Easy-Implementable On-line Identification Method for a First-Order System Including a Time-Delay

This paper proposes a simple yet effective on-line identification method for a first-order system including a time-delay. This method is based on the Laplace transformation in a real number domain and is able to estimate both coefficients of the first-order system and the time-delay simultaneously. An accuracy of the identification was investigated through a simulation. As a result, precise estimation of the method was confirmed compared to an orthodox on-line estimation technique that utilized a bilinear-model. Moreover, a guideline for a tuning of their parameters used in the method is shown. Applying the method to an actual sensor identification, issues under the practical usage were investigated, and the countermeasure was mentioned

Test and Evaluation of Japanese GPR-based AP Mine Detection Systems Mounted on Robotic Vehicles

This article introduces Japanese activities regarding a project, “Research and Development of Sensing Technology, Access and Control Technology to Support Humanitarian Demining of AP Mines.” This project, which includes the research of six teams from academia and industry, has been funded by the Japan Science and Technology Agency (JST) under the auspices of the Ministry of Education, Culture, Sports, Science and Technology (MEX T). The developed systems are equipped with both groundpenetrating radar and a metal detector, and they are designed to make no explicit alarm and to leave decision-making of detection using subsurface images to the operators. To evaluate these kinds of systems, a series of trials was conducted in Japan from 8 February to 11 March 2005

Human Control Law and Brain Activity of Voluntary Motion by Utilizing a Balancing Task with an Inverted Pendulum

Human characteristics concerning voluntary motion control are investigated, because this motion is fundamental for the machine operation and human-computer system. Using a force feedback haptic device and a balancing task of a virtual inverted pendulum, participants were trained in the task, and hand motion/force was measured, and brain activity was monitored. First, through brain analysis by near-infrared spectroscopy (NIRS) and motion analysis of the pendulum, we identified a participant who was the most expert. Next, control characteristics of the most expert were investigated by considering the operational force and delay factor of a human. As a result, it was found that predictive control based on velocity information was used predominantly although a perception feedback control against the pendulum posture worked. And it was shown that an on-off intermittency control, which was a strategy for the skilled balancing, can be described well by a liner model involving two types of time shifts for the position and velocity. In addition, it was confirmed that the cortex activity for observation in an ocular motor control area and visual processing area was strong to enhance above-mentioned control strategies

Discrete-time adaptive control using a sliding mode

Adaptive control using a sliding mode in discrete time systems is proposed as a means of achieving robustness with respect to parameter variations, fast tracking to a desired trajectory, and fast parameter convergence, without increasing the chattering of the control inputs. We first prove the stability of a system in which the control inputs consist of equivalent control driven by the adaptive control law and bounded discontinuous control. The discontinuous control driven by the sliding control law is then obtained so that the output error quickly converges to zero. Finally, the performance improvements obtained by adding the sliding mode control input are shown through computer simulations

Swinging up a Pendulum by Energy Control

Properties of simple strategies for swinging up an inverted pendulum are discussed. It is shown that the behavior critically depends on the ratio of the maximum acceleration of the pivot to the acceleration of gravity. A comparison of energy-based strategies with minimum time strategy gives interesting insights into the robustness of minimum time solutions