International Berthing and Docking Mechanism
| IBDM fact sheet | ||
|---|---|---|
 IBDM Engineering Model | ||
| Description | ||
| Role: | Part of SNCs Dream Chaser to supply cargo to the International Space Station | |
| Prime: | QinetiQ Space under ESA contract | |
| Dimensions | ||
| Outer width: | 1.42 m | 4.66 ft |
| Passageway: | 0.8 m | 2.62 ft |
| Mass: | < 325 kg | < 716.5 lb |
| Performance | ||
| Endurance: | At least 210 days | |
| Capture success rate: | > 98% using IDSS initial conditions | |
| Avionics | ||
| Redundancy: | Hot redundant + passive safe mode | |
| Interfaces: | 28 V DC | |
| UART or MIL1553 | ||
The International Berthing and Docking Mechanism (IBDM) is the European androgynous low impact docking mechanism that is capable of docking and berthing large and small spacecraft. The development of the IBDM is under ESA contract with QinetiQ Space as prime contractor.[1][2]
History
The IBDM development was initiated as a joint development programme with NASA JSC. The first application of the IBDM was intended to be the ISS Crew Return Vehicle (CRV). In the original Agency to Agency agreement, it was decided to develop an Engineering Development Unit (EDU) to demonstrate the feasibility of the system and the associated technologies. NASA JSC were responsible for the system and avionics designs and ESA for the mechanical design. However since the cancellation of the CRV program, the two Agencies have independently progressed with the docking system development.
The IBDM is now designed to be compatible with the International Docking System Standard[3] (IDSS) and is hence compatible with the future ISS International Docking Adapters (IDA) on the US side of the ISS.
The European Space Agency has now started a cooperation with SNC to provide the IBDM for attaching this new vehicle to the ISS in the future.[4] NASA expects to select commercial contractors to resupply the International Space Station in September 2015.[5]
Design
The IBDM provides both docking and berthing capability. The docking mechanism comprises a Soft Capture Mechanism (SCS), and a structural mating system called the Hard Capture System (HCS), explained in more detail below. The IBDM avionics runs in hot redundancy.
Soft Capture Mechanism
The SCS utilizes active control using 6 servo-actuated legs from RUAG Space (Switzerland) which are coordinated to control the SCS ring in its 6 degree of freedom. The leg forces are measured to modify the compliance of the SCS ring to facilitate alignment of the active platform during capture.[6] A large range of vehicle mass properties can be handled. Mechanical latches achieve soft capture.
Hard Capture Mechanism
The HCS uses structural hook mechanisms to close the sealed mated interface. QinetiQ Space has developed several generations of latches and hooks to come to the final hook design.[7]
Advantages
The key feature of IBDM is that it is fully computer controlled resulting in the following main advantages:
- Performance: a very high capture success rate, enabled by force-controlled capture mode
- Smooth: it provides a capability for low impact docking in order to reduce or eliminate the need for impact energy to achieve spacecraft interface alignment and capture. A low impact mechanism greatly reduces the contact forces during mating and as a result alleviates the large loads that the structure is required to withstand.
- Flexible: a large range of vehicle mass properties can be handled, as the SCS uses active control.
- Autonomous: the IBDM comprises autonomous switch-over from primary to redundant lane in case of a failure.
- Safe: the IBDM comprises a backup or safe mode in which the Steward platform behaves like an electro-magnetic damper. This mode is used if two failures have occurred in the IBDM avionics - or even - if no electrical power is applied to the IBDM and hence provides a safe situation for both the vehicle and the ISS, even during the docking phase.
Application
The American company Sierra Nevada Corporation (SNC) is developing the Dream Chaser, which is a small reusable spacecraft that is a candidate to transport astronauts and/or crew to the ISS. The European Space Agency has started a cooperation with SNC to potentially provide the IBDM for attaching this new vehicle to the ISS in the future.[4] The IBDM will be mounted to the unpressurised cargo module, which will be ejected before reentry.
Status
The IBDM development is currently at Critical Design Review level. An engineering model of the mechanism and its avionics has been developed. The performance of the system has been verified at the certified SDTS docking test facility at NASA JSC.[8]
References
- ↑ Caporicci, Marco (2010). "IBDM: THE INTERNATIONAL BERTHING DOCKING MECHANISM FOR HUMAN MISSIONS TO LOW EARTH ORBIT AND EXPLORATION". IAC. Retrieved 4 January 2016.
- ↑ "QinetiQ Space wins contract with European Space Agency to develop International Berthing Docking Mechanism". QinetiQ . 3 June 2014. Retrieved 4 January 2016.
- ↑ International Docking System Standard (Rev. C ed.). November 20, 2013.
- 1 2 "QinetiQ Space Wins ESA Contract for International Berthing Docking Mechanism".
- ↑ "Decision on new space station cargo contracts deferred". Spaceflight Now. Retrieved April 22, 2015.
- ↑ Claessens, Dirk (2012). "DEVELOPMENT OF THE INTERNATIONAL BERTHING AND DOCKING MECHANISM COMPATIBLE WITH THE INTERNATIONAL DOCKING SYSTEM STANDARD". IAC. Retrieved 4 January 2016.
- ↑ K. De Vriendt; H. Dittmer; D. Vrancken; P. Urmston; O. Gracia; M. Caporicci. "Evolution of the IBDM Structural Latch Development into a Generic Simplified DesignEvolution of the IBDM Structural Latch Development into a Generic Simplified Design". Retrieved 4 January 2016.
- ↑ Dittmer, Helder; Paijmans, Bart (16 Oct 2016). "The International Berthing Docking Mechanism (IBDM):Demonstrating full compliance to the International Docking System Standard (IDSS)". 66th International Astronautical Congress.
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