December 2016.

         59.   Y. Liu, K. Peng, Y. Lu and B. M. Chen, Flight control law using composite nonlinear feedback technique for a Mars airplane, Journal of Guidance, Control, and Dynamics, Vol. 39, No. 9, pp. 2194–2204, September 2016.

         60.   S. Lai, K. Wang, H. Qin, J. Q. Cui and B. M. Chen, A robust online path planning approach in cluttered environments for micro rotorcraft drones, Control Theory and Technology, Vol. 14, No. 1, pp. 83–96, February 2016.

         61.   S. Zhao, F. Lin, K. Peng, X. Dong, B. M. Chen and T. H. Lee, Vision-aided estimation of attitude, velocity, and inertial measurement bias for UAV stabilization, Journal of Intelligent and Robotic Systems, Vol. 81, pp. 531–549, March 2016.

         62.   J. Q. Cui, S. K. Phang, K. Z. Y. Ang, F. Wang, X. Dong, Y. Ke, S. Lai, K. Li, X. Li, J. Lin, P. Liu, T. Pang, K. Wang, Z. Yang, F. Lin and B. M. Chen, Cooperative search and rescue using multiple drones in post-disaster situation, Unmanned Systems, Vol. 4, No. 1, pp. 83–96, February 2016.

         63.   S. K. Phang, S. Lai, F. Wang, M. Lan and B. M. Chen, Systems design and implementation with jerk-optimized trajectory generation for UAV calligraphy, Mechatronics, Vol. 30, pp. 65–75, September 2015.

         64.   L. Bai, S. Yan, X. Zheng and B. M. Chen, Market turning points forecasting using wavelet analysis, Physica A: Statistical Mechanics and its Applications, Vol. 437, pp. 184–197, May 2015.

         65.   K. Z. Y. Ang, J. Cui, T. Pang, K. Li, K. Wang, Y. Ke and B. M. Chen, Design and implementation of a thrust-vectored unmanned tail-sitter with reconfigurable wings, Unmanned Systems, Vol. 3, No. 2, pp. 143–162, April 2015.

         66.   S. Zhao, Z. Hu, M. Yin, K. Z. Y. Ang, P. Liu, F. Wang, X. Dong, F. Lin, B. M. Chen and T. H. Lee, A robust real-time vision system for autonomous cargo transfer by an unmanned helicopter, IEEE Transactions on Industrial Electronics, Vol. 62, No. 2, pp. 1210–1219, February 2015.

         67.   F. Wang, P. Liu, S. Zhao, B. M. Chen, S. K. Phang, S. Lai, T. Pang, B. Wang, C. Cai and T. H. Lee, Development of an unmanned helicopter for vertical replenishment, Unmanned Systems, Vol. 3, No. 1, pp. 63–87, January 2015.

         68.   A. Karimoddini, H. Lin, B. M. Chen and T. H. Lee, Hierarchical hybrid modeling and control of an unmanned helicopter, International Journal of Control, Vol. 87, No. 9, pp. 1779–1793, September 2014.

         69.   X. Zheng and B. M. Chen, Identification of stock market forces in the system adaptation framework, Information Sciences, Vol. 265, pp. 105–122, May 2014.

         70.   S. K. Phang, K. Li, K. H. Yu, B. M. Chen and T. H. Lee, Systematic design and implementation of a micro unmanned quadrotor system, Unmanned Systems, Vol. 2, No. 2, pp. 121–141, April 2014.

         71.   S. Zhao, F. Lin, K. Peng, B. M. Chen and T. H. Lee, Finite-time stabilization of cyclic formations using bearing-only measurements, International Journal of Control, Vol. 87, No. 4, pp. 715–727, April 2014.

         72.   S. Zhao, B. M. Chen and T. H. Lee, Optimal deployment of mobile sensors for target tracking in 2D and 3D spaces, IEEE/CAA Journal of Automatica Sinica, Vol. 1, No. 1, pp. 24–30, January 2014.

         73.   Y. Sun, H. Lin and B. M. Chen, Bisimilarity enforcing supervisory control for deterministic specifications, Automatica, Vol. 50, No. 1, pp. 287–290, January 2014.

         74.   S. Zhao, F. Lin, K. Peng, B. M. Chen and T. H. Lee, Distributed control of angle-constrained circular formation using bearing-only measurements, Systems & Control Letters, Vol. 63, No. 1, pp. 12–24, January 2014.

         75.   G. Cheng, K. Peng, B. M. Chen and T. H. Lee, Discrete-time mode switching control with application to a PMSM position servo system, Mechatronics, Vol. 23, No. 8, pp. 1191–1201, December 2013.

