Cascaded adaptive integral backstepping sliding mode and super-twisting controller for twin rotor system using bond graph model.

This work presents a bond graph (BG) model and a robust cascaded controller for a twin-rotor system (TRS). The BG model accounts for all the energetic and dynamical couplings. An adaptive integral backstepping sliding mode (AIBSM) controller is used in the outer loop to control the slow yaw and pitch dynamics of the mechanical sub-system whereas a higher-order sliding mode (HOSM) observer-based super-twisting algorithm (STA) controller is used in the inner loop to control the fast electromechanical actuator dynamics.

Modeling the dynamics of a dual input-single output closed-circuit hydraulic drive.

This work presents a scheme of a dual input-singleoutput closed-circuit hydraulic drive consisting of a pump and a hydraulic motor both variable displacement axial-piston type. It analyzes the dynamics of the hydraulic drive system through modeling and simulation. The model considers state-dependent non-linear losses and the temporal behaviors of the rotary actuators identified from the test data and these models are also considered in the simulation studies.

A comparative analysis of the pump controlled, valve controlled and prime mover controlled hydromotor drive to attain constant speed for varying load.

The article compares the dynamic performances of the pump-controlled, valve-controlled and prime-mover controlled hydromotor drive systems for a wide range of operating conditions. The control strategy adopted for each of them varies the supply flow to the hydromotor that gives the regulated drive speed. In this respect, the Simscape models are developed for the said systems that are validated experimentally.

An accurate inner diameter measurement.

The inaccurate deflection behavior of the probing system degrades the performance of the diameter-measuring machines. In this experiment, the probing is improved, applying an autocollimator and an angular positioning datum. We have devised this datum using a liquid wedge.