Space rendezvous
A space rendezvous (/ˈrɒndeɪvuː/) is a set of orbital maneuvers during which two spacecraft, one of which is often a space station, arrive at the same orbit and approach to a very close distance (e.g. within visual contact). Rendezvous requires a precise match of the orbital velocities and position vectors of the two spacecraft, allowing them to remain at a constant distance through orbital station-keeping. Rendezvous may or may not be followed by docking or berthing, procedures which bring the spacecraft into physical contact and create a link between them.
The same rendezvous technique can be used for spacecraft "landing" on natural objects with a weak gravitational field, e.g. landing on one of the Martian moons would require the same matching of orbital velocities, followed by a "descent" that shares some similarities with docking.
History
In its first human spaceflight program
In 1963 Buzz Aldrin submitted his doctoral thesis titled, Line-Of-Sight Guidance Techniques For Manned Orbital Rendezvous.[3] As a NASA astronaut, Aldrin worked to "translate complex orbital mechanics into relatively simple flight plans for my colleagues."[4]
First attempt failed
NASA's first attempt at rendezvous was made on June 3, 1965, when US astronaut
As
MSC, "just didn't understand or reason out the orbital mechanics involved. As a result, we all got a whole lot smarter and really perfected rendezvous maneuvers, which Apollo now uses."— [6]
First successful rendezvous
Rendezvous was first successfully accomplished by US astronaut Wally Schirra on December 15, 1965. Schirra maneuvered the Gemini 6 spacecraft within 1 foot (30 cm) of its sister craft Gemini 7. The spacecraft were not equipped to dock with each other, but maintained station-keeping for more than 20 minutes. Schirra later commented:[7]
Somebody said ... when you come to within three miles (5 km), you've rendezvoused. If anybody thinks they've pulled a rendezvous off at three miles (5 km), have fun! This is when we started doing our work. I don't think rendezvous is over until you are stopped – completely stopped – with no relative motion between the two vehicles, at a range of approximately 120 feet (37 m). That's rendezvous! From there on, it's stationkeeping. That's when you can go back and play the game of driving a car or driving an airplane or pushing a skateboard – it's about that simple.
Schirra used another metaphor to describe the difference between the two nations' achievements:[8]
[The Russian "rendezvous"] was a passing glance—the equivalent of a male walking down a busy main street with plenty of traffic whizzing by and he spots a cute girl walking on the other side. He's going 'Hey wait' but she's gone. That's a passing glance, not a rendezvous.
First docking
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The first docking of two spacecraft was achieved on March 16, 1966 when
The Soviets carried out the first automated, uncrewed docking between
The first Soviet cosmonaut to attempt a manual docking was Georgy Beregovoy who unsuccessfully tried to dock his Soyuz 3 craft with the uncrewed Soyuz 2 in October 1968. Automated systems brought the craft to within 200 meters (660 ft), while Beregovoy brought this closer with manual control.[11]
The first successful crewed docking[12] occurred on January 16, 1969 when Soyuz 4 and Soyuz 5 docked, collecting the two crew members of Soyuz 5, which had to perform an extravehicular activity to reach Soyuz 4.[13]
In March 1969 Apollo 9 achieved the first internal transfer of crew members between two docked spacecraft.