         76.   X. Liu, H. Lin and B. M. Chen, Structural controllability of switched linear systems, Automatica, Vol. 49, No. 12, pp. 3531–3537, December 2013.

         77.   R. Chisholm, J. Q. Cui, S. K. Y. Lum and B. M. Chen, UAV LiDAR for below-canopy forest surveys, Journal of Unmanned Vehicle Systems, Vol. 1, pp. 61–68, November 2013.

         78.   F. Wang, J. Q. Cui, B. M. Chen and T. H. Lee, A comprehensive UAV indoor navigation system based on vision optical flow and laser FastSLAM, Acta Automatica Sinica, Vol. 39, No. 11, pp. 1889–1900, November 2013.

         79.   F. Lin, K. Z. Y. Ang, F. Wang, B. M. Chen, T. H. Lee, B. Yang, M. Dong, X. Dong, J. Cui, S. K. Phang, B. Wang, D. Luo, K. Peng, G. Cai, S. Zhao, M. Yin and K. Li, Development of an unmanned coaxial rotorcraft for the DARPA UAVForge Challenge, Unmanned Systems, Vol. 1, No. 2, pp. 211–245, October 2013.

         80.   S. Zhao, B. M. Chen and T. H. Lee, Optimal sensor placement for target localization and tracking in 2D and 3D, International Journal of Control, Vol. 86, No. 10, pp. 1687–1704, October 2013.

         81.   M. Zhu, S. Lai, R. Boucher, B. M. Chen, C. Xiang and W. Kang, Minimum time trajectory for helicopter UAVs: computation and flight test, Applied Mathematical Sciences, Vol. 7, No. 130, pp. 6475–6487, September 2013.

         82.   A. Karimoddini, H. Lin, B. M. Chen and T. H. Lee, A bumpless hybrid supervisory control algorithm for the formation of unmanned helicopters, Mechatronics, Vol. 23, No. 6, pp. 677–688, September 2013.

         83.   K. Peng and B. M. Chen, Variant-factor technique for tracking control of a class of nonlinear systems with input saturation, Control and Intelligent Systems, Vol. 41, No. 3, pp. 169–177, July 2013.

         84.   A. Karimoddini, H. Lin, B. M. Chen and T. H. Lee, Hybrid 3-D formation control for unmanned helicopters, Automatica, Vol. 49, No. 2, pp. 424–433, February 2013.

         85.   X. Liu, H. Lin and B. M. Chen, Graph-theoretic characterisations of structural controllability for multi-agent system with switching topology, International Journal of Control, Vol. 86, No. 2, pp. 222–231, February 2013.

         86.   G. Cai, B. Wang, B. M. Chen and T. H. Lee, Design and implementation of a flight control system for an unmanned rotorcraft using RPT control approach, Asian Journal of Control, Vol. 15, No. 1, pp. 95–119, January 2013.

         87.   Y. Sun, H. Lin and B. M. Chen, An input-output simulation approach to controlling multi-affine systems for linear temporal logic specifications, International Journal of Control, Vol. 85, No. 10, pp. 1464–1476, October 2012.

         88.   X. Zheng and B. M. Chen, Modeling and forecasting of stock markets under a system adaptation framework, Journal of Systems Science and Complexity, Vol. 25, No. 4, pp. 641–674, September 2012.

         89.   F. Lin, X. Dong, B. M. Chen, K. Y. Lum and T. H. Lee, A robust real-time embedded vision system on an unmanned rotorcraft for ground target following, IEEE Transactions on Industrial Electronics, Vol. 59, No. 2, pp. 1038–1049, February 2012.

         90.   G. Cai, B. M. Chen, T. H. Lee and K. Y. Lum, Comprehensive nonlinear modeling of a miniature unmanned helicopter, Journal of the American Helicopter Society, Vol. 57, No. 1, pp. 012004-1~13, January 2012.

         91.   F. Wang, S. K. Phang, J. J. Ong, B. M. Chen and T. H. Lee, Design and construction methodology of an indoor UAV system with embedded vision, Control and Intelligent Systems, Vol. 40, No. 1, pp. 22–32, January 2012.

         92.   B. Yun, G. Cai, B. M. Chen, K. Peng and K. Y. Lum, GPS signal enhancement and attitude determination for a mini and low-cost unmanned aerial vehicle, Transactions of the Institute of Measurement and Control, Vol. 33, No. 6, pp. 665–682, August 2011.

