Dextre: Improving Maintenance Operations on the International Space Station

Paper number

IAC-07-D1.3.09

Author

Mr. Elliott Coleshill, MacDonald Detwiller Robotics, Canada

Coauthor

Mr. Daniel A. Rey, Canadian Space Agency, Canada

Coauthor

Dr. Richard Rembala, MDA, Canada

Coauthor

Mr. Layi Oshinowo, MDA, Canada

Year

2007

Abstract

The Special Purpose Dexterous Manipulator (SPDM), also known as “Dextre” is currently slated to launch in December 2007 for deployment on the International Space Station (ISS) as the final component of Canada’s Mobile Servicing System (MSS). Dextre’s primary role on the Space Station will be to perform remove and replacement (R\&R) maintenance tasks on robotically compatible hardware such as On-orbit Replaceable Units (ORUs), thereby eventually easing the burden on the ISS crew.
With an “aging” ISS, the need to R\&R without Extravehicular Activities (EVAs) is required – ISS assembly will not be complete until 2011 with some elements having been on-orbit for up to 8 years. Presently, the burden on the crew to maintain the Station precludes almost all intended science investigation and so finding ways to assist the crew in performing their tasks or offloading the crew completely when appropriate is key to realizing the ultimate benefits of the ISS program. Shifting many of the maintenance tasks to Dextre will be an immediate benefit to reducing crew EVA demand either by allowing for EVR-only or combination EVR-EVA activities with one or the other as the primary system. Additionally, some of the crew Intravehicular Activity (IVA) workload for controlling Dextre can be reduced by using the Ground Control (GC) philosophy now in place for the Canadarm2. This facilitates non-critical robotic tasks such as powering up and free-space maneuvering to be commanded from the ground. 
Based on an increasing clarity regarding the challenges of external maintenance on the ISS, Dextre is being considered for use in a number of ways with the ultimate objective of improving ISS operations while reducing and optimizing the use of crew time. Through the use of ground control of various tasks, pre-positioning hardware in order to save time during an EVA task, acting as a temporary storage platform to break an EVA day into manageable timelines, and extending the physical reach and range of the Canadarm2, there are plans to extend Dextre beyond it original role. 
This paper discusses the planned activities and operations for Dextre and rationale for how these will help optimize the use of crew resources on the ISS.

Abstract document

IAC-07-D1.3.09.pdf

Manuscript document

IAC-07-D1.3.09.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.