Past Project

1.   From 2008~2009: Research Collaboration with Professor Susumu Sugiyama’s Laboratory in Micro System Department, Ritsumeikan University, Japan.

Figure 1: The tactile soft fingertip with one sensor (left) , and the setup for sliding motion investigation.

In this collaboration, I was developing a micro force/moment sensor chip (MFMS) which was developed in Sugiyama’s Laboratory beforehand. This sensor can detect three components of force/moment based on piezo-resistive effectiveness. This was afterward embedded into a soft tip to form a complete tactile anthropomorphic robotic fingertip. By modeling the system in both static and dynamic fields, in companion with experimental results, we proved this fingertip can distinguish various types of contact with objects, recognize roughness of the objects’ surface, and especially detect the incipient slip. 

References:

Van Anh Ho, D. V. Dzung, S. Sugiyama, S. Hirai, ‘Analysis of sliding of a Soft  Fingertip Embedded with a Novel Micro Force/Moment Sensor: Simulation, Experiment, and Application.’, 2010 IEEE International Conference on Robotics and Automation, pp 889-894, Kobe Japan, May, 2009.

 Van Anh Ho, D. V. Dzung, S. Sugiyama, S. Hirai, ‘Force/ Moment Sensing During Sliding Motion Using a Micro Sensor Embedded in a Soft Fingertip.’, 2010 IEEE International Conference on Control, Automation, Robotics and Vision, pp 161-166, Hanoi, December, 2008.

2.   From 2008/08/15~2008/08/30: Internship for Master Course

Company name: Toray Engineering Ltd. Company (http://www.toray.co.jp/index.html)

Place: Otsu, Shiga, Japan. 

I was doing internship in the Research and Development Department of Toray Engineering Ltd. Company. I was asked to implement experiments on investigating quality of welded cells of a newly-developed solar cell welding machine. The operation of the machine was totally automated, however, the process to bring best quality of welding had not found out yet. I had to test many samples with various materials of soldering, temperature, period of heating or cooling, etc. Afterward, each welded sample was suffered a tensile test until the welded spot was broken. The state of broken weld spot was observed in a scanning electron microscope (SEM) to see which process of welding produced best quality solder. After two weeks, I could manage to control the operation of the machine, and we found out the best process of welding for solar cells. I also studied about working environment in a big Japanese production company as Toray. Since the detailed results are secret, I am not allowed to public here.

The result of the internship was evaluated as A+.

3.   From 2007/02~20007/06: Research Collaboration for Undergraduate Thesis

Company’s name: BKSys Ltd Company

Place: Hanoi, Vietnam

Colleagues: Hoang-Anh NGUYEN, Thanh-Trung PHAN

Advisor: Prof. Hong-Quang NGUYEN, Hanoi Univ. of Technology.

We were developing the Two-wheel Self Balancing Scooter which can transport human under his control. This scooter is capable to balance on its two wheels, spin on the spot, move on some typical terraces, and turn left or right. Firstly, we attempted to model this scooter as a mobile-wheeled inverted pendulum (MWIP) model, using state-space method. A Kalman filter was used as an observer to estimate output states of system under noise, feed back to PID controller to control the tilting angle, and moving velocity of the scooter. The model was implemented in MATLAB-Simulink, showing that this system is controllable. Secondly, the theoretical model was implemented on the real scooter. 

Figure 1: The Self-Balancing Scooter model with Kalman filter in Simulink.

Figure 2: Balance simulation. Purple plot shows           Figure 3: Moving simulation. Yellow line shows the response of vehicle's tilting angle, yellow one       position of the vehicle at constant velocity illustrates the position.                                 which is shown by cyan plot.

This scooter has two wheels attached by two BLDC motors, and their controllers; a central processor using dsPIC30F4011. There were an accelerometer and a gyro scope sensor employed to measure the angular and angular rate of the scooter. Signals from these sensors were inputs of a digitalized Kalman filter to estimate quickly exact value of actual tilting angle of the scooter. It was afterward feed-backed into a PID controller to assure that the angle of the scooter always keeps the zero value under external disturbances. Software in the central processor takes above tasks, as well as controls the scooter under commands of human from command board, such as stop, spin, move, turn left/right. This scooter succeeded to carry an normal adult overcoming some common terraces such as flat road, slope with an average velocity of 7km/h. In this collaboration, I contributed mostly the work with investigating the system theoretically; simulation, BLDC control, and Kalman filter implementation.

Figure 4: The Self-Balancing Scooter which can transport human easily.

My lovely team mates: Anh-Quang DUONG, Hoang-Anh NGUYEN, Thinh NGUYEN, Thanh-Trung PHAN,(Me), Dinh-Hai VU 

This research was recognized as best undergraduate thesis in the department, awarded first place in Research Award for Students in Hanoi University of Technology, finalist for National Technology Award for Students.

4.   From 2006/12~2007/01: Internship for Undergraduate Course

Company’s name:  BKSys Ltd Company

Place: Hanoi, Vietnam.

Colleagues: Hoang-Anh NGUYEN, Thanh-Trung PHAN

We were in charge to design a controller, including hardware and software for a High Power Brushless Direct Voltage Motor (BLDC). Hardware including an inverter using MOSFETs (metal–oxide–semiconductor field-effect transistor), MOSFET’s driver circuits, Hall-effect current sensor, and a dsPIC30F4011 were designed by my mate Hoang Anh. Software was written in C environment for dsPIC304011. This system is a PID current-feedback close loop to control angular velocity and output moment for BLDC. Controlled range of angular velocity can vary from 10~800 rpm (rounds per minute), with current of 8A. As a result, this system is capable for applications which require high torque at low velocity, such as wheelchair, mobile robots, etc.

The result of the internship was evaluated as A+.

Figure 1. The Brushless DC motor (left) and its hardware implementation.