         93.   A. Karimoddini, H. Lin, B. M. Chen and T. H. Lee, Hybrid formation control of the autonomous helicopters, Mechatronics, Vol. 21, No. 5, pp. 886–898, August 2011.

         94.   G. Cai, B. M. Chen, X. Dong and T. H. Lee, Design and implementation of a robust and nonlinear flight control system for an unmanned helicopter, Mechatronics, Vol. 21, No. 5, pp. 803–820, August 2011.

         95.   X. Liu, H. Lin and B. M. Chen, Null controllability of planar bimodal piecewise linear systems, International Journal of Control, Vol. 84, No. 4, pp. 766–782, April 2011.

         96.   X. Dong, B. M. Chen, G. Cai, H. Lin and T. H. Lee, A comprehensive real-time software system for flight coordination and cooperative control of multiple unmanned aerial vehicles, International Journal of Robotics and Automation, Vol. 26, No. 1, pp. 49–63, February 2011.

         97.   G. Cheng, B. M. Chen, K. Peng and T. H. Lee, A MATLAB toolkit for composite nonlinear feedback control – improving transient response in tracking control, Journal of Control Theory and Applications, Vol. 8, No. 3, pp. 271–279, August 2010.

         98.   W. Lan, C. K. Thum and B. M. Chen, A hard disk drive servo system design using composite nonlinear feedback control with optimal nonlinear gain tuning methods, IEEE Transactions on Industrial Electronics, Vol. 57, No. 5, pp. 1735–1745, May 2010.

         99.   C. K. Thum, C. Du, B. M. Chen, E. H. Ong and K. P. Tan, A unified control scheme for combined seeking and track-following of a hard disk drive servo system, IEEE Transactions on Control Systems Technology, Vol. 18, No. 2, pp. 294–306, March 2010.

      100.   G. Cai, B. M. Chen and T. H. Lee, An overview on development of miniature unmanned rotorcraft systems, Frontiers of Electrical and Electronic Engineering in China, Vol. 5, No. 1, pp. 1–14, March 2010.

      101.   B. Yun, B. M. Chen, K. Y. Lum and T. H. Lee, Design and implementation of a leader-follower formation flight control system for unmanned helicopters, Journal of Control Theory and Applications, Vol. 8, No. 1, pp. 61–68, February 2010.

      102.   C. K. Thum, C. Du, F. L. Lewis, B. M. Chen and E. H. Ong, H∞ disturbance observer design for high precision track-following in hard disk drives, IET Control Theory & Applications, Vol. 3, No. 12, pp. 1591–1598, December 2009.

      103.   F. Lin, K. Y. Lum, B. M. Chen and T. H. Lee, Development of a vision-based ground target detection and tracking system for a small unmanned helicopter, Science in China – Series F: Information Sciences, Vol. 52, No. 11, pp. 2201–2215, November 2009.

      104.   C. K. Pang, Y. Lu, C. Chen, J. Chen, H. Zhu, J. Yang, J. Mou, G. Guo, B. M. Chen and T. H. Lee, Design, fabrication, sensor fusion, and control of a micro X-Y stage media platform for probe-based storage systems, Mechatronics, Vol. 19, No. 7, pp. 1158–1168, October 2009.

      105.   G. Cai, B. M. Chen, T. H. Lee and M. Dong, Design and implementation of a hardware-in-the-loop simulation system for small-scale UAV helicopters, Mechatronics, Vol. 19, No. 7, pp. 1057–1066, October 2009.

      106.   C. K. Pang, S. C. Tam, G. Guo, B. M. Chen, F. L. Lewis, T. H. Lee and C. Du, Improved disturbance rejection with online adaptive pole-zero compensation on a Φ-shaped PZT active suspension, Microsystem Technologies, Vol. 15, Nos. 10-11, pp. 1499–1508, October 2009.

      107.   K. Peng, G. Cai, B. M. Chen, M. Dong, K. Y. Lum and T. H. Lee, Design and implementation of an autonomous flight control law for a UAV helicopter, Automatica, Vol. 45, No. 10, pp. 2333–2338, October 2009.

      108.   X. Liu, Z. Lin and B. M. Chen, Assignment of complete structural properties of linear systems via sensor selection, IEEE Transactions on Automatic Control, Vol. 54, No. 9, pp. 2072–2086, September 2009.

      109.   J. Gadewadikar, F. L. Lewis, K. Subbarao, K. Peng and B. M. Chen, H-infinity static output-feedback control for rotorcraft, Journal of Intelligent and Robotic Systems, Vol. 54, No. 4, pp. 629–646, April 2009.

