GrabCAD 模型信息
MERLIN Scoop Design · 模型 267790
In the design of an extraterrestrial sampling system, it is critical that the following two items are specifically addressed. 1. The geophysical properties of the regolith targeted for collection 2. The environmental properties of the planet for collection In the case of lunar sample collection targeted by RASSOR, two problems need to be addressed that will otherwise render a successful terrestrial design insufficient and/or incapable of collection on the moon. 1. Testing with properly baked out KSC-1 Lunar Regolith reveal higher values of cohesion (exacerbated by the triboelectric charging from particle agitation) and internal friction (likely due to particle topology). Said plainly: particles will stick and clump together inside the collection drum. Additionally, with a cohesion over 1.0 kPA (KCS-1), particles will not necessarily flow like dry sand, instead behaving like fully saturated wet sand. “After the first Surveyor landing, it was said that “the lunar soil behaves like damp beach sand”, even though everyone knew full well there was no water on the Moon. “ [1] 2. Due to the reduced lunar gravitational field (compared to earth), the centripetal forces present in the drum cannot be ignored. At the design specification of 20 rpm, the force of gravity is only 1.6 times the centripetal force present in the drum. When accounting for the significant electrostatics that will be present with fine particles in zero atmosphere, the centripetal force can overwhelm gravitational forces. Particles will adhere to the outside wall of the collection drum, even at TDC of a drums rotation. When considering the above two points, many designs that have sample storage in the same internal cavity as sample collection will not be able to reach maximum fill ratios. Once you reach a minimum level of sample collected, that sample will clump to the outside walls of the drum preventing additional sample from being collected. In addition to the special requirements of a lunar collection system, there are general guidelines than all extraterrestrial collection devices should implement to maximize sample flow and minimize clogging. 1. Maximum particle size able to be collected must be strictly controlled in two dimensions (length & width). If a particle/sample/rock is collected that is too large, it can become permanently jammed inside the device. By controlling length and width, the only rogue sample possible can be a cigar shaped sample. If only o...
- 格式
- Rendering、STL、STEP / IGES、Other
- 分类
- Aerospace、Machine design、Robotics
- 标签
- nasadrumchallenge
- 数据更新
- 2026-10-30T00:29:10Z