Sheng Cheng

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Ph.D. Student
Research Assistant
Department of Electrical and Computer Engineering,
Institute for Systems Research
University of Maryland, College Park

Email: cheng [@] terpmail [DOT] umd [DOT] edu

About me

Hello! Thank you for visiting my website. I'm a research assistant at the University of Maryland, College Park. I'm working with Dr. Derek Paley. My Curriculum Vitae can be found here.

Research

Research Interests

Robotics; optimization; control theory

Current Project

Will be posted soon.

Past Project

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Reaching a targer within a GPS-denied or costly area: a two-stage optimal control approach
Duration: July 2016–August 2018
Advisor: Dr. Nuno Martins
Project description: In this project, a new class of problem is studied where a mobile agent is controlled to reach a target. Especially, the target is enclosed within a special area. The presence of this area requires a controller to have two stages: the outer stage steers the mobile agent to enter such area while the inner stage steers the mobile agent towards the target.

We consider two types of the special area: a time-costly area and a GPS-denied area. For the time-costly area, we formulate a two-stage optimal control problem where time is explicitly specified in the cost function. We solve the problem by solving its subproblems. The key subproblem is a nonconvex quadratic programming with two quadratic constraints (QC2QP). We study the QC2QP independently and prove the necessary and sufficient conditions for strong duality in a general QC2QP. Such conditions enable efficient solution methods for a QC2QP utilizing its dual and semidefinite relaxation. For the GPS-denied area, we formulate another two-stage optimal control problem where perturbation is considered. To deal with the perturbation, we propose a robust controller using the variable horizon model predictive control. The performance of the two-stage controller for each type of the special area is demonstrated in simulations.

We construct and implement a two-stage controller that can steer a quadrotor to reach a target enclosed within a denied area. Such controller utilizes the formulation and solution methods in the theoretical study. We show experimental results where the controller can run in real-time using off-the-shelf fast optimization solvers. We also conduct a bat experiment to learn bat's strategy for target reaching inside a denied area.

This work was supported by the Air Force Center of Excellence: Nature Inspired Flight Technologies and Ideas (NIFTI).

Poster | Demo

Publications

  1. S. Cheng, “Reaching a targer within a GPS-denied or costly area: a two-stage optimal control approach,” MS thesis, 2018.

  2. S. Cheng, “Research on ping-pong balls collecting robot based on embedded vision processing system,” in Applied Mechanics and Materials, vol. 511, pp. 838–841, Trans Tech Publ, 2014.

  3. H. Wang, Y. Ma, S. Cheng, Y. Li, X. Lu, and X. Su, “Accurate robot calibration by SAI method through visual measurement,” in Robotics and Biomimetics (ROBIO), 2013 IEEE International Conference on, pp. 2679–2684, IEEE, 2013.

Honors and Awards

Courses (graduate-level)

Teaching and Mentoring

Service

Address

3148 Kim Bldg.
University of Maryland
College Park, MD 20742