      110.   C. K. Thum, C. Du, B. M. Chen, E. H. Ong and K. P. Tan, Midfrequency runout compensation in hard disk drives via a time-varying group filtering scheme, IEEE Transactions on Magnetics, Vol. 44, No. 12, pp. 4769–4779, December 2008.

      111.   G. Cai, F. Lin, B. M. Chen and T. H. Lee, Systematic design methodology and construction of UAV helicopters, Mechatronics, Vol. 18, No. 10, pp. 545–558, December 2008.

      112.   G. Cai, B. M. Chen, K. Peng, M. Dong and T. H. Lee, Comprehensive modeling and control of the yaw channel of a UAV helicopter, IEEE Transactions on Industrial Electronics, Vol. 55, No. 9, pp. 3426–3434, September 2008.

      113.   C. K. Thum, C. Du, J. Zhang, K. P. Tan, B. M. Chen and E. H. Ong, Servo control design for a high TPI servo track writer with microactuators, IEEE Transactions on Magnetics, Vol. 44, No. 9, pp. 2227–2234, September 2008.

      114.   W. Lan, B. M. Chen and F. L. Lewis, Explicit constructions of global stabilization and nonlinear H∞ control laws for a class of nonminimum phase nonlinear multivariable systems, International Journal of Robust and Nonlinear Control, Vol. 18, No. 12, pp. 1257–1284, August 2008.

      115.   J. Gadewadikar, F. L. Lewis, K. Subbarao and B. M. Chen, Structured H∞ command and control loop design for unmanned helicopters, AIAA Journal of Guidance, Control and Dynamics, Vol. 31, No. 4, pp. 1093–1102, July-August 2008.

      116.   W. Lan and B. M. Chen, Explicit constructions of global stabilization and nonlinear H∞ control laws for a class of nonminimum phase nonlinear systems, Automatica, Vol. 44, No. 3, pp. 738–744, March 2008.

      117.   B. M. Chen, X. Liu and Z. Lin, Interconnection of Kronecker canonical form and special coordinate basis of multivariable linear systems, Systems & Control Letters, Vol. 57, No. 1, pp. 28–33, January 2008.

      118.   X. Liu, Z. Lin and B. M. Chen, Further results on structural assignment of linear systems via sensor selection, Automatica, Vol. 43, No. 9, pp. 1631–1639, September 2007.

      119.   M. Dong, B. M. Chen, G. Cai and K. Peng, Development of a real-time onboard and ground station software system for a UAV helicopter, AIAA Journal of Aerospace Computing, Information, and Communication, Vol. 4, No. 8, pp. 933–955, August 2007.

      120.   Y. He, B. M. Chen and W. Lan, On improving transient performance in tracking control for a class of nonlinear discrete-time systems with input saturation, IEEE Transactions on Automatic Control, Vol. 52, No. 7, pp. 1307–1313, July 2007.

      121.   M. He, B. M. Chen and Z. Lin, Structural decomposition and its properties of linear multivariable singular systems, Journal of Systems Science and Complexity, Vol. 20, No. 2, pp. 198–214, June 2007.

      122.   C. K. Pang, F. L. Lewis, S. S. Ge, G. Guo, B. M. Chen and T. H. Lee, Singular perturbation control for vibration rejection in HDDs using a PZT active suspension as fast subsystem observer, IEEE Transactions on Industrial Electronics, Vol. 54, No. 3, pp. 1375–1386, June 2007.

      123.   C. K. Pang, G. Guo, B. M. Chen and T. H. Lee, Enhanced disturbance suppression in sampled-data systems and its application to high density data storage servos, Microsystem Technologies, Vol. 13, Nos. 8-10, pp. 911–921, May 2007.

      124.   C. K. Pang, W. E. Wong, G. Guo, B. M. Chen and T. H. Lee, Nonrepeatable run-out rejection using online iterative control for high-density storage, IEEE Transactions on Magnetics, Vol. 43, No. 5, pp. 2029–2037, May 2007.

      125.   G. Cheng, K. Peng, B. M. Chen and T. H. Lee, Improving transient performance in tracking general references using composite nonlinear feedback control and its application to XY-table positioning mechanism, IEEE Transactions on Industrial Electronics, Vol. 54, No. 2, pp. 1039–1051, April 2007.

      126.   K. Peng, G. Cheng, B. M. Chen and T. H. Lee, Improvement of transient performance in tracking control for discrete-time systems with input saturation and disturbances, IET Control Theory & Applications, Vol. 1, No. 1, pp. 65–74, January 2007.

