Rendezvous: tí a bà gba ààyè-iṣẹ́ ìsàlẹ̀-ilà

Latí gbà ohun kan nínú oríṣíntì rẹ̀, o lè kù jú àwọn ìṣàfarawé lọ́wọ́lọ́wọ́ lọ́wọ́lọ́wọ́. Àwọn ẹ̀yàn tí a kò mọ̀ tí a bá gbọ́rọ̀gbègbè wa nínú àwọn ààyè-iṣẹ́.

11 àwọn ìṣìsẹ̀

Ni Oṣu Kẹsan 1965 Gemini 6 ati Gemini 7 lọ si inu 30 sentimita kan lati ara wọn, 300 km ni oke ilẹ. O ti gba ọdun meji ti awọn ofin ati awọn iṣe lati debẹ: awọn igbiyanju akọkọ ti fihan pe lilọ ni ọna ti o tọ si ibi-afẹde rẹ, bi ọkọ ayọkẹlẹ kan ṣe le, ko ṣiṣẹ ni orbit.

A capsule 20 degrees behind the station, 20 km lower, catches up over about 13 orbits and then transfers up. Real schedules range from about 3 hours to 2 days.

Nínú orbitì, láti gba àwọn ìṣàfarawé rẹ̀ lọ́wọ́lọ́wọ́, kò jẹ́ pé o fi ààyè pọ̀.

Wo

Gbogbo àwọn nǹkan nínú orbitì ń tẹle ìṣẹ̀dà kan: tí o bá jù lọ ní rọ́ọ̀nù. A orbit ti o kere ju ni kukuru ati spacecraft n gbe ni iyara diẹ sii lori rẹ, nitorinaa o gba ohunkohun ti o ga julọ.

Ṣẹ̀dà sí ààyè-iṣẹ́ tí o gàjú, nínú ìjáde. Àwọn kápásílẹ̀ náà tí a fi àkókò pẹ̀lú àwọn ààyè-iṣẹ́ náà láti bẹrẹ nínú àwọn ààyè-iṣẹ́ náà atí nínú rẹ̀.
Ìgbà. Ìgbà nípa ìgbà, àwọn kápílà ìsàlẹ̀-ilà náà gbàrárá. Nibẹ, 20 km ni isalẹ ti ile-iṣẹ, o gba 1.6 degrees fun orbit.
Two small burns, a mini Hohmann transfer, lift the capsule into the station’s orbit just behind it.
Ìyàn tí a fi ṣẹ́gun. Àwọn ààyè mìíràn kan nípa ìjánu-ìjánu, láriń ojú kọ̀ǹpútà tí a bá wò lọ́wọ́lọ́wọ́. Nínú ibaraẹnisọrọ́, iyara tí a fi pà jẹ́ sensọ kan ni gbogbo iṣẹju.

Àwọn ààyè-iṣẹ́

Oju-ọjọ orbital: T = 2π√(r³/μ). Pẹlu 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.

Ni gbogbo orbitu capsule, ile-iṣẹ naa ni 92.6/93.0 nikan ti abẹfẹlẹ kan: capsule gba 360° × (1 − 92.6/93.0) ≈ 1.6°, nipa 190 km. Ti o ba ti da a 20° igun gba nipa 13 orbits, ni ayika 20 wakati.

Iyipada lati 400 si 420 km jẹ nipa 5.6 m/s fun gbogbo awọn ibajẹ meji: kekere ni ibamu si iyara orbital ti 7.7 km/s.

Àwọn àyọkà ìṣàmúlò-ètò

Nínú àwọn ìṣàfarawe-ètò, àwọn ińṣẹ̀lú ìgbàdá ló àwọn èkúasiọ̀sì Clohessy-Wiltshire (Hill): ìjánu-ìjánù líǹẹ̀lì nínú fèrèsé tí wọ́n lọ nípa ààyè-iṣẹ́ náà, láti inú radial x, y nínú ààyè-iṣẹ́ náà atí n ìjánu-ìjánù alábọde áràyè-iṣẹ́:

yi − 3n²x − 2nẏ = 0, ÿ + 2nʑ = 0, z̈ + n²z = 0

Wọn sọ asọye ti o buruju: itẹsiwaju (+ẏ) ṣe ki olufẹ pọ si (x n dagba) ati lẹhinna lọ pada. Àwọn àgbèwọlé tí a ṣe ní pàtó nínú y-axis (V-bar, lati pẹ̀lú) tàbí x-axis (R-bar, lati ìsàlẹ̀-ètò, ibi tí isẹ́ aládárà náà ǹtún lè fi ìmọ̀ràn pamọ́), pẹlú àwọn ofin aabo láti jẹ́ pé mónẹ́ẹ̀lì tí kò bá lè mú ijamba kan lọ.

Wá

Fi pamọ́ pé o jẹ́ kàpásílẹ̀, àwọn ìpele 20 nínú ààyè-iṣẹ́ náà àti nínú ìwọ̀n kanna. Tí o bà fi àwọn inẹ́nì rẹ̀ lọ́wọ́lọ́wọ́ lọ́wọ́lọ́wọ́, ohun tí ǹyàn láti inú ojú-ìjárá rẹ̀, ki o si gbá ìhàn mìíràn tàbí wọ́n lè kù nínú? (Ìrọ̀: rónú nipa àkọlé Hohmann.)

Rendezvous: tí a bà gba ààyè-iṣẹ́ ìsàlẹ̀-ilà

Wo

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