Education and Work Experience

National University of Singapore , Singapore , October 2007 – present

Research Fellow

Shanghai Jiao Tong University , Shanghai , China , September 1997 – September 2007

PhD, Mechatronics, September 2007

B. Eng., Mechanical Engineering, July 2001 (major)

B. Eng., Computer Science and Engineering, July 2001 (minor)

Research Topics and Interests

Convex geometry and numerical algorithms

•  Presented a fast algorithm for calculating the minimum distance between a point and a convex cone [1,17]. By this algorithm, developed the most efficient method of equilibrium and/or force-closure tests for robotic systems, such as multifingered hands, cable-driven manipulators, and multilegged robots. This algorithm has been also used in contact force distribution for multi-contact robotic systems [2].

•  Proposed a numerical algorithm for determining the intersection point(s) of a compact convex set and a ray [16,19]. Applied this algorithm to solving the problem of contact force optimization.

•  Seeking other applications in robotics research and applications in other fields.

Analysis, planning, and control of walking robots

•  Established a new framework for dynamic analysis of walking robots [18]. Developing new techniques for motion planning under this framework .

•  Pattern generation for various motions of humanoid robots, such as bipedal walking, climbing obstacles, and push recovery [20 – 22].

Fixturing and modular fixture

•  Put forward methods for automated fixture layout design [3,4].

•  Designed a 3-D modular fixture and developed an automatic synthesis algorithm [7].

Grasping and dexterous manipulation

•  Suggested a general method of force-closure analysis by the duality between the infinitesimal motion and the wrench [14]. Gave a systematic and strict derivation of the ray-shooting approach to force-closure problems using the terminology of convex analysis [10,13].

•  Precisely computed the largest resultant wrench in the worst direction that a grasp can generate with limited contact forces [6]. The quantity was used as a performance index for optimal grasp planning [8,11].

•  Characterized an object surface using convex facets, line segments, and discrete points, and brought forth algorithms for automatically selecting the eligible ones to provide force-closure contact positions [5].

•  Put forward an iterative procedure for dynamic force distribution [9], which runs thousand-fold faster than the previous approaches using the Simplex method. Presented a decomposition and positive combination algorithm [12], which runs in only hundreds of microseconds on a Pentium-IV PC.

•  Linearized the nonlinear friction models of soft finger contact, so that all the linearization-based methods of force-closure analysis and contact force optimization can be generalized to soft finger contact [15].

Publications

Journal Articles

[1]  Y. Zheng and C.-M. Chew, “Distance between a point and a convex cone in n-dimensional space: computation and applications,” IEEE Transactions on Robotics , under review.

[2]  Y. Zheng and C.-M. Chew, “Fast equilibrium test and force distribution for multi-contact robotic systems,” Journal of Mechanisms and Robotics, Transactions of the ASME , revision under review.

[3]  Y. Zheng and C.-M. Chew, “Efficient procedures for optimal form-closure grasp planning and fixture layout design,” Journal of Manufacturing Science and Engineering, Transactions of the ASME , under review.

[4]  Y. Zheng and C.-M. Chew, “A geometric approach to automated fixture layout design,” Computer-Aided Design , under review.

[5]  Y. Zheng and W.-H. Qian, “New advances in automatic selection of eligible surface elements for grasping and fixturing,” Robotica , accepted.

[6]  Y. Zheng and W.-H. Qian, “Improving grasp quality evaluation,” Robotics and Autonomous Systems , in press.

[7]  Y. Zheng and W.-H. Qian, “A 3-D modular fixture with enhanced localization accuracy and immobilization capability,” International Journal of Machine Tools & Manufacture , vol. 48, no. 6, pp. 677 –687, 2008.

[8]  Y. Zheng and W.-H. Qian, “On some weaknesses existing in optimal grasp planning,” Mechanism and Machine Theory , vol. 43, no. 5, pp. 576 –590, 2008.