      127.   Y. He, B. M. Chen and C. Wu, Improving transient performance in tracking control for linear multivariable discrete-time systems with input saturation, Systems & Control Letters, Vol. 56, No. 1, pp. 25–33, January 2007.

      128.   X. Liu, Z. Lin and B. M. Chen, Symbolic realization of asymptotic time-scale and eigenstructure assignment design method in multivariable control, International Journal of Control, Vol. 79, No. 11, pp. 1471–1484, November 2006.

      129.   S. Lu, B. M. Chen and C. C. Ko, A partition approach for the restoration of camera images of planar and curled document, Image and Vision Computing, Vol. 24, No. 8, pp. 837–848, August 2006.

      130.   C. K. Pang, G. Guo, B. M. Chen and T. H. Lee, Self-sensing actuator for nanopositioning and active damping in dual-stage HDDs, IEEE/ASME Transactions on Mechatronics, Vol. 11, No. 3, pp. 328–338, June 2006.

      131.   W. Lan, B. M. Chen and Z. Ding, Adaptive estimation and rejection of unknown sinusoidal disturbances through measurement feedback for a class of nonminimum phase nonlinear MIMO systems, International Journal of Adaptive Control and Signal Processing, Vol. 20, No. 2, pp. 77–97, March 2006.

      132.   W. Lan, B. M. Chen and Y. He, On improvement of transient performance in tracking control for a class of nonlinear systems with input saturation, Systems & Control Letters, Vol. 55, No. 2, pp. 132–138, February 2006.

      133.   C. C. Ko, B. M. Chen, J. P. Chen, J. Zhang and K. C. Tan, A web-based laboratory on control of a two-degree-of-freedom helicopter, International Journal of Engineering Education, Vol. 21, No. 6, pp. 1017–1030, November 2005.

      134.   G. Cheng, K. Peng, B. M. Chen and T. H. Lee, A microdrive track following controller design using robust and perfect tracking control with nonlinear compensation, Mechatronics, Vol. 15, No. 8, pp. 933–948, October 2005.

      135.   K. Peng, B. M. Chen, G. Cheng and T. H. Lee, Modeling and compensation of nonlinearities and friction in a micro hard disk drive servo system with nonlinear feedback control, IEEE Transactions on Control Systems Technology, Vol. 13, No. 5, pp. 708–721, September 2005.

      136.   X. Liu, B. M. Chen and Z. Lin, Linear systems toolkit in MATLAB: Structural decompositions and their applications, Journal of Control Theory & Applications, Vol. 3, No. 3, pp. 287–294, August 2005.

      137.   Y. He, B. M. Chen and C. Wu, Composite nonlinear control with state and measurement feedback for general multivariable systems with input saturation, Systems & Control Letters, Vol. 54, No. 5, pp. 455–469, May 2005.

      138.   S. Lu, B. M. Chen and C. C. Ko, Perspective rectification of document images using fuzzy set and morphological operations, Image and Vision Computing, Vol. 23, No. 5, pp. 541–553, May 2005.

      139.   K. Peng, B. M. Chen, G. Cheng and T. H. Lee, Friction and nonlinearity compensation in hard disk drive servo systems using robust composite nonlinear feedback control, Australian Journal of Electrical & Electronics Engineering, Vol. 2, No. 1, pp. 81–90, January 2005.

      140.   K. Peng, B. M. Chen, T. H. Lee and V. Venkataramanan, Design and implementation of a dual-stage actuated HDD servo system via composite nonlinear control approach, Mechatronics, Vol. 14, No. 9, pp. 965–988, September 2004.

      141.   Y.-Y. Cao, Z. Lin and B. M. Chen, An output feedback H∞ controller design for linear systems subject to sensor nonlinearities, IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, Vol. 50, No. 7, pp. 914–921, July 2003.

      142.   B. M. Chen, T. H. Lee, K. Peng and V. Venkataramanan, Composite nonlinear feedback control for linear systems with input saturation: Theory and an application, IEEE Transactions on Automatic Control, Vol. 48, No. 3, pp. 427–439, March 2003.

      143.   X. Liu, B. M. Chen and Z. Lin, On the problem of general structural assignments of linear systems through sensor/actuator selection, Automatica, Vol. 39, No. 2, pp. 233–241, February 2003.

      144.   V. Venkataramanan, K. Peng, B. M. Chen and T. H. Lee, Discrete-time composite nonlinear feedback control with an application in design of a hard disk drive servo system, IEEE Transactions on Control Systems Technology, Vol. 11, No. 1, pp. 16–23, January 2003.

