Quantized Control Capable of Appointed-Time Performances for Quadrotor Attitude Tracking: Experimental Validation

In this paper, a quantized control capable of appointed-time performances for quadrotor attitude tracking is investigated. A continuous and piecewise behavior boundary, rather than an exponential decaying function employed in traditional pre-scribed performance control (PPC), is devised using error transformation to enforce attitude convergence to pre-assigned transient and steady zones in an appointed time. To circumvent the inertia moment uncertainties and external perturbations, an extended state observer (ESO) with only one parameter to be tuned is introduced to precisely estimate the total disturbances acting on angular rate subsystem. Addi-tionally, a hysteretic quantizer (HQ) capable of converting continuous control behaviors to finite discrete scalars is es-tablished in controller to actuator channel to reduce the transmission burden and amount of sampling data. With a novel quantization decomposition, an attitude quantized con-troller is integrated in terms of a guaranteed tracking. The prominent feature is that a prescribed appointed-time attitude response can be preserved with a decreased demand of communication bandwidth, despite of uncertainties. Theoreti-cal analysis shows that all error signals are ultimately uni-formly bounded. Eventually, the superiority of explored con-trol strategy is demonstrated through experimental results.