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Abstract: The Special Purpose Dextreous Manipulator (Dextre) is the latest addition to the on-orbit segment of the Mobile Servicing System (MSS); Canada''s contribution to the International Space Station (ISS). Launched in March 2008, the advanced two-armed robot is designed to perform various ISS maintenance tasks on robotically compatible elements and on-orbit replaceable units using a wide variety of tools and interfaces. The addition of Dextre has increased the capabilities of the MSS, and has introduced significant complexity to ISS robotics operations. While the initial operations concept for Dextre was based on human-in-the-loop control by the on-orbit astronauts, the complexities of robotic maintenance and the associated costs of training and maintaining the operator skills required for Dextre operations demanded a reexamination of the old concepts. A new approach to ISS robotic maintenance was developed in order to utilize the capabilities of Dextre safely and efficiently, while at the same time reducing the costs of on-orbit operations. This paper will describe the development, validation, and on-orbit demonstration of the operations concept for ground-based tele-robotics control of Dextre. It will describe the evolution of the new concepts from the experience gained from the development and implementation of the ground control capability for the Space Station Remote Manipulator System; Canadarm 2. It will discuss the various technical challenges faced during the development effort, such as requirements for high positioning accuracy, force/moment sensing and accommodation, failure tolerance, complex tool operations, and the novel operational tools and techniques developed to overcome them. The paper will also describe the work performed to validate the new concepts on orbit and will discuss the results and lessons learned from the on-orbit checkout and commissioning of Dextre using the newly developed tele-robotics techniques and capabilities. [Copyright &y& Elsevier]

Abstract: Canada''s space program began in 1958 with the work that led to the launch of Canada''s first satellite, Alouette 1, in 1962. In 1967, two major reports on Canadian space research efforts called for a Canadian Space Agency (CSA). The Canadian government declined to set up an agency but chose instead in 1969 to establish an interdepartmental committee to coordinate Canada''s space efforts. The CSA finally began operations on March 1, 1989. This paper will look at government documents, reports and statements about Canadian space efforts during this time to trace the efforts to establish a CSA. This paper will also examine the creation of the Interdepartmental Committee on Space in 1969. In the 1960s and 1970s, the Canadian government focused on satellites as a communications tool and as a means of encouraging high technology industry in Canada. After joining the US space shuttle program in the 1970s, Canada was invited in the 1980s to send astronauts into space and take part in the US space station program. Although the committee structure was awkward and inconvenient, Canada''s space efforts during that time saw a high degree of political and economic success. [Copyright &y& Elsevier]

Abstract: This paper presents a spin-stabilization algorithm for the Japan Canada Joint Collaboration Satellite-Formation Flying (JC2Sat-FF) mission using magnetic actuation only. It is shown that under a reasonable assumption on the Earth’s magnetic field, the resulting control law is asymptotically stabilizing for an axisymmetric spacecraft, even under the failure of up to two magnetic torque rods and magnetic torque rod saturation. It is also stabilizing under quantization. The satellite motion remains stable under control outages, meaning that the error can be reduced by implementing the control intermittently. The effectiveness of the control law is demonstrated using a high fidelity attitude control system simulator for the JC2Sat-FF satellite. [ABSTRACT FROM AUTHOR]

Abstract: The paper addresses the evolution of the Canadian Space Station Program between 1981 and 2003. Discussions with potential international partners, aimed at jointly developing the current International Space Station program, were initiated by NASA in 1982. Canada chose, through the further development of the technologies of Canadarm on the space shuttle, to provide and operate an advanced and comprehensive external robotics system for space station, and to use the space station for scientific and commercial purposes. The program was to become a corner-stone of the new Canadian Space Agency. The development phase of the Canadian Space Station Program has been completed and two of the three major elements are currently operational in space. [Copyright &y& Elsevier]