      145.   M. He and B. M. Chen, Structural decomposition of linear singular systems: The single-input and single-output case, Systems & Control Letters, Vol. 47, No. 4, pp. 327–334, November 2002.

      146.   V. Venkataramanan, B. M. Chen, T. H. Lee and G. Guo, A new approach to the design of mode switching control in hard disk drive servo systems, Control Engineering Practice, Vol. 10, No. 9, pp. 925–939, September 2002.

      147.   T. Hu, Z. Lin and B. M. Chen, Analysis and design for linear discrete-time systems subject to actuator saturation and disturbance, Systems & Control Letters, Vol. 45, No. 2, pp. 97–112, February 2002.

      148.   T. Hu, Z. Lin and B. M. Chen, An analysis and design method for linear systems subject to actuator saturation and disturbance, Automatica, Vol. 38, No. 2, pp. 351–359, February 2002.

      149.   B. M. Chen, Z. Lin and K. Liu, Robust and perfect tracking of discrete-time systems, Automatica, Vol. 38, No. 2, pp. 293–299, February 2002.

      150.   C. C. Ko, B. M. Chen, S. Y. Hu, V. Ramakrishnan, C. D. Cheng, Y. Zhuang and J. Chen, A web-based virtual laboratory on a frequency modulation experiment, IEEE Transactions on Systems, Man, and Cybernetics, Part C: Applications and Reviews, Vol. 31, No. 3, pp. 295–303, August 2001.

      151.   Z. Li, G. Guo, B. M. Chen and T. H. Lee, Optimal control design to achieve highest track-per-inch in hard disk drives, Journal of Information Storage and Processing Systems, Vol. 3, pp. 27–41, April 2001.

      152.   T. B. Goh, Z. Li, B. M. Chen, T. H. Lee and T. Huang, Design and implementation of a hard disk drive servo system using robust and perfect tracking approach, IEEE Transactions on Control Systems Technology, Vol. 9, No. 2, pp. 221–233, March 2001.

      153.   C. C. Ko, B. M. Chen, J. Chen, Y. Zhuang and K. C. Tan, Development of a web-based laboratory for control experiments on a coupled tank apparatus, IEEE Transactions on Education, Vol. 44, No. 1, pp. 76–86, February 2001.

      154.   K. Liu, B. M. Chen and Z. Lin, On the problem of robust and perfect tracking for linear systems with external disturbances, International Journal of Control, Vol. 74, No. 2, pp. 158–174, January 2001.

      155.   B. M. Chen, I. M. Y. Mareels, Y. F. Zheng and C. Zhang, Solutions to disturbance decoupling problem with constant measurement feedback for linear systems, Automatica, Vol. 36, No. 11, pp. 1717–1724, November 2000.

      156.   Z. Lin and B. M. Chen, Solutions to general H∞ almost disturbance decoupling problem with measurement feedback and internal stability for discrete-time systems, Automatica, Vol. 36, No. 8, pp. 1103–1122, August 2000.

      157.   B. M. Chen, K. Liu and Z. Lin, Solvability conditions and solutions to perfect regulation problem under measurement output feedback, Systems & Control Letters, Vol. 40, No. 4, pp. 269–277, July 2000.

      158.   C. C. Ko, B. M. Chen, S. H. Chen, V. Ramakrishnan, R. Chen, S. Y. Hu and Y. Zhuang, A large scale web-based virtual oscilloscope laboratory experiment, Engineering Science and Education Journal, Vol. 9, No. 2, pp. 69–76, April 2000.

      159.   B. C. Siew, B. M. Chen and T. H. Lee, Design and implementation of a robust controller for a free gyro-stabilized mirror system, ASME Transactions – Journal of Dynamic Systems, Measurement, and Control, Vol. 121, No. 3, pp. 550–556, September 1999.

      160.   Z. Lin, X. Bao and B. M. Chen, Further results on almost disturbance decoupling with global asymptotic stability for nonlinear systems, Automatica, Vol. 35, No. 4, pp. 709–717, April 1999.

      161.   B. M. Chen, T. H. Lee, C. C. Hang, Y. Guo and S. Weerasooriya, An H∞ almost disturbance decoupling robust controller design for a piezoelectric bimorph actuator with hysteresis, IEEE Transactions on Control Systems Technology, Vol. 7, No. 2, pp. 160–174, March 1999.

      162.   B. M. Chen, J. He and Y.-L. Chen, Explicit solvability conditions for general discrete-time H∞ almost disturbance decoupling problem with internal stability, International Journal of Systems Science, Vol. 30, No. 1, pp. 105–115, January 1999.

