Sustainable manufacturing is the future of the industry. More and more system and machine need to be employed in this field to increase the productivity and quality. In recent years, smart materials become a constant choice of many researcher to actively innovate the design and manufacture process of these kind of commercial machinery. This project from VGU on the tele-manipulator is an example for the success of smart material application.

1. General information

Project title: Design and manufacture of 4-DOF tele-manipulator with force/moment feedback system featuring smart materials
Code number: KYTH-114
Coordinator: Nguyen Quoc Hung
Implementing institution: Vietnamese German University
Duration: from 6/2018 to 12/2019
Design and manufacture a 4-DOF tele-manipulator with force/moment feedback system using smart material (MR fluid) based brakes

2. Creativeness and innovativeness in using smart materials

There have been many studies on force feedback mechanisms and some have been commercialized. In the past, most force feedback systems used electric motors and pneumatic actuators to reflect the force and torque in the working environment to the operator. The basic disadvantages of the electric motor feedback system are the bulky structure, slow response time, and low mobility. In recent years, with the strong development of research and application of smart materials, especially MR fluid, there have been a number of researches on force feedback mechanism using MR fluid. Simulation and empirical results from these studies have shown that MR fluid liked smart material has the potential to be applied in force feedback mechanisms. Although there have been a number of studies on MR fluid based force feedback systems, here are very few studies on the development of feedback systems for industrial robots that are widely used.

In 2016, PhD Nguyen Ngoc Diep and I successfully conducted the research project “Research, design and manufacture of a tele-manipulator with force feedback”. However, the ability to feedback the force from the working end-effector of the Slave to the operator of the Master is not good due to the large friction force and due to the implicit reverse problem to determine the torque at the joints of the mechanical arm. This is because the Master arm in that study is a 3-DOF Elbow manipulating mechanism.

In this study, utilizing the smart materials, we proposed a new 4-DOF tele-manipulator system featuring a spherical master manipulator, 3 rotary MR brakes and one linear MR brake. With this type of master mechanism, the basic disadvantages of the master elbow manipulator are overcome. The feedback forces can be controlled independently so it is convenient for precise control of the desired forces acting on the operator. In addition, this Master mechanism is very convenient to attach an MRF brake at the end to feedback the rolling torque.


The usage of MR fluid smart material create new direction for the project

3. Research results

After completing this research project, we have achieved the following results
– Proposing the configuration and working principle of force feedback featuring a master spherical mechanism and MR brakes (smart material MR fluid).
– Design of 4-DOF master and slave systems integrated force feedback mechanism with maximum feedback force up to 40N, feedback torque up to 5Nm.
– Develop a position and force feedback controller for the Master-Slave system
– Manufacturing the Master-Slave system with force feedback
– Develop an experimental system to evaluate the performance of the Master-Slave system
– Training 01 Master student
– Publications related to the topic.

4. Products:

a) Scientific products
– 01 ISI article
– 02 domestic / international conferences
– 02 international articles (Scopus)
– 01 domestic article

b) Applied Products
– A detailed drawings of the 4-DOF tele-manipulator system with smart materials force feedback
– A prototype of the 4-DOF tele-manipulator system with force feedback using MR brakes.

5. Transfer alternatives, application institutions, impacts and benefits of research results

a) Transfer method:

Technology transfer – commercialize products

b) Application address:

– Smart materials and system Lab, Vietnamese German University
– Further development for practical applications such as pick-place, assembly in hazardous and dangerous environments when required.

c) Benefits of research results

– Relevant scientific publications contribute to the enhancement of the scientific research position of Vietnam-Germany University. The study also contributed to the training of 01 master student. In addition, the project supports to build a research group on smart materials and systems at Vietnamese-German University. Moreover, the subject’s products can be replicated for research and teaching activities at universities in Vietnam.

– The research results create a new development in remotely controlling industrial robots working in dangerous and hazardous environments with force feedback and bring many applications in future.

– The research results contribute in improving labor efficiency in hazardous environments; contribute to minimize labor accidents affecting human health when working directly in hazardous environments.



Obstacle on the rail is the number one factor causing an accident for train transport. Therefore, a useful and practical monitor system plays an essential part in train safety. The new project from VGU tackles this matter with the use of wireless technology and simulation in research and has shown tremendous results.

1. Utilize the wireless technology application

Though not a new approach when it came to monitoring field, wireless technology has proved to be extremely convenient and call for further research to deploy its full potential.


