In the future of lunar exploration,landing on some complicated terrain on lunar surface becomes more and more meaningful,so some technologies such as locating precisely and avoiding hazard automatically should be developed.At present,lunar lander location error in soft landing is very big.Although we can select a safe region in landing process,it is difficult to reduce the locating error because of the position error.In this paper,we study a precisely locating and safely landing method.It is suggested that a suspending phase is added in landing process,which can provide more time for us to make some choices.First,the landing site position can be measured precisely by star sensor or by landmark matching and triangular measurement.Then it can be compared with the desired landing position and the position error could be calculated.Second,hazard region and obstacle can be recognized.For nominal landing site,we adopt a stereovision method to create DEM map and recognize the hazard region by clustering the elevation data. Some safely landing region in vision field can be recognized by image processing and the region character can also be recognized.Also,man on the earth can recognize it by communication system in real time.Third,all the information such as recognized results and position error can be fused,then a decision to control lander floating can be automatically made.Forth,if the position error is big or landing site is not satisfactory, the lander can return to orbit and reselect a new landing site,which will increase the landing reliability.All the measures can improve the location precision and the landing survivability.In the future,this technology can satisfy the need of lunar soft landing.%在未来月球探测中,需要对一些地形复杂的区域进行探测,而在这些区域软着陆,潜在的危险性增加,这就要求着陆时具有较高的定位精度并能够自动避险.当前,由于着陆时定点的误差较大,在小范围安全地域准确着陆很难.研究了一种精确定位、安全的软着陆方式,它在软着陆过程中增加了悬停阶段.在这一阶段中,通过着陆区危险地域的识别、着陆地点位置误差的计算,加上对着陆器横向漂移的控制技术,使着陆地点的精度以及着陆生存率大为提高,能够满足未来月球探测的软着陆要求.
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