The first rendezvous of two spacecraft from different countries took place in 1975, when an Apollo spacecraft docked with a Soyuz spacecraft as part of the Apollo–Soyuz mission.[14]
The first multiple space docking took place when both Soyuz 26 and Soyuz 27 were docked to the Salyut 6 space station during January 1978.[citation needed]
Uses
A rendezvous takes place each time a spacecraft brings crew members or supplies to an orbiting space station. The first spacecraft to do this was
Space rendezvous has been used for a variety of other purposes, including recent service missions to the
Possible future rendezvous may be made by a yet to be developed automated Hubble Robotic Vehicle (HRV), and by the
Alternatively the two spacecraft are already together, and just undock and dock in a different way:
- Soyuz spacecraft from one docking point to another on the ISS or Salyut[citation needed]
- In the Trans Lunar Injection of the sequence third stage of the Saturn V rocket / LM inside LM adapter / CSM (in order from bottom to top at launch, also the order from back to front with respect to the current motion), with CSM crewed, LM at this stage uncrewed:[citation needed]
- the CSM separated, while the four upper panels of the LM adapter were disposed of
- the CSM turned 180 degrees (from engine backward, toward LM, to forward)
- the CSM connected to the LM while that was still connected to the third stage
- the CSM/LM combination then separated from the third stage
NASA sometimes refers to "Rendezvous,
Phases and methods
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The standard technique for rendezvous and docking is to dock an active vehicle, the "chaser", with a passive "target". This technique has been used successfully for the Gemini, Apollo, Apollo/Soyuz, Salyut, Skylab, Mir, ISS, and Tiangong programs.[citation needed]
To properly understand spacecraft rendezvous it is essential to understand the relation between spacecraft velocity and orbit. A spacecraft in a certain orbit cannot arbitrarily alter its velocity. Each orbit correlates to a certain orbital velocity. If the spacecraft fires thrusters and increases (or decreases) its velocity it will obtain a different orbit, one that correlates to the higher (or lower) velocity. For circular orbits, higher orbits have a lower orbital velocity. Lower orbits have a higher orbital velocity.
For orbital rendezvous to occur, both spacecraft must be in the same
Once the two spacecraft are sufficiently close, the chaser's orbit is synchronized with the target's orbit. That is, the chaser will be accelerated. This increase in velocity carries the chaser to a higher orbit. The increase in velocity is chosen such that the chaser approximately assumes the orbit of the target. Stepwise, the chaser closes in on the target, until proximity operations (see below) can be started. In the very final phase, the closure rate is reduced by use of the active vehicle's reaction control system. Docking typically occurs at a rate of 0.1 ft/s (0.030 m/s) to 0.2 ft/s (0.061 m/s).[22]
Rendezvous phases
Space rendezvous of an active, or "chaser", spacecraft with an (assumed) passive spacecraft may be divided into several phases, and typically starts with the two spacecraft in separate orbits, typically separated by more than 10,000 kilometers (6,200 mi):[23]
Phase | Separation distance | Typical phase duration |
---|---|---|
Drift Orbit A (out of sight, out of contact) |
>2 λmax[24] | 1 to 20 days |
Drift Orbit B (in sight, in contact) |
2 λmax to 1 kilometer (3,300 ft) | 1 to 5 days |
Proximity Operations A | 1,000–100 meters (3,280–330 ft) | 1 to 5 orbits |
Proximity Operations B | 100–10 meters (328–33 ft) | 45 – 90 minutes |
Docking | <10 meters (33 ft) | <5 minutes |
A variety of techniques may be used to effect the
Methods of approach
The two most common methods of approach for
V-bar approach
The V-bar approach is an approach of the "chaser" horizontally along the passive spacecraft's velocity vector. That is, from behind or from ahead, and in the same direction as the orbital motion of the passive target. The motion is parallel to the target's orbital velocity.[23][26] In the V-bar approach from behind, the chaser fires small thrusters to increase its velocity in the direction of the target. This, of course, also drives the chaser to a higher orbit. To keep the chaser on the V-vector, other thrusters are fired in the radial direction. If this is omitted (for example due to a thruster failure), the chaser will be carried to a higher orbit, which is associated with an orbital velocity lower than the target's. Consequently, the target moves faster than the chaser and the distance between them increases. This is called a natural braking effect, and is a natural safeguard in case of a thruster failure.[citation needed]