      163.   B. M. Chen, Direct computation of infimum in discrete-time H∞ optimization using measurement feedback, Systems & Control Letters, Vol. 35, No. 5, pp. 269–278, December 1998.

      164.   B. M. Chen, On properties of the special coordinate basis of linear systems, International Journal of Control, Vol. 71, No. 6, pp. 981–1003, December 1998.

      165.   B. M. Chen, Z. Lin and C. C. Hang, Design for general H∞ almost disturbance decoupling problem with measurement feedback and internal stability – An eigenstructure assignment approach, International Journal of Control, Vol. 71, No. 4, pp. 653–685, November 1998.

      166.   Z. Lin, B. M. Chen, A. Saberi and U. Ly, Simultaneous H2/H∞ optimal control for discrete-time systems: The state feedback case, Journal of Control Theory & Applications, Vol. 15, No. 2, pp. 217–225, April 1998.

      167.   B. M. Chen and S. R. Weller, Mappings of the finite and infinite zero structures and invertibility structures of general linear multivariable systems under the bilinear transformation, Automatica, Vol. 34, No. 1, pp. 111–124, January 1998.

      168.   B. M. Chen, Exact computation of infimum for a class of continuous-time H∞ optimal control problem with a nonzero direct feedthrough term from the disturbance input to the controlled output, Systems & Control Letters, Vol. 32, No. 2, pp. 99–109, November 1997.

      169.   B. M. Chen, Solvability conditions for the disturbance decoupling problems with static measurement feedback, International Journal of Control, Vol. 68, No. 1, pp. 51–60, November 1997.

      170.   B. M. Chen, A. Saberi and Y. Shamash, Necessary and sufficient conditions under which a discrete time H2-optimal control problem has a unique solution, Journal of Control Theory & Applications, Vol. 13, No. 6, pp. 745–753, December 1996.

      171.   Z. Lin, B. M. Chen, A. Saberi and Y. Shamash, Inner-outer factorization of discrete-time transfer matrices, IEEE Transactions on Circuits and Systems – I: Fundamental Theory and Applications, Vol. 43, No. 11, pp. 941–945, November 1996.

      172.   B. M. Chen, Y. Guo and Z. Lin, Non-iterative computation of infimum in discrete-time H∞ optimization and solvability conditions for the discrete-time disturbance decoupling problem, International Journal of Control, Vol. 65, No. 3, pp. 433–454, October 1996.

      173.   B. M. Chen and Y.-L. Chen, Loop transfer recovery design via new observer based and CSS architecture based controllers, International Journal of Robust and Nonlinear Control, Vol. 5, No. 7, pp. 649–669, November 1995.

      174.   B. M. Chen and D. Z. Zheng, Simultaneous finite and infinite zero assignments of linear systems, Automatica, Vol. 31, No. 4, pp. 643–648, April 1995.

      175.   B. M. Chen, A simple algorithm for the stable/unstable decomposition of a linear discrete-time system, International Journal of Control, Vol. 61, No. 1, pp. 255–260, January 1995.

      176.   B. M. Chen, A. Saberi, Y. Shamash and P. Sannuti, Construction and parameterization of all static and dynamic H2-optimal state feedback solutions for discrete time systems, Automatica, Vol. 30, No. 10, pp. 1617–1624, October 1994.

      177.   A. A. Stoorvogel, A. Saberi and B. M. Chen, The discrete-time H∞ control problem with strictly proper measurement feedback, IEEE Transactions on Automatic Control, Vol. 39, No. 9, pp. 1936–1939, September 1994.

      178.   A. Saberi, B. M. Chen and Z. Lin, Closed-form solutions to a class of H∞ optimization problem, International Journal of Control, Vol. 60, No. 1, pp. 41–70, July 1994.

      179.   B. M. Chen, A. Saberi and Y. Shamash, A non-recursive method for solving the general discrete time algebraic Riccati equation related to the H∞ control problem, International Journal of Robust and Nonlinear Control, Vol. 4, No. 4, pp. 503–519, July-August 1994.

      180.   A. A. Stoorvogel, A. Saberi and B. M. Chen, The discrete-time H∞ control problem with measurement feedback, International Journal of Robust and Nonlinear Control, Vol. 4, No. 4, pp. 457–479, July-August 1994.

      181.   A. A. Stoorvogel, A. Saberi and B. M. Chen, A reduced order observer based controller design for H∞ optimization, IEEE Transactions on Automatic Control, Vol. 39, No. 2, pp. 355–360, February 1994.

