射击、射箭场所开放条件与技术标准研究

运用特尔菲法、问卷调查法、实地考察和文献资料等方法，从射击、射箭场所开放所需要场地、设施、管理制度的安全性入手，以系统论和ISO9004—2服务质量管理理论为理论基础，结合射击、射箭项目的特点和我国射击、射箭场所的实际情况，构建射击、射箭场所开放标准指标体系的基本框架，制定符合客观实际、切实可行的射击、射箭场所开放条件与技术标准。     

Aerodynamic properties of an archery arrow

Two support-interference-free measurements of aerodynamic forces exerted on an archery arrow (A/C/E; Easton Technical Products) are described. The first measurement is conducted in a wind tunnel with JAXA’s 60 cm Magnetic Suspension and Balance System, in which an arrow is suspended and balanced by magnetic force against gravity. The maximum wind velocity is 45 m/s, which is less than a typical velocity of an arrow (about 60 m/s) shot by an archer. The boundary layer of the arrow remains laminar in the measured Re number range (4.0 × 10³ < Re < 1.5 × 10⁴), and the drag coefficient is about 1.5 for Re > 1.0 × 10⁴. The second measurement is performed by a free flight experiment. Using two high-speed video cameras, we record the trajectory of an archery arrow and analyze its velocity decay rate, from which the drag coefficient is determined. In order to investigate Re number dependence of the drag coefficient in a wider range (9.0 × 10³ < Re < 2.4 × 10⁴), we have developed an arrow-shooting system using compressed air as a power source, which launches the A/C/E arrow at an arbitrary velocity up to 75 m/s. We attach two points (piles) of different type (streamlined and bullet) to the arrow-nose. The boundary layer is laminar for both points for Re less than about 1.2 × 10⁴. It becomes turbulent for Re larger than 1.2 × 10⁴ and the drag coefficient increases to about 2.6, when the bullet point is attached. In the same Re range, two values of drag coefficient are found for the streamlined point, of which the lower value is about 1.6 (laminar boundary layer) and the larger value is about 2.6 (turbulent boundary layer), confirming that the point-shape has a crucial influence on the laminar to turbulent transition of the boundary layer.     

Compound archery bow asymmetry in the vertical plane

The aim of the research was to create a mechanical and mathematical model of a compound bow and analyse its work without any prior hypothesis about the symmetry of limb deflection. The method of the research was based on the methods of theoretical mechanics, applied and computer mathematics. A pair and shift mechanism with cams and levels was used as a basis of the mechanical and mathematical model of a compound bow. The difference between results of modelling and measurement was near 7?%, while the error due to digital image deformation was evaluated to be near 1?% which was considered as acceptable. The calculated results indicated noticeable differences from simulations using the constraint of symmetrical limb deformation. Comparison of symmetrical and asymmetrical simulations with experimental data revealed that the asymmetrical simulation gave a closer match to the measured values for cam angles; the simulated and measured cam angle asymmetry was much greater than any measurement errors. Realisation of a process of solving the problem using computer mathematical system MathCAD makes it possible for specialists of physical education and sports (coaches and sport archers), who do not have a mathematical background, to use the mechanical and mathematical model that was proposed in the research for a study and training process.     

河北弓箭社考略

河北弓箭社是北宋边境地区重要的民间武术会社,曾为当时保境捍边、维护社会安定发挥过重要作用.河北弓箭社起源于"澶渊之盟",属于民间武术会社组织.它以"自卫家身"为出发点,具有自发、互助等特点."澶渊之盟"后,边境武备松弛是其产生的社会环境,有识之士的支持是其发展的动力,而贪官邀功、组织混乱,最终导致了河北弓箭社的消亡.     

On-target trajectories and the final pull in archery

Abstract

At the end of the aiming phase, an archer pulls the arrow back a little bit before he releases the shot. This pulling back of the arrow is called the “final pull”. Simultaneous with the final pull, the archer has to hold the bow calm. The aim of this paper was to examine the motion of the bow and the final pull in highly skilled archers. From a technological point of view, we wished to develop a system to measure the draw-length in the final pull that could be used during archers’ normal training. Seven archers (two males, five females), all of whom were participants at the Junior World Championships and German National Championships, performed 66 shots indoors at a target 30 m away. Each archer shot the same bow as used in competition. On-target trajectories of the aim point movement were measured. Also, the alterations of the draw-length in the final pull were determined. The results suggest that irregularities in the final pull have a negative influence on archers’ scores. Intra-individually, a smaller range of motion of the bow in the last second before the shot appears to have a positive influence on archers’ scores.     

Experimental and theoretical research in archery

The aim of this study was to introduce certain methods and research techniques and to present the results of experiments on parameters of archery equipment to optimize the interaction of the archer-bow-arrow system's elements. In order to achieve the research requirements, the following were devised: 1. A mathematical model of an arrow's movement during its interaction with a bow. 2. A mechanical model of an archer-bow-arrow system, which constitutes a device for mechanical loosing of an arrow from the bow strings (DMLA). 3. Three series of high-speed filming. The mathematical model and computer simulation were used to describe the arrow's movement for various initial conditions and various parameters of the equipment, based on which a nomogram was constructed of the optimum arrow parameters for bows of various draw forces. The device for the mechanical loosing of arrows from a bow was used to study the influence of selected parameters of the archer-bow-arrow system on the accuracy of shots. The film analysis was used to verify the mathematical and mechanical models constructed.     

Fine body movements and the cardiac cycle in archery

This study examined the relationships between postural sway, aiming time, the cardiac cycle time and the placement of the first finger movement within the electrocardiac cycle, with the quality of the arrow shot. A small group of elite male and female archers who shot either the recurve or the compound bow, freestyle or bare bow was used in this study. A total of 240 arrows were shot, classified as being of good, average or bad quality and analysed in detail. The analyses were undertaken over two occasions up to 100 days apart. The area of postural sway, as measured by the movement of the centre of pressure coordinates, varied significantly (P less than 0.05-0.001) both within and between trials for all archers and for all quality of arrows shot. There was a tendency for the area of postural sway to increase as the quality of the arrow shot decreased. This increase in postural sway exceeded, for arrows of bad quality, that exhibited as normal postural sway when standing relaxed and addressing the target with the hands at the side. Aiming time was variable within the quality of arrow shot, although it was consistent for each archer. In some cases the aiming time increased as the quality of the arrow decreased, whereas in the case of bare bow archery the aiming time tended to decrease as the quality of the arrow deteriorated. The cardiac cycle time increased significantly (P less than 0.05-0.01) as the archers approached the loose of the good quality arrows but there was no significant increase in cardiac cycle time when arrows of average or bad quality were shot. The most consistent parameter related to the quality of the shot was the placement of the first finger movement within the ST phase or the mid-cycle phase of the electrocardiogram for arrows of good quality (P less than 0.0001).     

提高我国射箭运动技术水平的思考

就当前我国和世界射箭运动技术和运动竞赛的发展趋势,提出自己的观点;根据当代射箭运动技术和运动发展趋势的分析,对影响我国射箭运动技术水平提高的瓶颈问题进行探讨,并提出解决问题的思路。