Robotic excavator trajectory control using an improved GA based PID controller

Kalman filter for mobile-robot attitude estimation: Novel optimized and adaptive solutions

Trajectory control of electro-hydraulic position servo system using improved PSO-PID controller

Applying pre-deformation to high strength aluminum alloy has significant impacts on shape formation and mechanical properties of component in creep age forming process. The suitable degree of pre-deformation can not only improve forming efficiency, but also attain sound mechanical properties. This paper experimentally investigates the effects of pre-deformation on creep strain, mechanical properties and microstructures of AA2219. The results show that pre-deformation can prolong the duration of primary creep stage and considerably facilitate creep strain. Through mechanical property tests, it is found that pre-stretched AA2219 possesses a high-performance “peak ageing strengthening region” with little fluctuation during creep ageing of 7–13 h. Further examinations by TEM tests indicate that this is due to the fact that the morphology of precipitates in this region remains unchanged without remarkable coarsening. Based on microstructural evolution and ageing strengthening theory, a set of physically-based creep ageing constitutive model is proposed. The developed model takes into account the effect mechanism of pre-deformation and incorporates the coupled interactions of microstructure, yield strength and creep strain. A good agreement between predicted and experimental values is achieved, which verifies the accuracy of the developed model. Hence, it provides the theoretical basis for the prediction of shape and properties in creep age forming of large-scale panel component.

Effect of pre-deformation on creep age forming of 2219 aluminum alloy: Experimental and constitutive modelling

To improve the controllability of an electro-hydraulic position servo control system while simultaneously enhancing the anti-jamming ability of a PID controller, a compound PID controller that combines the beetle antennae search algorithm with PID strategy was proposed, and used to drive the position servo control system of the electro-hydraulic servo system. A BAS-PID controller was designed, and the beetle antennae search algorithm was used to tune PID parameters so that the disturbance signal of the system was effectively restrained. Initially, the basic mathematical model of the electro-hydraulic position servo control system was established through theoretical analysis. The transfer function model was obtained by identifying system parameters. Then, the PID parameter-tuning problem was converted into a class of three-dimensional parameter optimization problem, and gains of PID controllers were adjusted using the beetle antennae search algorithm. Finally, by comparing the effectiveness of different algorithms, simulation and experimental results revealed that the BAS-PID controller can greatly enhance the performance of the electro-hydraulic position servo control system and inhibit external disturbances when different interference signals are used to test the system’s robustness.

https://www.mdpi.com/1424-8220/19/12/2727/pdf

Yi Ye

Papers

Position control of nonlinear hydraulic system using an improved PSO based PID controller