飞行员综合显示头盔位移对观察信息的影响

Influences of displacement of the pilot helmet with mounted display to information viewing

目的测定飞行员综合显示头盔位移对观察信息的影响，建立带显示器头盔的位移与信息显示的关系，为带显示器头盔设计、评价和使用提供依据。方法受试者11人，视力良好，佩戴适体的飞行员综合显示头盔。头盔上安装显示器（右眼单目），显示信息为双圆加十字，视场约3．5°。受试者取坐姿，头部放在下颌托上保持不动，显示信息调整到眼睛的正前方。头盔加载机构固定安装在头盔上对应人体耳屏点的位置，加载机构水平位于人头基础平面内。在加载机构的前端向下施加载荷，载荷大小可调。加载机构的最前端安装1只十字线型红光激光器，十字线投射在人体前面的标尺板上。加载后，激光十字线随头盔同步转动。受试者报告观察到的显示信息变化，记录激光十字线在标尺板上的位移。结果制订了飞行员综合显示头盔稳定性静加载试验方法，建立了载荷、位移和信息显示之间的关系。随着载荷增加，头盔位移增大，信息显示丢失增多。头盔位移影响对显示信息的观察。当头盔角位移达（5．0土1．7）°、垂直位移达到（3．7士1．0）mm时，内圆上端以上信息消失；当此位移达到（9．3土2．1）°和（7．4±2．5）mm时，全部信息消失。2N·m的载荷可能导致（7．3±3．1）°的角位移和（5．6±2．7）mm的垂直位移。结论本研究建立了飞行员综合显示头盔稳定性的评价指标和方法，试验结果和方法对带显示器头盔的设计、鉴定和使用具有重要意义。

Objective To survey the influences of pilot helmet displacement to informationviewing, to establish the relations between the helmet displacement and image loss, so as to provide the basis for improving helmet design, evaluating performance and guiding the use of helmet. Methods Eleven volunteers with good visual acuity wore appropriate pilot helmets with the mounted display to their right eyes. Concentric circles with cross-line was displayed in approximate 3.5° visual field. Volunteers were in seated position and their heads were kept unmovable by a jaw support. The displayed information was adjusted at right front of volunteer＇s right eye. The adjustable load was applied by an energizing mechanism on the helmet where corresponding to the tragion notches of human body and were in the basal plane of head. There was a laser device that produced red cross-line mounted at the front-end of energizing mechanism. The position of red cross-line could be projected on a ruler board installed in front of volunteer and its change with the movement of helmet could be read from the board as the load applied.-Volunteer reported the changes of his view in the meantime of loading. Results The image loss would be happened with the increase of the load. The upper inside circle was starting loss as the angular displacement of helmet reached （5.0 ± 1.7）° and the vertical displacement reached （3.7± 1.0） mm （n=9）, and when it attained （9.3±2.1）°and （7.4±2.5） mm （n=ll） all information was lost. 2 N ·m load could lead to （7.3±3. 1）°and （5.6±2.7） mm displacement （n = 11）. For testing the stability of helmet a quasi-static loading method was developed. Conclusions The pilot helmet slippage significantly impairs the pilotls information viewing and the improved design, fitted wearing in application would be necessary. The method and test parameters of assessing the stability of the helmet with mounted display are applicable. The suggestions to improve the stability of the helmet are proposed.