Project title:
Design of a new monitor system for railroad and obstruction based on wireless technology to improve train safety
Code number: B2018-VGU-07
Coordinator: Dr. Do Xuan Phu
Implementing institution: Vietnamese-German University
Duration: from 1st January 2018 to 1st January 2019. The project has been expanded to 31st December 2019

2. Objectives

The main objective of the research project is to design, fabricate, and test the monitoring system for train rails based on a wireless technology system to detect safety barriers for railway traffic early. The parameters of the box follow the specific objectives as follows:

+ The size of the monitoring box is expected to be between 150 x 80 x 60 mm (length x width x height). This size depends on the sensor components, circuits, batteries,… arranged inside the box.

+ Energy-saving activities, with battery capacity operating 24/24 hours for a maximum of 1 month. The battery capacity lasts for a long time, depending on the data update adjustment to the monitoring wireless technology network.

+ Monitoring box for transferring data information is adjustable, at least 1 minute updated 1 time.

+ Connection to each other via a private wireless technology network, the connection distance between two consecutive boxes is 5 meters (this is the minimum expected range). As expected, the private network, however, if conditions allow it to be connected via the accessible internet in our country.

+ Range scan for a box within a distance of 5 meters. This is also the most extensive scan of the sensor system placed inside the box.

+ Monitoring box can use solar energy to provide monitoring. The estimated solar energy supply is 30 W. Note: this value does not include the solar cell conversion efficiency.

+ The ability of waterproofing in high rain conditions and the high humidity of our country.

+ The measurement error and information processing of the box does not exceed 5%. This difference is interpreted as the ability of the intelligent algorithm to apply in distinguishing shapes not exceeding 5% of the error.


The monitoring box using wireless technology

3. Subjects of the study

Through the above analysis, the study object is the current railway monitoring system; the selected area is intersected with the residential road. The study will focus on designing the technical monitoring box with the most economical price and the wireless technology connection and development of the signal processing algorithm from the box. The design of a monitoring connection box is based on the following combinations:

a. The circuit connects the sensor and wireless signal: the circuit is selected so that the structure is compact, uniform (easy to replace), easy to repair and maintain.

b. Signal collection sensor: The expected signal is the signal from the shape sensor (infrared), distance signal, signal to detect moving objects.

c. Wireless technology signal generator circuit and from there will connect to the central signal processing cluster for the final result.

d. The battery pack maintains the operation of the circuits and sensors with the goal of enough energy and savings so that the longest use time. The maintenance of this energy depends on updating the signal over time, for example: 1 minute/time, 5 minutes/time,…

Signal processing connection design focuses on:

a. Signal processing algorithm: clustering method, adaptive method, fuzzy model algorithm, neural networks. These algorithms will be reviewed and developed in combination with each other to increase the processing capability against signal interference. This is the core of the signal processing connection design.

b. The basic hardware system to apply this algorithm: computers and connectors collect wireless technology data from the monitoring box.

4. Approach and method of the research

The study was approached by the method

a. Calculation in research: calculate the interconnection of devices together, the ability to use energy efficiently.

b. Simulation in research: the signal processing process is simulated on a computer to test the effectiveness of the proposed processing algorithm, the ability of the network system to be connected in collecting and processing.
Both methods use analytic operations and compute numbers as needed.


Using calculation and simulation in research to estimate the effectiveness of the monitor system

5. Creativeness and innovativeness – how wireless technology was utilized

a. The newness of the project:

Designing a high-performance and low-cost obstacle monitoring box using wireless technology in the market with many expensive surveillance devices is now one of the biggest challenges for the research team.
It is also the novelty of a modern surveillance device to be suitable for all users, from the railway industry to the households. The team has succeeded in producing equipment that satisfies very high requirements and completes the project with high quality, plus scientific publications with the highest levels of gray matter.

b. The creativity of the project:

The project has used existing equipment sold in the Vietnamese market to carry out manufacturing and also uses the existing telecommunications network in our country to communicate. This is the most exceptional creativity of the project, ensuring timely replacement of damaged equipment and utilizing the current wireless technology network to connect monitoring.

Through this objective review, the economic benefits for installing railway wireless technology monitoring boxes are quite high, accounting for 98.82% for 1 year, and if considering 5 years, the benefit-cost is 80.24%. This proves that when the research is successful, in addition to improving the safety of the railway system, economic benefits are also significantly improved.
If you are interested in the project, please feel free to contact the PI – Dr. Do Xuan Phu at phu.dx@vgu.edu.vn for further details.