No abstract

An active fault-tolerant pulse-width-modulated tracker using the nonlinear autoregressive moving average with exogenous inputs model-based state-space self-tuning control is proposed for continuous-time multivariable nonlinear stochastic systems with unknown system parameters, plant noises, measurement noises, and inaccessible system states. Through observer/Kalman filter identification method, a good initial guess of the unknown parameters of the chosen model is obtained so as to reduce the identification process time and enhance the system performances. Besides, by modifying the conventional self-tuning control, a fault-tolerant control scheme is also developed. For the detection of fault occurrence, a quantitative criterion is exploited by comparing the innovation process errors estimated by the Kalman filter estimation algorithm. In addition, the weighting matrix resetting technique is presented by adjusting and resetting the covariance matrix of parameter estimates to improve the parameter estimation for faulty system recovery. The technique can effectively cope with partially abrupt and/or gradual system faults and/or input failures with fault detection.

Production information collection is an important issue for manufacturing. Therefore, the data transmission techniques for manufacturing equipment are hot spots for researchers nowadays. Traditional equipment data transmissions are based on Ethernet, which encountered issues such as high maintenance cost and unreal-time data transmission. A wireless data acquisition infrastructure for manufacturing equipment based on Wi-Fi is designed for ensuring the data transmission quality in factories.

We propose a tool for calibrating the coefficient variables of the Steinhart-Hart equation, which are used in temperature measurement with a negative-temperaturecoefficient thermistor. The previous method modifies the coefficient variables manually, but the proposed tool takes a measured temperature and automatically modifies the coefficient variables. The proposed calibration tool provides a graphical user interface program for the convenience of users. It is applied to the 4-point temperature measurement of polymerase chain reaction and has a degree of precision of ±0.1 °C in the temperature measurement evaluation.