Xiaowen yu

University of California, Berkeley | UCB · Department of Mechanical Engineering

In the cell phone protective glass manufacturing industry, glass need to be first ground to a desired thickness, which requires human workers to place the glass pieces precisely into the grinder. We propose to use a 6 DOF industrial robot equipped with vision sensors to automate the process by the “pick and place” task. The precision of the placing...

Most industrial robots are indirect drive robots, which utilize low torque and high speed motors. Indirect drive robots have gear reducers between the motors and links. Due to the flexibility of transmission units, it is difficult to achieve high accuracy for trajectory tracking. In this paper, a neuroadaptive control, which is essentially a neural...

In the protective glass manufacturing industry for cell phones, placing glass pieces into the slots of the grinder requires submillimeter accuracy which only can be achieved by human workers, leading to a bottle neck in the production line. To address such issue, industrial robot equipped with vision sensors is proposed to support human workers. Th...

In the protective glass manufacturing industry for cell phones, the raw glass pieces need to be ground to the desired thickness with a grinder, which requires precise glass handling by human workers leading to a bottleneck in the production line. A low cost glass loading system with an industrial robot and web cameras is proposed to support human w...

In glass manufacturing industry, glass grinding process has significant involvement of human workers. Human workers need to load and unload glass pieces to/from the grinder. A 6 DOF industrial robot could be used to automate the process by the “pick and place” task. In this paper, a vision system is implemented to robustly detect glass piece locati...

Trajectory planning is a fundamental problem for industrial robots. It is particularly challenging for robot manipulators that transfer silicon wafers in an equipment front end module (EFEM) of a semiconductor manufacturing machine where the work space is extremely limited. Existing methods cannot give satisfactory performance since they usually so...

Joint flexibility is common in industrial robots that have geared joints. In order to design a precision motion controller that compensates the effects of joint elasticity, an accurate dynamic model of flexible joint robots is required. The models that are commonly used ignore the gyroscopic interactions between the motors and links. In order to ev...

Frog-leg robots have been widely used for handling silicon wafers inside the vacuum environment of semiconductor manufacturing machines. In order to enhance stiffness, frog-leg robots adopt a parallel structure. A main challenge of controlling wafer handling robot is avoiding vibration, which is the major cause of wafer sliding and particle contami...

This paper presents the dynamics modeling and dynamic identification of a dual-blade wafer handling robot. An explicit form dynamic model for this 8-link parallel robot is proposed. The dynamic model is transformed into a decoupled form to enable dynamic parameters identification with least-square regression. A well conditioned trajectory is chosen...

This paper presents an approach for fast modeling and iden-tification of robot dynamics. By using a data-driven machine learning approach, the process is simplified considerably from the conventional analytical method. Regressor selection using the Lasso (l 1 -norm penalized least squares regression) is used. The method is explained with a simple e...

This paper introduces the mobility analysis of a 1-DOF (Degrees of Freedom) Sarrus Linkage like 7-R single closed loop mechanism. The analysis procedure implements both group theory based criterion and reciprocal screw theory. The analysis shows that such mechanism allows rectilinear motion with full-cycle mobility. Further, unlike the Sarrus Linka...

This paper deals with a planer single-legged robot that is capable of hopping. The model of the robot is constructed as an inverted pendulum with an additional flywheel. The phases of each hopping cycle are anglicized and are treated with different control scheme. By adopting the three part control scheme that proposed by Raibert, we improve the sp...

The study on the liver deformation during the needle inserted into the target lesion, plays an important role in the robot-assisted liver tumor coagulation therapy system, which impacts the operation simulation, the pre-operative surgical planning, the treatment accuracy, and the success rate. To this end, this paper presents a quasi-static finite...

this paper presents a 6-revolutional degree of free- doms (DOFs) low-cost arm of a ping-pong robot driven by 6 actuators. Design, control, simulation and performance of this arm are examined in this paper. The task in this study is to make the ping-pong ball stay in the racket at a balanced location. The arm comprises three main components, a three...

In order to design a ping-pong robot arm system of low cost and high performance, this paper firstly designed the arm's mechanical structure according to the requirement of the robot arm, and then analysised the kinamatics and dynamatics of the system. In addition, dynamic simulation as well as control scheme are described in detail. Results of ana...