STS-104 was the third Space Shuttle mission to conduct a V-bar arrival at the International Space Station.[27] The V-bar, or velocity vector, extends along a line directly ahead of the station. Shuttles approach the ISS along the V-bar when docking at the PMA-2 docking port.[28]
R-bar approach
The R-bar approach consists of the chaser moving below or above the target spacecraft, along its radial vector. The motion is
When below the target the chaser fires radial thrusters to close in on the target. By this it increases its altitude. However, the orbital velocity of the chaser remains unchanged (thruster firings in the radial direction have no effect on the orbital velocity). Now in a slightly higher position, but with an orbital velocity that does not correspond to the local circular velocity, the chaser slightly falls behind the target. Small rocket pulses in the orbital velocity direction are necessary to keep the chaser along the radial vector of the target. If these rocket pulses are not executed (for example due to a thruster failure), the chaser will move away from the target. This is a natural braking effect. For the R-bar approach, this effect is stronger than for the V-bar approach, making the R-bar approach the safer one of the two.[citation needed] Generally, the R-bar approach from below is preferable, as the chaser is in a lower (faster) orbit than the target, and thus "catches up" with it. For the R-bar approach from above, the chaser is in a higher (slower) orbit than the target, and thus has to wait for the target to approach it.[citation needed]Astrotech proposed meeting ISS cargo needs with a vehicle which would approach the station, "using a traditional nadir R-bar approach."[29] The nadir R-bar approach is also used for flights to the ISS of H-II Transfer Vehicles, and of SpaceX Dragon vehicles.[30][31]
Z-bar approach
An approach of the active, or "chaser", spacecraft horizontally from the side and orthogonal to the orbital plane of the passive spacecraft—that is, from the side and out-of-plane of the orbit of the passive spacecraft—is called a Z-bar approach.[32]
See also
- Androgynous Peripheral Attach System
- Clohessy-Wiltshire equationsfor co-orbit analysis
- Common Berthing Mechanism
- Deliberate crash landings on extraterrestrial bodies
- Flyby (spaceflight)
- Lunar orbit rendezvous
- Mars orbit rendezvous
- Nodal precession of orbits around the Earth's axis
- Path-constrained rendezvous – the process of moving an orbiting object from its current position to a desired position, in such a way that no orbiting obstacles are contacted along the way
- Soyuz Kontakt
References
- ISBN 0-02-542820-9.
- ISBN 1-85233-391-X. Archivedfrom the original on April 2, 2020. Retrieved September 25, 2016.
- ^ Buzz Aldrin. "Orbital Rendezvous". Archived from the original on October 9, 2011. Retrieved May 4, 2012.
- ^ Buzz Aldrin. "From Earth to Moon to Earth" (PDF). Archived from the original (PDF) on May 27, 2014.
- ^ Oral History Transcript / James A. McDivitt Archived March 4, 2016, at the Wayback Machine / Interviewed by Doug Ward / Elk Lake, Michigan – June 29, 1999
- ^ a b "Gemini 4". Encyclopedia Astronautica. Archived from the original on November 29, 2010.
- ^ "On The Shoulders of Titans - Ch12-7". www.hq.nasa.gov. Archived from the original on April 3, 2020. Retrieved April 9, 2018.
- ^ Agle, D.C. (September 1998). "Flying the Gusmobile". Air & Space. Archived from the original on April 3, 2020. Retrieved December 15, 2018.
- ^ "NASA - NSSDCA - Spacecraft - Details". nssdc.gsfc.nasa.gov. Archived from the original on April 3, 2020. Retrieved April 9, 2018.
- ^ NSSDC ID: 1967-105A Archived April 13, 2020, at the Wayback Machine NASA, NSSDC Master Catalog
- ^ "Part 1 - Soyuz" (PDF). History Collection - Johnson Space Center - NASA. p. 11. Archived (PDF) from the original on October 7, 2022.
- ^ "Model of a Soyuz-4-5 spacecraft". MAAS Collection. Retrieved October 22, 2021.
- ^ "NSSDCA - Spacecraft - Details". NASA (in Norwegian). Retrieved October 22, 2021.
- ISBN 978-0-7619-2927-7. Archivedfrom the original on July 26, 2020. Retrieved September 20, 2020.
Most observers felt that the U.S. moon landing ended the space race with a decisive American victory. […] The formal end of the space race occurred with the 1975 joint Apollo–Soyuz mission, in which U.S. and Soviet spacecraft docked, or joined, in orbit while their crews visited one another's craft and performed joint scientific experiments.
- ^ Mark Wade. "Soyuz 11". Encyclopedia Astronautica. Archived from the original on October 30, 2007.
- ^ Marcia S. Smith (February 3, 2012). "Space Station Launch Delays Will Have Little Impact on Overall Operations". spacepolicyonline.com. Archived from the original on June 13, 2020. Retrieved June 13, 2020.
- ISBN 0-06-093269-4, page 65, "Since 1985 all Russian spacecraft had used the Kurs computers to dock automatically with the Mir station" ... "All the Russian commanders had to do was sit by and watch."
