In this article, a geometrical model of different microtextures is established for an axial piston pump valve plate. A finite differential method was used to solve the Reynolds equation for the oil film thickness and pressure, which were simulated under different microtextures. The influence of microtexture shape and structure on performance was studied and optimal parameters sought. Different convergence gaps are formed by different microtexture radii, and they produce different hydrodynamic effects. The lubrication characteristics of the valve plate are better when a microtexture is used and are influenced by the type of microtexture. We reached the following conclusions: (1) The lubrication characteristics of the valve plate are influenced by different microtexture parameters and can be improved by optimizing the microtexture parameters; (2) There is an optimal parameter combination when adding microtexture with three shapes (spherical, cylindrical and square) and the optimal dimensionless oil film pressure lubrication characteristics can be obtained; (3) The degree of improvement in the dimensionless oil film pressure lubrication characteristics was (listed from highest to lowest): micro-hemispherical texture > micro-cylindrical texture > micro-square texture.

Efficient intersection planning is one of the most challenging tasks for an autonomous vehicle at present. The degree of response to other traffic participants and whether the path tracking effect is good are the key aspects that determine the performance of planning algorithm for an autonomous vehicle. In order to deal with these problems, in this paper, the frame structure of POMDP (Partially Observable Markov Decision Processes) and the time distance coordinate system are combined to carry out the speed planning for the self-propelled vehicle. The speed planning designs a novel POMDP model to ensure effective prediction of behavioral intentions and decision-making at intersections with no traffic signs. Specifically, the method is considered both the driving position and the time range of arrival of the vehicle at the intersection in real-world situations. At the same time, the algorithm is projected the state information into the time distance coordinate system in the form of probability, and used the value iteration method to solve the optimal solution, so as to improve the adaptability of the algorithm to real-world scenarios. Furthermore, MPC control is added on this basis. Rational use of dynamic MPC and kinematic MPC can effectively reduce the tracking error, improve the stability of tracking, and carry out finer control when the speed frequently fluctuates.

The motion of water droplets induced by Lamb waves on an inclined glass substrate, which is excited by a single phase transducer (SPT), has been investigated in this study. There are three main factors that affect the motion, namely, input power, droplet volume, and plate inclination angle. When the droplet volume and plate inclination angle are fixed, the velocities of the two (advancing and receding) edges of the droplet are found to be strongly related to the input power. Moreover, under a certain input power and a certain droplet volume, the larger the angle, the higher the velocities of the advancing and receding edges of the droplet. However, the droplet velocity is not proportional to the droplet volume under a certain input power and a certain angle. In addition, two-dimensional time-dependent incompressible Navier–Stokes equations of the droplet on the inclined glass slope are investigated.

In this work, the motion of droplets on an inclined non-piezoelectric curved substrate is investigated to study the performance of the Lamb waves (LWs)-driven surface cleaning of the camera lens or other optical components. The droplets do not slide forward on the curved substrate with an inclination less than 5° is verified by experiments. And then, the shape changes of droplets are discussed from experiments and simulation. A two-phase flow simulation model is established using the level set method, which the deformation of gas-liquid interface can be clearly observed when the droplet moves. The observation results that the movement of droplets on the inclined curved glass driven by LW are propelled periodically in a stretching and spreading phases. To investigate the effect of LWs on droplets removal, the movement distance of droplets are measured in four main factors, namely, substrate inclination, input power, droplet volume and surface curvature.