The phenomenon of stick-slip vibration is widespread in the exploration of deep and ultra-
deep wells. It causes the reduction of the mechanical drilling rate and wastes the driving …

Emergence of shale oil & gas and the unconventional wellbore condition motivate an
increasing number of studies on analysis and control of the downhole drilling system. Due to …

This paper proposed an equivalent input disturbance (EID)-based approach to control the
vertical down-hole drilling process. To describe a drill string which is typically long with large …

A control method is proposed to suppress stick-slip vibration of drillstring system based on
tracking control with zero steady-state error and state observer in this paper. A multiple …

We discuss boundary control of a wave equation with a non-linear anti-damping boundary
condition. We design structured finite-dimensional-output feedback controllers that stabilize …

This paper uses the wave equation to explain the torsional motion of the drill-string system.
Solving the wave equation with the D'Alembert method, a neutral time-delay model of the …

This thesis investigates a novel state-constrained control technique, namely 'Barrier
Avoidance Control', that can be applied to a high-order system to address state barriers of …

This paper concerns robust stabilization for a class of nonlinear systems with uncertainties
and disturbaces. The equivalent-input-disturbance (EID) approach is utilized to estimate the …

This dissertation investigates dynamics modeling, optimization, and control methodologies
of the down-hole drilling system, which can enable a more accurate and reliable automated …