- ^ Jerry Wright (July 30, 2015). "Japanese Cargo Craft Captured, Berthed to Station". nasa.gov. Archived from the original on May 19, 2017. Retrieved May 15, 2017.
- ^ "orbitalrecovery.com". www.orbitalrecovery.com. Archived from the original on February 10, 2010. Retrieved April 9, 2018.
- ^ "A Summary of the Rendezvous, Proximity Operations, Docking, and Undocking (RPODU) Lessons Learned from the Defense Advanced Research Project Agency (DARPA) Orbital Express (OE) Demonstration System Mission" (PDF). Archived (PDF) from the original on August 7, 2020. Retrieved May 16, 2020.
- ^ a b Arrival of the ATV to the ISS, "ATV: a very special delivery - Lesson notes". ESA. Archived from the original on April 29, 2021. Retrieved April 29, 2021.
- ^ "TRACK AND CAPTURE OF THE ORBITER WITH THE SPACE STATION REMOTE MANIPULATOR SYSTEM" (PDF). NASA. Archived (PDF) from the original on August 7, 2020. Retrieved July 7, 2017.
- ^ a b c d
Wertz, James R.; Bell, Robert (2003). Tchoryk, Jr., Peter; Shoemaker, James (eds.). "Autonomous Rendezvous and Docking Technologies – Status and Prospects" (PDF). SPIE AeroSense Symposium. Space Systems Technology and Operations Conference, Orlando Florida, April 21–25, 2003. 5088: 20. S2CID 64002452. Paper 5088-3. Archived from the original(PDF) on April 25, 2012. Retrieved August 3, 2019.
- ^ λmax is the angular radius of the spacecraft's true horizon as seen from the center of the planet; for LEO, it is the maximum Earth central angle from the altitude of the spacecraft.
- ^ Lee, Daero; Pernicka, Henry (2010). "Optimal Control for Proximity Operations and Docking". International Journal of Aeronautical and Space Sciences. 11 (3): 206–220. .
- ^ a b Pearson, Don J. (November 1989). "Shuttle Rendezvous and Proximity Operations". originally presented at COLLOQUE: MECANIQUE SPATIALE (SPACE DYNAMICS) TOULOUSE, FRANCE NOVEMBER 1989. NASA. Archived from the original on July 27, 2013. Retrieved November 26, 2011.
- ^ "STS-104 Crew Interviews with Charles Hobaugh, Pilot". NASA. Archived from the original on February 3, 2002.
- ^ WILLIAM HARWOOD (March 9, 2001). "Shuttle Discovery nears rendezvous with station". SPACEFLIGHT NOW. Archived from the original on December 2, 2008. Retrieved March 17, 2009.
- ^ Johnson, Michael D.; Fitts, Richard; Howe, Brock; Hall, Baron; Kutter, Bernard; Zegler, Frank; Foster; Mark (September 18, 2007). "Astrotech Research & Conventional Technology Utilization Spacecraft (ARCTUS)" (PDF). AIAA SPACE 2007 Conference & Exposition. Long Beach, California. p. 7. Archived from the original (PDF) on February 27, 2008.
- ^ Rendezvous Strategy of the Japanese Logistics Support Vehicle to the International Space Station, [1] Archived May 5, 2021, at the Wayback Machine
- ^ Success! Space station snags SpaceX Dragon capsule [2] Archived May 25, 2012, at the Wayback Machine
- ^
Bessel, James A.; Ceney, James M.; Crean, David M.; Ingham, Edward A.; Pabst, David J. (December 1993). "Prototype Space Fabrication Platform". Air Force Institute of Technology, Wright-Patterson AFB, Ohio – School of Engineering. Accession number ADA273904: 9. Bibcode:1993MsT..........9B. Archived from the originalon May 31, 2012. Retrieved November 3, 2011.
External links
- Analysis of a New Nonlinear Solution of Relative Orbital Motion by T. Alan Lovell
- The Visitors (rendezvous) Archived April 3, 2020, at the Wayback Machine
- "Lunar Orbit Rendezvous and the Apollo Program". NASA.
- Handbook Automated Rendezvous and Docking of Spacecraft by Wigbert Fehse
- Docking system agreement key to global space policy – October 20, 2010