Abstract: Defence R&D Canada (DRDC), in partnership with the Canadian Forces’ Surveillance of Space Project, is developing an array of three remotely operated, ground-based optical observatories for space surveillance (the Concept Demonstrator, CD). Manual metric accuracy testing of the CD, performed using a single sensor, began in December 2003, and focused on GPS calibration satellites. Results from this study are promising, with angular residual uncertainties less than with arcsec level biases. This short metric accuracy campaign also permitted a rough sensitivity performance check. This paper summarizes these metric accuracy and sensitivity performance checks of the CD. [Copyright &y& Elsevier]

Abstract: The second Canadian Advanced Nanospace eXperiment (CanX) satellite, CanX-2, aims to support Canadian researchers while expanding the capabilities of nanosatellites. Designed and built at the University of Toronto Institute for Aerospace Studies’ Space Flight Laboratory (UTIAS/SFL), CanX-2 will include experiments in GPS technologies, earth observation, advanced materials, and space communications protocols. In addition to the science payloads, CanX-2 will also fly engineering payloads such as a momentum-bias attitude control system, an experimental S-band communications system, a custom on-board computer, and a miniature propulsion system. With such an ambitious science platform, CanX-2 hopes to demonstrate the use of a nanosatellite as a valuable scientific tool that is cost- and schedule-effective for today''s researchers. With a target launch in late 2005 into a highly inclined orbit, the experiments and satellite subsystems described in this paper will help pave the way for future nanosatellite science missions both at UTIAS/SFL and other institutions. [Copyright &y& Elsevier]

The twelve months since IAF 2000 have been perhaps the most exciting, challenging and rewarding months for Canada since the beginning of our participation in the International Space Station program in 1984. The highlight was the successful launch, on-orbit check out, and the first operational use of Canadarm2, the Space Station Remote Manipulator System, between April and July 2001. The anomalies encountered and the solutions found to achieve this success are described in the paper.The paper describes, also, the substantial progress that has been made, during the twelve months since IAF 2000, by Canada as it continues to complete work on all flight-elements of its contribution to the International Space Station and as we transition into real-time Space Station operations support and Canadian utilization.Canada''s contribution to the International Space Station is the Mobile Servicing System (MSS), the external robotic system that is key to the successful assembly of the Space Station, the maintenance of its external systems, astronaut EVA support, and the servicing of external science payloads.The MSS ground segment that supports MSS operations, training, sustaining engineering, and logistics activities is reaching maturity. The MSS Engineering Support Center and the MSS Sustaining Engineering Facility are providing real-time support for on-orbit operations, and a Canadian Payloads Telescience Operations Center is now in place. Mission Controllers, astronauts and cosmonauts from all Space Station Partners continue to receive training at the Canadian Space Agency. The Remote Multi Purpose Room, one element of the MSS Operations Complex, will be ready to assume backroom support in 2002.Canada has completed work on identifying its Space Station utilization activities for the period 2000 through 2004. Also during the past twelve months the CSA drafted and is proceeding with the approval of a Canadian Space Station Commercialization Policy.Canadian astronauts have now participated in three ISS assembly missions - Julie Payette on STS-96, Marc Garneau on STS-97, and Chris Hadfield on STS-100 in April 2001 during which he performed Canada''s first EVA and the successful installation of the Space Station Remote Manipulator System. [Copyright &y& Elsevier]

Telesat Canada''s fifth generation Anik E satellites will be reaching the end of their operational lives in the early years of the 21st Century. Consequently, planning started about 1996 for replacement satellites. Major considerations in determining the requirements of these satellites included the minimisation of per-channel costs and increased area coverage compared to Anik E, with payloads providing service to both North and South America. The need to provide the most cost-effective C-band and Ku-band services, and the decision to cover South as well as North America, dictated the procurement of dual band satellites using the full capabilities of the new generation of high-power service modules. Anik F1, a Hughes HS702, will be the world''s largest and most powerful fixed services communications satellite when it is launched in the second half of the year 2000. Anik F1 will have a total of 84 operational channels; 36 C-band channels with an EIRP of up to 41 dB W and 48 Ku-band channels with an EIRP of up to 52 dB W. Channel bandwidths will be 36 and 27 MHz, respectively.This paper reviews the overall design and performance of Anik F1 and the main design features of the dual band communications subsystem and the high-power service module. [Copyright &y& Elsevier]