计算机辅助设计与图形学学报
計算機輔助設計與圖形學學報
계산궤보조설계여도형학학보
Journal of Computer-Aided Design & Computer Graphics
2015年
11期
2155-2160
,共6页
杨成%唐歌实%李勰%陈光明
楊成%唐歌實%李勰%陳光明
양성%당가실%리협%진광명
航天器%大气阻力%迎风面积%阴影图
航天器%大氣阻力%迎風麵積%陰影圖
항천기%대기조력%영풍면적%음영도
spacecraft%atmospheric drug effect%cross section area%shadow map
航天器轨道低于500 km时大气阻力影响显著,该阻力与航天器迎风面的面积成正比.对于复杂外形的航天器, 其迎风面积常常进行近似处理, 会对阻力分析结果带来一定误差. 针对航天器迎风面积对大气阻力的影响, 提出一种复杂航天器迎风面积的精确计算方法. 该方法同时考虑航天器几何外形和部件运动, 根据活动部件的实际运动状态对复杂外形和结构进行精细三维建模; 利用图形学中的实时阴影生成方法产生航天器在投影面的阴影图像, 进一步分析得到航天器的迎风面积. 该方法易于实现, 能处理复杂外形航天器及其活动部件的运动, 具有较好的通用性. 将文中方法应用到我国航天测控任务中, 证明了该方法的有效性.
航天器軌道低于500 km時大氣阻力影響顯著,該阻力與航天器迎風麵的麵積成正比.對于複雜外形的航天器, 其迎風麵積常常進行近似處理, 會對阻力分析結果帶來一定誤差. 針對航天器迎風麵積對大氣阻力的影響, 提齣一種複雜航天器迎風麵積的精確計算方法. 該方法同時攷慮航天器幾何外形和部件運動, 根據活動部件的實際運動狀態對複雜外形和結構進行精細三維建模; 利用圖形學中的實時陰影生成方法產生航天器在投影麵的陰影圖像, 進一步分析得到航天器的迎風麵積. 該方法易于實現, 能處理複雜外形航天器及其活動部件的運動, 具有較好的通用性. 將文中方法應用到我國航天測控任務中, 證明瞭該方法的有效性.
항천기궤도저우500 km시대기조력영향현저,해조력여항천기영풍면적면적성정비.대우복잡외형적항천기, 기영풍면적상상진행근사처리, 회대조력분석결과대래일정오차. 침대항천기영풍면적대대기조력적영향, 제출일충복잡항천기영풍면적적정학계산방법. 해방법동시고필항천기궤하외형화부건운동, 근거활동부건적실제운동상태대복잡외형화결구진행정세삼유건모; 이용도형학중적실시음영생성방법산생항천기재투영면적음영도상, 진일보분석득도항천기적영풍면적. 해방법역우실현, 능처리복잡외형항천기급기활동부건적운동, 구유교호적통용성. 장문중방법응용도아국항천측공임무중, 증명료해방법적유효성.
The atmospheric drug must be fully taken into account for accuracy orbit determining of space-craft below 500 km. In this paper, a computer graphical approach based on the fundamental idea of shadow map is proposed to accurately calculate the cross section area of spacecraft. Firstly, the complex geometry surface of spacecraft is represented in the form of triangle grids, and the relative motion among spacecraft components is considered. Secondly, the shadow map algorithm is employed to project the spacecraft model onto a shadow plane, and then the cross section area can be found out by analysis the amount of shadow pixels in the shadow graph. The simulation and experiments are given to validate the proposed method and the results indicate that this method can deal with complex spacecrafts whose components have relative motion.