[9]  Y. Zheng and W.-H. Qian, “A fast procedure for optimizing dynamic force distribution in multifingered grasping,” IEEE Transactions on Systems, Man, and Cybernetics ― part B: Cybernetics , vol. 36, no. 6, pp. 1417 –1422, 2006.

[10]  Y. Zheng and W.-H. Qian, “An enhanced ray-shooting approach to force-closure problems,” Journal of Manufacturing Science and Engineering, Transactions of the ASME , vol. 128, no. 4, pp. 960 –968, 2006.

[11]  Y. Zheng and W.-H. Qian, “Limiting and minimizing the contact forces in multifingered grasping,” Mechanism and Machine Theory , vol. 41, no. 10, pp. 1243 –1257, 2006 .

[12]  Y. Zheng and W.-H. Qian, “Dynamic force distribution in multifingered grasping by decomposition and positive combination,” IEEE Transactions on Robotics , vol. 21, no. 4, pp. 718 –726, 2005 .

[13]  Y. Zheng and W.-H. Qian, “Simplification of the ray-shooting based algorithm for 3-D force-closure test,” IEEE Transactions on Robotics , vol. 21, no. 3, pp. 470–473, 2005.

[14]  Y. Zheng and W.-H. Qian, “Coping with the grasping uncertainties in force-closure analysis,” International Journal of Robotics Research , vol. 24, no. 4, pp. 311–327, 2005.

[15]  Y. Zheng and W.-H. Qian, “Linearizing the soft finger contact constraint with application to dynamic force distribution in multifingered grasping,” Science in China , ser. E , vol. 48, no. 2, pp. 121 –130 , 2005.

Conference Papers

[16]  Y. Zheng and C.-M. Chew, “A numerical solution to the ray-shooting problem and its applications in robotic grasping,” IEEE International Conference on Robotics and Automation , Kobe , Japan , May 2009, accepted.

[17]  Y. Zheng and C.-M. Chew, “A new distance algorithm and its application to general force-closure test,” in Proceedings of IEEE International Conference on Robotics, Automation and Mechatronics , Chengdu , China , September 2008, pp. 313 –318.

Manuscripts in Preparation

[18]  Y. Zheng and C.-M. Chew, “A new framework for dynamic analysis of walking robots,” International Journal of Robotics Research .

[17]  Y. Zheng and C.-M. Chew, “On the intersection of a compact convex set and a ray in n-dimensional space: computation and applications,” IEEE Transactions on Robotics .

Co-authored articles

[20]  L. Yang, C.-M. Chew, Y. Zheng, and A.-N. Poo, “A study of truncated Fourier series model for bipedal walking balance control,” Robotica , revision under review.

[21]  W.-W. Huang , C.-M. Chew, Y. Zheng, and G.-S. Hong, “Bio-inspired locomotion control with coordination between neural oscillators,” International Journal of Humanoid Robotics , revision under review.

[22]  W.-W. Huang , C.-M. Chew, Y. Zheng, and G.-S. Hong, “Pattern generation for bipedal walking on slopes and stairs,” IEEE-RAS International Conference on Humanoid Robots , Daejeon , Korea , December 2008, accepted.

Academic Activities

Session Chair of IEEE International Conference on Systems, Man, and Cybernetics , 2008

Session Chair, Track Chair, and Reviewer of IEEE International Conference on CIS-RAM , 2008

Reviewer of IEEE International Conference on Robotics and Biomimetics , 2008

Reviewer of IEEE Transactions on Automation Science and Engineering , 2008, 2006

Reviewer of IEEE Transactions on Robotics , 2007

Reviewer of IEEE Transactions on Systems, Man, and Cybernetics ― part B , 2007, 2005

Hobby

Member of the NUS Staff Tennis Team, 2008-present

Runnerup of NUS Staff Tennis Match (Novice Category)

Champion of the 20th ISBG Tennis Competition of Singapore