The Twin Rotor MIMO System is a higher order non-linear plant and is inherently unstable due to cross coupling between tail and main rotor. In this paper only the control of main rotor is considered which is non-linear and stable by using adaptive schemes. The control problem is to achieve perfect tracking for input reference signals while maintaining robustness and stability. Four adaptive schemes were implemented, two using Model Reference Adaptive Control under which MIT rule and Modified MIT rule are used. The other two using Adaptive Interaction, namely, Adaptive PID and Approximate Adaptive PID. It is observed that adaptive schemes fulfill all the three system performance requirements at the same time. Modified MIT rule was found to give superior performance in comparison to other controllers. Also Approximate Adaptive PID was able to stabilize the main rotor and cancel the effect of cross coupling between tail rotor and main rotor when operating simultaneously without the need for designing decouplers for the system. Thus the main rotor can be made independent from the state of the tail rotor by using Approximate Adaptive PID.

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Heat dissipation is the main problem of concern when working with high power light emitting diodes. If not controlled, the optical and electrical performance of the luminaire can get affected. A higher junction temperature induces variations in forward voltage, luminous lux, correlated color temperature, color point and peak wavelength. LED manufacturers have their operating ranges for junction temperature and driving current. Operating LEDs beyond the operating range of current may initially provide high luminous flux, but junction temperature might increase beyond the range specified, resulting in very fast degradation of luminous flux. Also, elevated junction temperatures can severely affect the lifetime and reliability of LEDs. Hence, measurement and control of junction temperature within the maximum operating range through appropriate thermal design are vital for avoiding performance degradation of the LED luminaire. This paper shows an insight on the experimentations carried out to measure the junction temperature and analyze its effect on the electrical and optical parameters of RGB LEDs within the maximum operating temperature.

All practical and real-time systems are non-linear and dynamic in nature. In the majority of studies associated with systems, it is assumed that the system is linear and the dynamics of the system is remaining constant. Though these assumptions help in easier mathematical formulations of the systems, it also imposes a lot of restrictions on understanding the system completely and its behavior in depth. In this study, the focus is on capturing the varying dynamics of Mass - Spring – Damper system using a frequency domain-based system identification approach. The system identification technique is based on an adaptive filter which is implemented through MATLAB software.

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