      182.   A. Saberi, B. M. Chen, P. Sannuti and U. Ly, Simultaneous H2/H∞ optimal control: The state feedback case, Automatica, Vol. 29, No. 6, pp. 1611–1614, November 1993.

      183.   A. A. Stoorvogel, A. Saberi and B. M. Chen, Full and reduced order observer based controller design for H2-optimization, International Journal of Control, Vol. 58, No. 4, pp. 803–834, October 1993.

      184.   B. M. Chen and A. Saberi, Noniterative computation of infimum in H∞ optimisation for plants with invariant zeros on the jw axis, IEE Proceedings-Part D: Control Theory and Applications, Vol. 140, No. 5, pp. 298–304, September 1993.

      185.   B. M. Chen and A. Saberi, Necessary and sufficient conditions under which an H2-optimal control problem has a unique solution, International Journal of Control, Vol. 58, No. 2, pp. 337–348, August 1993.

      186.   A. A. Stoorvogel, A. Saberi and B. M. Chen, Characterization of all closed loop transfer function matrices in H∞ optimization, Control – Theory and Advanced Technology, Vol. 9, No. 2, pp. 565–576, June 1993.

      187.   Z. Lin, B. M. Chen and A. Saberi, Explicit expressions for cascade factorizations of general non-strictly proper systems, Control – Theory and Advanced Technology, Vol. 9, No. 2, pp. 501–515, June 1993.

      188.   B. M. Chen, A. Saberi, P. Sannuti and Y. Shamash, Construction and parameterization of all static and dynamic H2-optimal state feedback solutions, optimal fixed modes and fixed decoupling zeros, IEEE Transactions on Automatic Control, Vol. 38, No. 2, pp. 248–261, February 1993.

      189.   B. M. Chen, A. Saberi and U. Ly, A non-iterative method for computing the infimum in H∞ optimization, International Journal of Control, Vol. 56, No. 6, pp. 1399–1418, December 1992.

      190.   B. M. Chen, A. Saberi and P. Sannuti, On blocking zeros and strong stabilizability of linear multivariable systems, Automatica, Vol. 28, No. 5, pp. 1051–1055, September 1992.

      191.   B. M. Chen, A. Saberi and P. Sannuti, Necessary and sufficient conditions for a nonminimum phase plant to have a recoverable target loop – A stable compensator design for LTR, Automatica, Vol. 28, No. 3, pp. 493–507, May 1992.

      192.   B. M. Chen, A. Saberi and P. Sannuti, Loop transfer recovery for general nonminimum phase non-strictly proper systems; Part 2: Design, Control – Theory and Advanced Technology, Vol. 8, No. 1, pp. 101–144, March 1992.

      193.   B. M. Chen, A. Saberi and P. Sannuti, Loop transfer recovery for general nonminimum phase non-strictly proper systems; Part 1: Analysis, Control – Theory and Advanced Technology, Vol. 8, No. 1, pp. 59–100, March 1992.

      194.   B. M. Chen, A. Saberi and U. Ly, Exact computation of the infimum in H∞ optimization via state feedback, Control – Theory and Advanced Technology, Vol. 8, No. 1, pp. 17–35, March 1992.

      195.   B. M. Chen, A. Saberi and P. Sannuti, Explicit expressions for cascade factorization of general nonminimum phase systems, IEEE Transactions on Automatic Control, Vol. 37, No. 3, pp. 358–363, March 1992.

      196.   B. M. Chen, A. Saberi and U. Ly, Exact computation of the infimum in H∞ optimization via output feedback, IEEE Transactions on Automatic Control, Vol. 37, No. 1, pp. 70–78, January 1992.

      197.   A. Saberi, B. M. Chen and P. Sannuti, Theory of LTR for nonminimum phase systems, recoverable target loops, recovery in a subspace; Part 2: Design, International Journal of Control, Vol. 53, No. 5, pp. 1117–1160, May 1991.

      198.   A. Saberi, B. M. Chen and P. Sannuti, Theory of LTR for nonminimum phase systems, recoverable target loops, recovery in a subspace; Part 1: Analysis, International Journal of Control, Vol. 53, No. 5, pp. 1067–1115, May 1991.

      199.   B. M. Chen, A. Saberi and P. Sannuti, A new stable compensator design for exact and approximate loop transfer recovery, Automatica, Vol. 27, No. 2, pp. 257–280, March 1991.

      200.   B. M. Chen, A. Saberi, S. Bingulac and P. Sannuti, Loop transfer recovery for non-strictly proper plants, Control – Theory and Advanced Technology, Vol. 6, No. 4, pp. 573–594, December 1990.