Torque Vectoring Control of RWID Electric Vehicle for Reducing Driving-Wheel Slippage Energy Dissipation in Cornering

The anxiety of driving range and inconvenience of battery recharging has placed high requirements on the energy efficiency of electric vehicles. To reduce driving-wheel slip energy consumption while cornering, a torque vectoring control strategy for a rear-wheel independent-drive (RWID) electric vehicle is proposed. First, the longitudinal linear stiffness of each driving wheel is estimated by using the approach of recursive least squares. Then, an initial differential torque is calculated for reducing their overall tire slippage energy dissipation. However, before the differential torque is applied to the two side of driving wheels, an acceleration slip regulation (ASR) is introduced into the overall control strategy to avoid entering into the tire adhesion saturation region resulting in excessive slip. Finally, the simulations of typical manoeuvring conditions are performed to verify the veracity of the estimated tire longitudinal linear stiffness and effectiveness of the torque vectoring control strategy. As a result, the proposed torque vectoring control leads to the largest reduction of around 17% slip power consumption for the situations carried out above.

Numerical analysis of meshing heating of involute spur gear

Involute spur gears generate heat due to tooth surface meshing friction. Excessive temperature rising affects transmission accuracy and reduces work reliability.. By establishing the normalized coordinates of the meshing curve and based on the frictional heat generation theory, the mathematical analysis model of the meshing surface heating is studied, the factors affecting the average heat flux density of meshing are explored, and the distribution law of these factors along the normalized coordinate of the meshing is analysed. The analysis shows that the tangential velocity of the meshing point and the half-bandwidth of the time domain contact have the greatest influence on the average heat flow density; the average heat flow density distribution of the driving wheel and the driven wheel are similar. The heat flow density of the driving wheel is greater than that of the driven wheel. Tooth shape modification minimizes tooth surface meshing contact stress, reduces meshing heat generation, controls temperature rise and improves transmission reliability.

Dynamic Simulation Analysis and Experiment of Large-caliber Self-propelled Pipeline Crawler Based on ADAMS

The force states of driving wheels are different when the self-propelled pipeline crawler moves in the pipeline, so it is difficult to carry out accurate theoretical analysis and calculation on the force and output torque values of each driving wheel in horizontal, climbing and turning conditions of the crawler. Due to the complex mechanical properties of pipeline sealing and the limitation of visualization, it takes a long period and high cost to develop the robot in pipeline by experimental means. With the gradual application of virtual simulation means, the complicated dynamic analysis and solution process in the past has become relatively easy. In this paper, Solid works is used to establish a simplified model of the crawler, and ADAMS is used to analyze and simulate the dynamics of the crawler. The force of the multi-wheel driven pipeline crawler is given under the condition of horizontal, climbing 35° and turning, which provides the necessary analysis method and theoretical basis for the design optimization and improvement. Finally, the horizontal, climbing and bending motion performance of the crawler is verified by comprehensive pipeline experiment.

Algorithm for improving energy efficient wheel motor for electric vehicles

In accordance with the tendency to reduce the number of mechanical assemblies in electric driven machines and mechanisms, attempts are made to bring the electric motor and the actuator of the mechanism into a single whole. Thereby increasing the quality and productivity of the machines. A motor-wheel is a kind of a driving wheel, an actuator of a traction electric drive system of a pneumatic-wheeled transport vehicle. The work is devoted to the modernization of urban electric transport by equipping it with high-energy efficiency motor wheels, based on the frequency converter system - asynchronous motor. This paper describes the improvement algorithm and technological features.

Research on the mathematical model and measurement method of instantaneous output power of vehicle driving wheels

Aiming to solve the problem that the internal resistance of the dynamometer is regarded as a constant force by the traditional test method, which causes the measurement precision of the vehicle driving wheel instantaneous output power to be insufficient, a measurement system for the drum movement was constructed, a measurement method for the vehicle driving wheel instantaneous output power was put forward, and a mathematical model of the vehicle driving wheel instantaneous output power was established. Model analysis and experimental results showed that the actual output power of the driving wheel was reflected more accurately by the proposed method, and the accuracy of the measurement results was not affected by the vehicle speed. The output torque of the vehicle driving wheel calculated by the proposed model was closer to the road running resistance of the vehicle, which provided technical support for the accurate no-dismounting and rapid detection of the vehicle driving wheel output power and the accurate simulation of the vehicle road running resistance by the dynamometer.

Digitalization of MSMEs as the Key to Economic Recovery during the Pandemic

Efforts were made by the state to restore its economy. MSMEs as an important asset and the driving wheel of the Indonesian economy, which also contributes significantly to the country's GDP, are almost entirely affected by this condition. Some small businesses are unable to survive, mostly due to lack of innovation, and involvement in digitization. There needs to be empowerment for each MSMEs as a step to strengthen the economy and increase competitiveness in domestic and international markets.

Improving the Energy Efficiency of Movement and Cross-Country Capacity of an Articulated Mobile Wheeled Robot by Controlling an Individual Electric Traction Drive

Articulated wheel-walking robots having a good combination of weight and load capacity, as well as high cross-country capacity and maneuverability are among the promising schemes of mobile robotic systems. One of the main requirements for such complexes is a high level of autonomy. In this regard, the task of improving the energy efficiency of the articulated mobile wheeled robot movement (especially in long-term transport mode) by reducing the driving wheel skid becomes urgent. An algorithm for the operation of the antiskid system of such a robot with an individual traction electric drive has been developed. It provides an increase in the energy efficiency of robot movement and cross-country capacity by reducing the skid of the driving wheels. The efficiency of the antiskid system operation algorithm has been proved by the simulation methods.

Frequency Spectra Analysis of Drawbar Pulls Generated by Special Driving Wheels Improving Tractive Performance

Driving wheel operation is characterized by force interactions with the ground, manifested in the form of vibrations. Signals generated by driving wheels can be analyzed in the frequency spectrum of tractor drawbar pull. The paper presents the analysis of a drawbar pull signal generated by a tractor equipped with two types of special driving wheels and standard tires. Beside the evaluation of special driving wheels’ properties according to drawbar power, the frequency spectra of measured signals were analyzed using a fast Fourier transformation. The model spectrum intervals for the standard tires, spike tires, and blade wheels were calculated according to the number of rubber lugs, blades, or spikes and compared with the experimental results. The results showed that the specific frequencies typical for blades and spikes were identified in model spectrum intervals. In the case of standard tires, the spectrum components typical for rubber lugs of the tire tread pattern were not identified. The highest amplitude of the typical frequency component was detected in the case of blades wheels, which showed the highest difference in drawbar power in comparison with the standard tires. Smaller dimensions of spikes resulted in lower amplitude and lower difference in drawbar power in comparison with the standard tires.