Jen-Yang Chen

The environmental navigation using geometric virtual reality

This article explores the construction of a geometric virtual reality platform for the environmental navigation. Non-panoramic photos and wearable electronics with Bluetooth wireless transmission functions are used to combine the user’s actions with the virtual reality environment in a first-person virtual reality platform. The 3ds Max animation software is used to create three-dimensional models of real buildings. These models are combined with the landscape models in Unity3d to create a virtual campus scene that matches real landscape. The wearable device included an ATMega168 chip as a microcontroller; it was connected to a three-axis accelerometer, a gyroscope, and a Bluetooth transmitter to detect and transmit various movements of the user. Although the development of the mechatronics, software, and engineering involved in the three-dimensional animation are the main objective, we believe that the methods and techniques can be modified for various purposes. After the system architecture was created and the operations of the platform were verified, wearable devices and virtual reality scenes are concluded to be able to be used together seamlessly.

Combining turning point detection and Dijkstra’s algorithm to search the shortest path:

In this study, image processing was combined with path-planning object-avoidance technology to determine the shortest path to the destination. The content of this article comprises two parts: in the first part, image processing was used to establish a model of obstacle distribution in the environment, and boundary sequence permutation method was used to conduct orderly arrangement of edge point coordinates of all objects, to determine linking relationship between each edge point, and to individually classify objects in the image. Then, turning point detection method was used to compare the angle size between vectors before and after each edge point and to determine vertex coordinates of polygonal obstacles. In the second part, a modified Dijkstra’s algorithm was used to turn vertices of convex-shaped obstacles into network nodes, to determine the shortest path by a cost function, and to find an obstacle avoidance path connecting the start and end points. In order to verify the feasibility of the proposed architecture, an obstacle avoidance path simulation was made by the graphical user interface of the programming language MATLAB. The results show that the proposed method in path planning not only is feasible but can also obtain good results.

The applications of fuzzy differentiable cerebellar model articulation controller in function approximation

A new neural network structure known as the fuzzy differentiable Cerebellar Model Articulation Controller (FD_CMAC) was presented in this study. The FD_CMAC mentioned in this study involved embedding the differentiable functions (such as Gaussian function) into the hypercube of the receptive field space, thereby forming non-fixed values and differentiable blocks. In addition, in the network structure, the fuzzy inference engine was introduced to replace the index addressing matrix of the association memory. Additionally, the fuzzy membership function was adopted to describe the mapping of the physical memory. The new network structure not only retained the features of CMAC, but also adopted the differentiable characteristics. The traditional weight equipartition is no longer the only method in the learning mechanism. Instead, the steepest descent method was adopted to derive at optimized parameters or weight memory contents. Confirmed through the simulation results, the network structure proposed in this study was not only feasible, but also possessed good approximation effects and convergence performance.

Grey FCMAC controller design for robotic manipulators

A design method for the Cerebella Model Articulation Controller (CMAC) with theories of the grey and the fuzzy systems is proposed in this paper. The concept of sliding mode control is also used to determine the weighting values of CMAC. It can be easily realized in the requirement of real-time control cases. However, the overall performance of control system depends on the trained CMAC; usually, it deeply depends on the structure of CMAC. Therefore, to improve the performance without learning process maybe is a good idea in designing the CMAC. In addition, a constructed compensation rule mechanism basing on the information of estimation via grey prediction is used to enhance the characteristic of CMAC. Finally, a simulation example of controlling a nonlinear system is employed to illustrate the performance and applicability of the proposed control scheme.

Study on the use of wearable devices to control objects in virtual reality

This study focuses on the design of a wearable inertial navigation device that is based on a MEMS chip and a Bluetooth wireless transmitting module and that uses the object-controlling technology of the Unity game engine to write a game script for a treasure hunt in an ancient Chinese virtual reality world. The wearable device proposed in this paper utilizes an ATmega168 chip as the main controller, which cooperates with a three-axis accelerometer and gyroscopic sensor to detect the forward, backward, and rotating movements of game players. The movement data are transmitted to the Unity 3D game engine using Bluetooth, and the game software can then control the first-person character. The interactive elements between reality and the virtual world combined as described in this paper can deliver a new experience to games, driving simulators, medical surgery, and even a variety of commercial situations. The experimental results show that the performance of the wearable device proposed by the study is stable. This paper was written with the hope that it may attract additional innovative applications that could change human lifestyles in the future.

Application of a touch panel for control of a six-axis robotic arm

The touch panel used for this experiment is the WEINTECH MT6071iE. The six-axis robotic arm was controlled by an AT90CAN128, manufactured by the ATMEL Company. A DGServo servomotor was used to drive the robots joints, which consisted of four servomotors with 12 kg torque, two 1.8 kg servomotors with reduction gear, and some precision aluminum alloy components. Driven by the servomotors, the robotic arm was able to perform motions like fetching, pinching, catching, and releasing. For example, the robotic arm was able to clamp table tennis balls and carry coke cans. In this paper, the D-H method is adopted to set the relative position coordinates of all the joints and connecting rods of the robot arm, and the terminal coordinates of the robotic arm were deduced by combining the degree of freedom with the mechanical limitation of existing arms in accordance with forward kinematics. The results of the D-H method derivation and the actual control results of the robotic arm were compared and the source of error was discussed.

Assistive computer input device for muscular atrophy patients

This article is aimed at people who suffer from muscular dystrophy or amyotrophic lateral sclerosis. A webcam captures images of the user’s head, and the computer then processes these images to calculate and transform the swinging direction and distance of the user’s head into the position of the mouse cursor and into the action of clicking the mouse. To accurately and quickly recognize these features, this article used a round sticker with a diameter of 1 cm as an identification label, which is stuck on the user’s forehead. After the webcam captures the images, the program can recognize the positions of the identification label and move the mouse cursor. Through Windows API, this article determined the user’s intention and action of clicking the mouse on the basis of a series of movements to control the mouse cursor. As confirmed by the experimental results, the proposed assisted computer entry device for muscular atrophy patients is applicable and gives good results for the e-book reading program, use of the web browser, and the execution of the application software and mini-games developed by this system structure.