Mobile Servicing System
The Mobile Servicing System (MSS), is a robotic system on board the International Space Station (ISS). Launched to the ISS in 2001, it plays a key role in station assembly and maintenance; it moves equipment and supplies around the station, supports astronauts working in space, and services instruments and other payloads attached to the ISS and is used for external maintenance. Astronauts receive specialized training to enable them to perform these functions with the various systems of the MSS.
The MSS is composed of three components:
- the Space Station Remote Manipulator System (SSRMS), known as Canadarm2.
- the Mobile Remote Servicer Base System (MBS).
- the Special Purpose Dexterous Manipulator (SPDM, also known as "Dextre" or "Canada hand").
The system can move along rails on the Integrated Truss Structure on top of the US provided Mobile Transporter cart which hosts the MRS Base System. The system's control software was written in the Ada 95 programming language.[1]
The MSS was designed and manufactured by
Canadarm2
Officially known as the Space Station Remote Manipulator System (SSRMS). Launched on
In addition to moving itself around the station, the arm can move any object with a
On-board operators see what they are doing by looking at the three Robotic Work Station (RWS) LCD screens. The MSS has two RWS units: one in the Destiny module and the other in the Cupola. Only one RWS controls the MSS at a time. The RWS has two sets of control joysticks: one Rotational Hand Controller (RHC) and one Translational Hand Controller (THC). In addition to this is the Display and Control Panel (DCP) and the Portable Computer System (PCS) laptop.
In recent years, the majority of robotic operations are commanded remotely by flight controllers on the ground at
Some time before 12 May 2021 Canadarm2 was hit by a small piece of orbital debris damaging its thermal blankets and one of the booms.[2] Its operation appeared to be unaffected.[2]
Canadarm 2 will also help to berth the
Latching End Effectors
Canadarm2 has two LEEs, one at each end. A LEE has 3 snare wires to catch the grapple fixture shaft.[5] Another LEE is on the Mobile Base System's Payload ORU Accommodations (POA) unit. The POA LEE is used to temporarily hold large ISS components. One more is on the Special Purpose Dexterous Manipulator (SPDM, also known as "Dextre" or "Canada hand"). Six LEEs have been manufactured and used in various locations on the ISS[citation needed].
S/N | Initial location | Current location |
---|---|---|
201 | LEE B | POA LEE |
202 | LEE A | Earth, to be refurbished for Ground Spare |
203 | POA LEE | LEE A |
204 | Spare stored on ELC1 | LEE B |
205 | Earth, Ground Spare | Spare stored on exterior ISS |
301 | SPDM LEE | SPDM LEE |
Special Purpose Dexterous Manipulator
The Special Purpose Dexterous Manipulator, or "Dextre", is a smaller two-armed robot that can attach to Canadarm2, the ISS, or the Mobile Base System. The arms and their power tools are capable of handling delicate assembly tasks and changing Orbital Replacement Units (ORUs) currently handled by astronauts during spacewalks. Although Canadarm2 can move around the station in an "inchworm motion", it is unable to carry anything with it unless Dextre is attached. Testing was done in the space simulation chambers of the Canadian Space Agency's David Florida Laboratory in Ottawa, Ontario. The manipulator was launched to the station on 11 March 2008 on STS-123.
Mobile Base System
The Mobile Remote Servicer Base System (MBS) is a base platform for the robotic arms. It was added to the station during
The MBS is equipped with four
The MBS also supports astronauts during extravehicular activities. It has locations to store tools and equipment, foot-restraints, handrails and safety tether attachment points as well as a camera assembly. If needed, it is even possible for an astronaut to "ride" the MBS while it moves at a top speed of about 1.5 meters per minute.[6] On either side of the MBS are the Crew and Equipment Translation Aids. These carts ride on the same rails as the MBS. Astronauts ride them manually during EVAs to transport equipment and to facilitate their movements around the station.
Enhanced ISS Boom Assembly
Installed on May 27, 2011, is a 15.24 meter (50-foot) boom with handrails and inspection cameras, attached to the end of Canadarm2.
-
Shuttle Remote Manipulator System (RMS) holding OBSS boom on STS-114
-
Astronaut Scott Parazynski (at right) riding the OBSS boom to repair the solar array during STS-120
Other ISS robotics
The station received a second robotic arm during
Originally connected to Pirs, the ISS also has two Strela cargo cranes. One of the cranes could be extended to reach the end of Zarya. The other could extend to the opposite side and reach the end of Zvezda. The first crane was assembled in space during STS-96 and STS-101. The second crane was launched alongside Pirs itself. The cranes were later moved to the docking compartment Poisk and Zarya module.
List of Cranes
Name | Agency or Company | Launch |
---|---|---|
Canadarm 2
|
Canadian Space Agency | April 19, 2001 |
Dextre | Canadian Space Agency | March 11, 2008 |
See also
- MacDonald Dettwiler and Associates (MDA), the manufacturers of Canadarm2
- Space Shuttle Orbiters
- European Robotic Arm, a third robotic arm installed on the ISS
- The Remote Manipulator System, used on the ISS module Kibo
- Dextre, also known as the Special Purpose Dexterous Manipulator (SPDM), used on the ISS
- Strela, a crane used on the ISS to perform similar tasks as the Mobile Servicing System
References
- ^ "Case Study: MDA - Canadian Space Arm" (PDF). AdaCore. Retrieved 2009-10-15.
- ^ a b Michelle, Star (31 May 2021). "Space Debris Has Hit And Damaged The International Space Station". Science Alert. Retrieved 31 May 2021.
- ^ "Axiom Station Assembly Sequence — Axiom Space Axiom Space". Axiom Space. Retrieved 2021-08-09.
- ^ "A Private Space Station Might Be Born From the ISS - Seeker". www.seeker.com. 25 January 2017. Retrieved 2021-09-26.
- ^ EVA Checklist STS-126 Flight Supplement, 2008 pages 115, 117, 118
- ^ a b "The Slowest and Fastest Train in the Universe". NASA.
- ^ a b "About the Mobile Base System". Government of Canada. 20 June 2018. Retrieved January 2, 2023.
- ^ Garcia, Mark (22 October 2018). "Mobile Servicing System". NASA.
- ^ "A Space-Age Robot". MIT Technology Review. Retrieved January 2, 2023.
- ^ "CSA - STS-111 - Mobile Base System - MBS Design". Canadian Space Agency. Archived from the original on 2008-09-21. Retrieved 2008-03-15.
Further reading
- Robotic Transfer and Interfaces for External ISS Payloads. 2014 good diagrams of SSRMS/Canadarm2