The current situation in which garlic cultivation is non-homogeneous and modular cannot be adapted to combine harvester operations. In this paper, a single-row harvesting and cutting integrated handheld garlic harvester is designed, and the structure and working principle of the machine are described. By analyzing the mechanics of the machine mechanism, mechanics of the machine harvesting process, and design principle of the machine chassis, the key factors affecting the garlic harvesting machine wounding rate, leakage rate, and net harvesting rate were determined. According to the force and parametric analyses of the test results, it was determined that the machine had the best harvesting effect with a conveying speed of 0.6 m/s, prop speed of 125.6 r/min, digging angle of 15°~25°, forward speed of 0.8 m/s, clamping point height of 62.15 mm, and rollover threshold value of 0.89. Compared with the traditional garlic harvester, the garlic injury rate was 57.1% lower, the garlic leakage rate was 25% lower, and the net harvest rate was 4.0% higher, which meets the requirements of the garlic harvesting operation.

Background: In the production process of apple orchard, the labor needed for apple harvest accounts about 40% of the whole production process. Objective: The auxiliary device of apple harvest was designed to improve production efficiency and reduce labor cost. Methods: This device was composed of four parts: fruit collecting mechanism, horizontal conveying mechanism, vertical conveying mechanism and rotary packing mechanism, which assists farmers in finishing the process from picking to packaging apples. Simulation and fruit damage analyses were carried out by Solid works, fruit damage included three types: Single collision, Overlapping collision and Multi-zone collision. Results: In the experiment, PID algorithm was employed to control device operate accurately. And when the motor speed were 52 r/min, 56 r/min, 60 r/min, the collection efficiency were 4900 apples/ h, 5300 apples/h, 5700 apples/h and the fruit damage rates were 4%, 5%, 8%. Conclusion: The experimental results indicated that compared with the manual operation and visual recognition-based picking robots this device’s production efficiency was improving without increasing the fruit damage rate.

A design of a pure electric vehicle controller research and development platform is presented in this article. Based on a Freescale MC9S12XDP512 microcontroller with several I/O ports, the hardware of the controller together with a controller area network communication interface to coordinate functionalities of each vehicle module is designed. The control strategy is modeled and verified by MATLAB/Simulink and AVL.Cruise softwares. The calibration of parameters is verified by a 55 kW dynamometer machine with different test scenarios. Besides, comprehensive experiments are performed and the results are obtained using the platform.

Background: Signal generator plays a crucial role in the field of automatic measurement. However, Domestic signal generator usually uses a number of discrete phases locked loop components, whose circuits are usually complex with low precision and are easily affected by the external environment. Objective: Based on direct digital synthesis (DDS) technology, a small sized high precision economic waveform generator with a simple structure and operational convenience is developed. Methodology: The hardware circuit is designed with an AT89S52 controller, and the corresponding peripheral circuit. A DDS integrated chip AD9834 is employed as a signal source, and the modular programming principle with C and assembly language is used to accomplish the software design, through which the sine wave, square wave, triangular wave signals with adjustable amplitude, frequency, and TTL signal with adjustable duty ratio can be generated. Conclusion: The whole system is advantageous with several aspects such as high frequency precision, wide frequency range, and operational convenience. The experimental results show that the stability and reliability of the waveform generator are good with a simple hardware circuit structure.

In recent years, with the development of aerospace, automotive, rolling stock, shipbuilding, military weapons and other industries, the demand for bent and rolled parts is increasing, and the requirements for roll forming accuracy are growing. With the rapid development of coal power, hydropower, nuclear power, wind power, and petrochemical industries, the design and research on roll bending machine and the profile roll forming methods have come into focus. The purpose of this study is to summarize the classification and characteristics of roll bending equipment, analyze the reasons that affect the accuracy of profile bending, and propose specific solutions. This paper summarizes the research status and patents on the existing roll bending equipment, introduces its structural characteristics, differences, and molding effects, and focuses on the difficulties, optimization, and improvement methods of roll bending molding. In this paper, the mechanical structures of the existing roll forming equipment have been analyzed and compared, the effects of different roll forming equipment on the profile bending results have been determined, and the reasons affecting the bending accuracy have been pointed out. By summarizing the patents and research on profile roll forming methods and equipment, the current situation and future research prospects of roll forming equipment are discussed. The roll forming equipment is divided into a roll bending machine, a CNC roll bending machine, and a flexible roll bending machine. Each design can meet different profile processing needs. From the design point of view, the optimization under the given processing profile can achieve relatively high processing accuracy. However, the processing of different profiles will still produce geometric defects, and there is some space for improvement in the structure of roll forming equipment, the materials of processing rollers, and the NC interactive system. Thus, further research on profile roll forming is needed in the future.