1. Funded Research Projects

1. Fault-Tolerant Workspace Analysis for Redundant Space Robots Experiencing Locked Joint Failures (NASA Kentucky EPSCoR RIDG award, PI: Biyun Xie, Funding Amount: $45,000, 8/1/2020 – 7/31/2021)
2. Human-Like Motion Planning of Collaborative Robots based on Human Arm Motion Analysis (SCEEE Development Fund, PI: Biyun Xie, Funding Amount: $32,500, 8/1/2020 – 7/31/2021)
3. Teaching Humanoid Robots by Demonstration with Preserved Dynamics and Adaptability Skills (UK College of Engineering Young Alumni Philanthropy Council Funding, PI: Biyun Xie, Funding Amount: $3,134, 1/1/2022-12/31/2022)
4. Autonomous Fault-Tolerant Operation of Redundant Robotic Arms (National Science Foundation, PI: Biyun Xie, Co-PI: Jiangbiao He, Funding Amount: $499,365, 9/1/2022-8/31/2025)
5. Developing a Demonstration-Based Motion Planner for Space Telerobots (NASA Kentucky EPSCoR RIDG award, PI: Biyun Xie, Funding Amount: $34,998, 4/1/2023 – 12/31/2024)
6. Automated Fabrication of Spherical Double-Helix Tensegrity (DHT) Robots (UK College of Engineering Mini-Grant Program, PI: Muhao Chen, Biyun Xie, Funding Amount: $10,000, 1/1/2025-5/15/2025)

2. Research Topics

1. Kinematic Design and Motion Planning of Fault-Tolerant Robots

In recent years, robots have become increasingly common for a wide range of applications, and the reliability of robots operating in structured and benign environments is quite high. However for dangerous tasks in remote or hazardous environments, where routine maintenance can not be performed, one must plan for the probability of failures. Such applications include space exploration, nuclear waste remediation, and disaster rescue. One may also want to employ fault-tolerant robots in applications requiring high degrees of safety, such as robotic surgery, rehabilitation, and human-robot interaction.

              

            (a) space exploration     (b) nuclear waste remediation      (c) disaster resecure         (d) robotics surgery    (e) human-robot interaction

                                                                                      Fig.1 The applications of fault-tolerant robots

In addition to improving the reliability of the components of the robot, one can also employ kinematically redundant robots to take advantage of their extra degrees of freedom (DOF) to tolerate different types of joint failures. It has been previously shown that an improperly designed or controlled kinematically redundant robot can actually be fault intolerant. Our research work focuses on how kinematic redundancy can be utilized to design optimally fault-tolerant robotic systems. Most of the conventional fault-tolerant control methods focus only on failure recovery, and unfortunately, it is usually too late to mitigate damages after failures occur. Our proposed kinematic design of optimally fault-tolerant robots and fault-tolerant motion planning methods in anticipation of all potential failures can guarantee task completion and optimal post-failure performance.

                                                                                       

Fig. 2 The designed optimally fault-tolerant 7R robot                        Fig. 3 Motion planning for maximizing the probability of task completion

 

2. Motion Planning for Robotic Arms

(1) Computing Optimal Collison-Free Trajectories

Computing safe paths that avoid collisions with environmental obstacles and optimal paths that minimize the path cost is a very classic problem in robot motion planning. Most of the existing methods are graph-based methods, such as Dijkstra's algorithm and A*, or sampling-based methods, such as PRM* and RRT*. Our lab focuses on developing motion planning algorithms for computing optimal collision-free trajectories based on convex optimization. 

 

(2) Human Arm Motion Imitation

Our lab focuses on developing intelligent and advanced motion planning algorithms to generate human-like motion for humanoid robots, teleoperate robots by real-time human arm motion imitation, and teach robots by human demonstration. The main applications of these studies include space exploration, manufacturing assembly, daily assistance, etc.

                     

   Fig. 4 Robot teleoperation by real-time human arm motion imitation             Fig. 5 Robot learning from human demonstration

 

3. Ethics in Human-Robot Interaction

Our lab collaborates with Dr. Jessica Barfield, an assistant professor in the School of Information Science at the University of Kentucky, to study human-robot interaction with an interest in issues of ethics that relate to the design and use of social robots. Dr. Barfiled serves as the Human-Robot Interaction Lead Faculty of our lab. Generally, robot ethics, also known as roboethics, involves ethical issues that arise from the use of robots in social contexts. While much of the research on roboethics relates to the ethical treatment of humans by robots, we will conduct research on the ethical treatment of increasingly smart robots by humans and whether the robot would be the subject of discrimination within society using different types of robots, such as Misty robot, Kinova robot, etc.