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At present, detection of football bounce rate on football fields is mainly based on manual method in China, which is labor intensive and has low detection accuracy. To solve this problem, based on the photoelectric sensor arrays, an optical detection method is proposed for measuring football field bounce rate. A football clamping mechanism has been theoretically analyzed and then a simple and reliable football holding device was developed to perform clamping and release. A control system of the football field bounce rate detector has been constructed based on modular design principles. The detector was completed on this basis, which can achieve gripping, lifting, releasing football and bounce rate calculation. Experiments showed that the errors of detection accuracy of this equipment are not more than 1%, fully satisfying the relevant national standards.

In order to spray onto the canopy of interval planting crop, an approach of using a target spray robot with a composite vision servo system based on monocular scene vision and monocular eye-in-hand vision was proposed. Scene camera was used to roughly locate target crop, and then the image-processing methods for background segmentation, crop canopy centroid extraction, and 3D positioning were studied. Eye-in-hand camera was used to precisely determine spray position of each crop. Based on the center and area of 2D minimum-enclosing-circle (MEC) of crop canopy, a method to calculate spray position and spray time was determined. In addition, locating algorithm for the MEC center in nozzle reference frame and the hand-eye calibration matrix were studied. The processing of a mechanical arm guiding nozzle to spray was divided into three stages: reset, alignment, and hovering spray, and servo method of each stage was investigated. For preliminary verification of the theoretical studies on the approach, a simplified experimental prototype containing one spray mechanical arm was built and some performance tests were carried out under controlled environment in laboratory. The results showed that the prototype could achieve the effect of “spraying while moving and accurately spraying on target.”

The automatic sapling grafting methods and grafting robot technologies are not comprehensively studied despite the fact that they are urgently required in practice. For this reason, a sapling grafting robot is developed to implement automatic grafting for saplings. The developed grafting robot includes clipping mechanism, moving mechanism, cutting mechanism, binding mechanism, and Arduino MCU based control system, which is capable of clipping, moving, positioning, cutting, grafting, and binding saplings. Experiments show that the stock cutting efficiency is 98.4%, the scion cutting efficiency is 98.9%, the grafting efficiency is 87.3%, and the binding efficiency is 68.9%.

Bionic quadruped robots received considerable worldwide research attention. For a quadruped robot walking with steady paces on a flat terrain, using a cam drive control mechanism instead of servomotors provides theoretical and practical benefits as it reduces the system weight, cost, and control complexities; thus it may be more cost beneficial for some recreational or household applications. This study explores the robot step mechanism including the leg and cam drive control systems based on studying the bone structure and the kinematic step sequences of dog. The design requirements for the cam drive robot legs have been raised, and the mechanical principles of the leg operating mechanism as well as the control parameters have been analyzed. A cam drive control system was constructed using three cams to control each leg. Finally, a four-leg demo robot was manufactured for experiments and it showed stable walking patterns on a flat floor.

The traditional experiment teaching system of mechanical major has a lot of shortages, such as fewer class hours and fewer experiment types. Therefore, it has become a key point in the reformation of education at present. The reformational target is to construct a comprehensive experiment platform of mechanical major as the main part of experiment teaching, to promote updating the experiment content through creation of experiment, to build experiment teaching system of “three platforms, three levels, modularization and open type”. Laboratory facilities are innovated by means of students’ directing or participating in scientific research items and introduction of advanced technology. The comprehensive experiment platform has benefited to a large number of students of some majors including mechanical manufacture and automation, vehicle engineering, electric work and automation, industrial automation. Some teaching achievement awards are obtained. Scientific research atmosphere of students is animated.

The mathematic model of single valve train, lagrangian formulation, is built up. Through it, the dynamic characteristics of the single valve train are simulated with MATLAB. The result indicates that the deformation of some parts of the valve train affects their dynamic coupling. So the acceleration of valve and contact force between the cam and running pulley fluctuate severely. The valve train dynamic performances become deteriorative. The study in this paper provides a theoretical approach for the evaluation and optimization of dynamic performance of valve train.