a doctoral thesis at the College of Engineering at the University of Basrah discussing (Design and implementation of a low-cost control unit for a brushless DC motor with four switches and three phases based on the sliding mode technique)
The thesis presented by the student Qusay Shabib Kadhim dealt with modifying the optimal parameters (data) of the integrated proportional mode controller (PI) and sliding mode controller (SMC) for the purpose of controlling the speed of the BLDC motor with bearings using two new improved algorithms:
Lévy Flight Distribution (LFD), (D) Dragonfly
 A four-key inverter transformer with a simple control structure is proposed for the same former motor. The proposed control strategy for robust speed control is based on two feedback signals:
Speed ​​sensor ring, which is regulated by the sliding mode controller (SM&PI) and current sensor loop. The bearing BLDC motor is driven by a four-way three-phase commutator simulating a three-phase switch, LFD and DA technologies are also used to adjust the PI and SMC parameters. The Integrated Time Absolute Error (ITAE) is used as a convenient function for adjusting the parameters of the controller while the model is running (online). 
The thesis aims to design a bearing and non-bearing motor with an optimal control strategy
The thesis concluded that SMC with LFD technology has superiority over SMC with DA optimizer, traditional SMC techniques, and PI-based LFD and DA optimization-based control techniques in terms of fast tracking of the desired value, reducing velocity error to zero and lower overtaking under sudden change conditions.