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In order to study the tire friction characteristics under wet skid surface, the “pseudo” hydrodynamic pressure bearing effect is used to be equivalent to the hydrodynamics of water film, and an advanced Lugre tire hydroplaning dynamic model is developed by combining the arbitrary pressure distribution function. The water hydroplaning dynamic tests were carried out for 285/70R19.5 tire under wet of different water film thickness and dry conditions, and the parameters of the advanced Lugre tire dynamic model were identified. The results show that the tire water-skiing model proposed in this paper can effectively simulate the friction characteristics of tires under different water film thicknesses. Under dry conditions, 0.5mm water film and 1mm water film road conditions, the relative errors of the maximum tire friction coefficient between the tested and advanced Lugre tire model are 1.11%, 0.12% and 0.16%, respectively.

When the aircraft towing operations are carried out in narrow areas such as the hangars or parking aprons, it has a high safety risk for aircraft that the wingtips may collide with the surrounding aircraft or the airport facility. A real-time trajectory prediction method for the towbarless aircraft taxiing system (TLATS) is proposed to evaluate the collision risk based on image recognition. The Yolov7 module is utilized to detect objects and extract the corresponding features. By obtaining information about the configuration of the airplane wing and obstacles in a narrow region, a Long Short-Term Memory (LSTM) encoder-decoder model is utilized to predict future motion trends. In addition, a video dataset containing the motions of various airplane wings in real traction scenarios is constructed for training and testing.

The tire frictional characteristics, which are the most critical factors of braking performance, depend on the road condition. Unsafe accidents always occur when driving in a hostile environment, especially under snowy road conditions. The coupled dynamic behaviors between the tire and the snow on the road are closely related to the water film generated from the tire rolling on the snow. The winter tire and summer tire with specification 175/65R14 are modeled separately by the finite element method (FEM), and the stiffness characteristics of the winter tire are analyzed. Further, the coupled dynamic model between the tire and the snowy road is built by considering the tire motion effects of the water film. The tires’ friction coefficient is investigated under the straight snowy road with different velocities.

Nowadays the ultrasonic radar, infrared detection, laser scanning radar or other perception technologies have been widely used in the automatic docking conditions. However, it’s not absolutely applicable in severe weather such as heavy rain and snow days, especially in the operation not allowed to fail, for example, the docking of the future unmanned towbarless towing vehicle (TLTV) with the expensive civil plane. A novel mechanism is proposed for relatively position and posture measuring between the TLTV and the aircraft nose tire during the automatic docking operation. The geometrical relationship between the towing vehicle and the nose tire is obtained by mathematical calculation. The position and posture of the nose tire have been obtained by splice angles and the length of rotatable rods connected with the vehicle during the docking operation.

The towbarless aircraft taxiing system (TLATS) consists of the towbarless towing vehicle (TLTV) and the aircraft. The tractor realizes the towing work by fixing the nose wheel. During the towing process, the tractor driver may cause the aircraft to collide with an obstacle because of the blind spot of vision leading to the accident. The special characteristics of aircraft do not allow us to modify the structure of the aircraft to achieve collision avoidance. In this paper, three degrees of freedom (DOE) kinematic model of the tractor system is established for each of the two cases of pushing and pulling the aircraft, and the relationship between the coordinates of each danger point and the relatively articulated angle of the TLATS and the velocity of the midpoint of the rear axle is derived.

The vehicle suspension plays a significant role in alleviating the vibrations translated from the rough road and most of the vibrations are dissipated by the hydraulic shock absorber. Vibration energy harvesting technology is widely concerned for the self-powered wireless sensor system in intelligent vehicle. However, the system dynamic characteristics are influenced by the Ampere force which induced by the electro-magnetic induction of the vibration energy recovery system. Considering the mechanical electromagnetic coupling, a dynamic model of a quarter vehicle with vibration energy recovery system is established. The additional dynamic stiffness and normalized damping characteristics of the electromagnetic system are investigated by applying the harmonic displacement excitations with different frequencies.

The towbarless aircraft taxiing system (TLATS) consists of the towbarless towing vehicle (TLTV) and the aircraft, of which the nose wheel is lifted and fixed by the picking up and holding system of the TLTV. The aircraft is towed to the destination in a long distance with a high speed of about 40 km/h only driven by the TLTV, which has the advantages of efficiency and economy by comparing with the traditional towing operation at a low speed of 5 km/h and with a short towing distance of about 50 m. However, the increase of the towing velocity leads to an deteriorate vibration problem in terms of the uncomfortable of the driver and reduction of the structure safe life limit, due to the lack of the chassis suspension for the vibration isolation of the TLTV. Therefore, the air suspension is introduced to the TLTV to alleviate the vibration. The dynamic model of the TLATS with air suspensions is derived.

The vehicle ride comfort behavior is closely associated with the vibration isolation system such as the primary suspension system, the engine mounting system, the cab suspension system and the seat suspension system. Air spring is widely used in the cab suspension system for its low vibration transmissibility, variable spring rate and inexpensive automatic leveling. The mathematical model of the air spring is presented. The amplitude and frequency dependency of the air spring's stiffness characteristic is highlighted. The air spring dynamic model is validated by comparing the results of the experiment and the simulation. The co-simulation method of ADAMS and AMESim is applied to integrate the air spring mathematical model into the cab multi-body dynamic model. The simulation and ride comfort test results under random excitation are compared.

Hydraulic Engine Mount (HEM) is widely used in vehicle Powertrain Mounting System (PMS) for vibration isolation. The dynamic performances of an HEM are strongly frequency dependent. A Five-Parameters Fractional Derivative model is used to describe the dynamic properties of an HEM. A 1/4 car model is applied to evaluate the effect of frequency-dependent dynamic stiffness which using measured data of a typical hydraulic engine mount. The excitations from engine and road are considered in the simulation. The generalized- α method is presented to solve the vehicle model with five-parameter fractional derivative model.

The ride comfort of the commercial vehicle is mainly affected by several vibration isolation systems such as the primary suspension system, engine mounting system and the cab mounting system. A rigid-flexible coupling model for the truck was built and analyzed in multi-body environment (ADAMS). The method applying the excitation on the wheels center and the engine mountings in time domain was presented. The variables' effects on the ride performance were studied by design of experiment (DOE). The optimal design was obtained by the co-simulation of the ADAMS/View, iSIGHT and Matlab. It was found that the vertical root mean square (RMS) acceleration and frequency-weighted RMS acceleration on the seat track were reduced about 17% and 11% respectively at different speeds relative to baseline according to ISO 2631-1.