Rendezvous: kulowa pa malo oyenda

Pa December 1965, Gemini 6 ndi Gemini 7 anayenda m’masentimita 30 kuchokera pamodzi, 300 km pamwamba pa dziko lapansi. Anatenga zaka ziwiri za maphunziro ndi kuphunzira kuti afike kumeneko: zofuna zayamba zinasonyeza kuti kuyenda mozungulira pamalo anu, monga woyendetsa ndege angachite, sikungagwiritsidwe ntchito m’mapiri.

Pa orbit, kuti afike pa inu kugwa pansi, si kufulumizitsa.

Onani

Zosefera zonse m’ma orbits zimatsatira lamulo limodzi: lower is faster. M’malo mwake, orbit ya pansi ndi yocheperako ndipo ndege yonyamula anthu imayenda mofulumira kwambiri, chifukwa chake imapeza chilichonse chomwe chili pamwamba.

1. Kuyamba ku orbit ya pansi, pambuyo pa chida. Kapangidwe ka capsule ndi nthawi yoyambira njira ina m’mbuyo mwa malowa komanso pang’onopang’ono pansi pake.
2. Phasing. Lap pambuyo pa lap, capsule yotsika imapeza pang’ono. Here, 20 km below the station, it gains 1.6 degrees per orbit.
3. Matenda awiri ochepa, mini Hohmann transfer, kunyamula capsule mu orbit ya malowa m’mbuyo mwake.
4. Kufika kwachidule. Mamita angapo apitawo amayenda mofulumira, mozungulira m’njira yoyendetsa ndege, ndi makompyuta omwe amayang’aniridwa ndi ogwira ntchito. Pa kulumikizana kuthamanga kwa kumapeto ndi masentimita angapo pa mphindi.

Kumvetsa

Mtundu wa 2: (T) ndi (R). Ndi μ = 398.600 km³/s²:

• Capsule at 400 km (r = 6,778 km): 92.6 minutes.
• Station at 420 km (r = 6,798 km): 93.0 minutes.

Each capsule orbit, the station covers only 92.6/93.0 of a lap: the capsule gains 360° × (1 − 92.6/93.0) ≈ 1.6°, about 190 km. Kutseka 20 ° kugwa kumatenga pafupifupi orbits 13, pafupifupi maola 20.

Kusinthanitsa kuchokera ku 400 mpaka 420 km kumawononga pafupifupi 5.6 m/s kwa mmodzi mwa ma burns awiri: tiny poyerekeza ndi 7.7 km / s ya orbital kufulumira.

Woyang’anira

Pamenepo, opanga ma rendezvous amagwiritsa ntchito Clohessy-Wiltshire (Hill) equations: kuzungulira kwa linearized m’ma frame omwe amayenda ndi chida, ndi x radial, y along-track ndi n chida chapakati choyenda:

yim − 3n²x − 2nẏ = 0,   ÿ + 2nʒ = 0,   z̈ + n²z = 0

Zimafotokoza zachikhalidwe chosadziwika: kukanikiza patsogolo (+ẏ) kumachititsa kuti wofuna kunyamula awonjezere (x akukula) ndipo kenako amayenda mozungulira. Njira yopitako imapangidwa m’mbali mwa y axis (V-bar, kuchokera kumbuyo) kapena x axis (R-bar, kuchokera pansi, komwe kuyendetsa kwachilengedwe kumathandiza kuletsa), ndi malamulo achitetezo kuti injini yolephera siyibweretse kugwa.