Kitdakorn Klomkarn

No-CPU Chaotic Robots: From Classroom to Commerce

For more than a decade, chaotic signals have been adopted to generate gaits for robots via simple and effective chaotic circuits within or without CPUs. The signals are used to guide a robot to navigate chaotically. This type of robots is useful in many applications ranging from engineering education such as high school science projects to military de-mining tasks alike. Computer simulations using various choices of chaotic patterns reveal that the pattern of chaotic orbit generated by Chuas circuit is the best in the sense of wide area coverage, high availability of design documentation and easy circuit construction. Experimental results show that the chaotic robots described in this article are very promising for transforming several tasks in such devices as vacuum cleaners, lawn mowers, de-mining vehicles, and so on. This cost-effective utilization can be simply done by embedding the chaotic circuits into the target applications without CPUs.

On comparison of attractors for chaotic mobile robots

In case of no map, trajectory planning could be a difficult task for robot motions to navigate around the assigned patrol areas. Chaotic mobile robots that move in chaotic patterns can be used to solve this problem. This paper is motivated by the question in seeking for suitable chaotic pattern for the aforementioned problem. Twenty-five chaotic patterns generated from various chaotic signals for the robots path are compared by computer simulation under given conditions.

Dual-line PID controller based on PSO for speed control of DC motors

This paper proposes an AI-based heuristic optimization techniques based on particle swarm optimization (PSO) to solve two applications i.e. identification of a DC motor and tuning PID controller parameters. The identification of a DC motor application, the 2nd order transfer function with time delays is obtained by the searching poles location mechanism based on PSO. This method has following steps. First, time responses of speed are determined by multi-level step input voltages. Second, the noises of time responses are reduced by wavelet soft thresholding. Finally, the noiseless time responses are identified by PSO. The tuning PID controller parameters application, the gains of proportional, integral, and derivative are determined both off-line and on-line tuning. For off-line tuning, the PID gains are optimized by PSO. On-line application, PSO-gains scheduling, adaptively adjusts the controller gains to improve the speed response under changing the speed demand and load. The simulation results show that the PSO can be efficiently used for system identification and tuning parameters of PID controller.

Combined Chaotic Attractor Mobile Robots

The application of chaos in engineering field has been attracted much attention due to many potential applications include fan heaters, air-conditions, and dish washing machines. Even though the applied chaos in robot guidance is also not new, the problem of navigation of autonomous mobile robot in a totally unknown environment can be accomplished by using chaotic function. For implementation, most of researchers use CPUs with high performance to generate the chaotic trajectory. Unlike the others, in this paper, we use a chaotic circuit, which is low cost and easy to construct for trajectory generators. The Chuas circuit and a complex butterfly attractor are combined together providing pattern diversity and area coverage. A lab-scale two-wheel mobile robot is implemented and tested in our laboratory. The experimental results confirm that the proposed scheme of combined chaotic attractors is effective for path guiding for chaotic mobile robots

A design of stream cipher based on multi-chaotic functions

This work presents the design of a stream encryption algorithm using chaotic functions. Various chaotic functions which are highly sensitive and unpredictable to initial conditions have been tested for use as a key stream. A technique employing multi-chaotic function generation for increasing the complexity of the keystream is presented. The result of a statistical test of the keystream has been proved. Thus, this encryption technique can be applied to secure communication, particularly for multimedia transmission.

Extended Baker map using Scan patterns for image encryption

In this paper, an improvement on free-size image encryption scheme using Baker map combining Scan patterns is proposed. The generalized discrete chaotic Baker map uses sequences of parameters generated by chaotic Gauss map to divide image matrix into boxes. Scrambling method is done by using Scan patterns in each boxes of chaotic Baker map. After scrambling method, chaotic 3-D Chen system is selected to do the pixel transformation. Through the experiments, the security of proposed scheme is tested by introducing keys analysis, entropy analysis, statistical analysis, and processing time so that the scheme achieves high encryption efficiency.

NEW CONSTRUCTION OF MIXED-MODE CHAOTIC CIRCUITS

This paper presents a simple scheme for designing mixed-mode chaotic circuits using quadrature core oscillators. Two mixed-mode circuits are constructed by using a few operational amplifiers in suitable combination with some autonomous/nonautonomous second/third-order chaotic circuits. Simulation and experimental results have verified the simplicity and effectiveness of the new design.

Tree robot: An innovation for STEAM education

Embracing complexity in todays world makes students impatient to learn following the conventional chalk-and-talk style of teaching, and yet plenty of helpful IT-techniques are available and surrounded. This talk provides a care-and-feeding of STEAM education, namely “Science, Technology, Engineering, Art, and Mathematics”, offering a new way of utilizing matters of natural learning to be “live”. A tree robot is created as an instrument to help students achieve the 21st century learning skills. As a result of many hours in experiments with the proposed pedagogy, the robot helps redefine what attention is and how to use it innovatively.

Communication network structure for robotic manipulators

This article presents the design and implementation of communication networks for robotic manipulator. The aim of this work is to investigate a suitable pattern for communication network structure. The designed network can be used under disaster environment through a group of information-communication robots.

Image encryption based on chaotic map and dynamic S-box

Dynamic substitution box (S-box) constructed from chaotic map is known as the secure improvement of classic S-box. But the general property `1 to 1 mapping of S-box makes the substitution not flexible. This paper proposes new method for image encryption. We use the key matrix randomization concept to apply on dynamic S-box so that S-box becomes `1 to n mapping and complexity. First, Chaotic NCA map is applied to generate dynamic S-box which is used for substitution. During substitution phase for each images value, we apply chaotic Arnold cat map combining chaotic Chen system to shuffle the positions of S-box. After that chaotic Baker map which takes parameter sequence from Gauss map is chosen to perform permutation phase. The experiments show that the secure property of this method gets high efficient from attacks.