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Ottawa, Canada

The Canadian Space Agency ) was established by the Canadian Space Agency Act which received Royal Assent on May 10, 1990. The president of the agency is Walter Natynczyk who reports to the Minister of Industry. He was appointed as president on August 6, 2013.The headquarters of the CSA is located at the John H. Chapman Space Centre in Saint-Hubert, Quebec. The agency also has offices in Ottawa, Ontario, at the David Florida Laboratory , and small liaison offices in Washington, D.C.; Paris; Cape Canaveral, Florida; and Houston, Texas. Wikipedia.

Visually guided robotic capturing of a moving object often requires long-term prediction of the object motion not only for a smooth capture but because visual feedback may not be continually available, e.g., due to vision obstruction by the robotic arm, as well. This paper presents a combined prediction and motion-planning scheme for robotic capturing of a drifting and tumbling object with unknown dynamics using visual feedback. A Kalman filter estimates the states and a set of dynamics parameters of the object needed for long-term prediction of the motion from noisy measurements of a vision system. Subsequently, the estimated states, parameters, and predicted motion trajectories are used to plan the trajectory of the robots end-effector to intercept a grapple fixture on the object with zero relative velocity (to avoid impact) in an optimal way. The optimal trajectory minimizes a cost function, which is a weighted linear sum of travel time, distance, cosine of a line-of-sight angle (object alignment for robotic grasping), and a penalty function acting as a constraint on acceleration magnitude. Experiments are presented to demonstrate the robot-motion planning scheme for autonomous grasping of a tumbling satellite. Two robotics manipulators are employed: One arm drifts and tumbles the mockup of a satellite, and the other arm that is equipped with a robotic hand tries to capture a grapple fixture on the satellite using the visual guidance system. © 2012 IEEE. Source

Leveille R.J.,Canadian Space Agency | Datta S.,Kansas State University
Planetary and Space Science | Year: 2010

Lava tubes and basaltic caves are common features in volcanic terrains on Earth. Lava tubes and cave-like features have also been identified on Mars based on orbital imagery and remote-sensing data. Caves are unique environments where both secondary mineral precipitation and microbial growth are enhanced by stable physico-chemical conditions. Thus, they represent excellent locations where traces of microbial life, or biosignatures, are formed and preserved in minerals. By analogy with terrestrial caves, caves on Mars may contain a record of secondary mineralization that would inform us on past aqueous activity. They may also represent the best locations to search for biosignatures. The study of caves on Earth can be used to test hypotheses and better understand biogeochemical processes, and the signatures that these processes leave in mineral deposits. Caves may also serve as test beds for the development of exploration strategies and novel technologies for future missions to Mars. Here we review recent evidence for the presence of caves or lava tubes on Mars, as well as the geomicrobiology of lava tubes and basaltic caves on Earth. We also propose future lines of investigation, including exploration strategies and relevant technologies. © 2009 Elsevier Ltd. All rights reserved. Source

Aghili F.,Canadian Space Agency
IEEE/ASME Transactions on Mechatronics | Year: 2013

The problem of self-tuning control of cooperative manipulators forming closed kinematic chain in the presence of inaccurate kinematics model is addressed in this paper. The kinematic parameters pertaining to the relative position/orientation uncertainties of the interconnected manipulators are updated online by two cascaded estimators in order to tune a cooperative controller for achieving accurate motion tracking with minimum-norm actuation force. This technique permits accurate calibration of the relative kinematics of the involved manipulators without needing high precision end-point sensing or force measurements, and hence, it is economically justified. Investigating the stability of the entire real-time estimator/controller system reveals that the convergence and stability of the adaptive control process can be ensured if 1) the direction of angular velocity vector does not remain constant over time, and 2) the initial kinematic parameter error is upper bounded by a scaler function of some known parameters. The adaptive controller is proved to be singularity-free even though the control law involves inverting the approximation of a matrix computed at the estimated parameters. Experimental results demonstrate the sensitivity of the tracking performance of the conventional inverse dynamic control scheme to kinematic inaccuracies, while the tracking error is significantly reduced by the self-tuning cooperative controller. © 1996-2012 IEEE. Source

In the case of a major disaster, information derived from satellite observation is not only highly useful, it may at times be indispensable because of the damage caused by the disaster to ground infrastructure. The International Charter 'Space and Major Disasters' ('the Charter') has been one of the primary sources of satellite data for the past 11 years to cover events like floods, fires, tsunamis, ocean storms, earthquakes, volcanic eruptions and oil spills. With the growing membership of the Charter, an increasingly large number of sensors are now available, which can be planned with the required temporal frequency and spectral range to cover a disaster event. Some of the type Charter activation cases are reported in this article to demonstrate the innovative use of multi-satellite imagery for disaster response. © 2012 Copyright Taylor and Francis Group, LLC. Source

Leveille R.,Canadian Space Agency
Planetary and Space Science | Year: 2010

Terrestrial analogs to the Moon and Mars have been used to advance knowledge in planetary science for over a half-century. They are useful in studies of comparative geology of the terrestrial planets and rocky moons, in astronaut training and testing of exploration technologies, and in developing hypotheses and exploration strategies in astrobiology. In fact, the use of terrestrial analogs can be traced back to the origins of comparative geology and astrobiology, and to the early phases of the Apollo astronaut program. Terrestrial analog studies feature prominently throughout the history of both NASA and the USGS' Astrogeology Research Program. In light of current international plans for a return missions to the Moon, and eventually to send sample return and manned missions to Mars, as well as the recent creation of various analog research and development programs, this historical perspective is timely. © 2009 Elsevier Ltd. All rights reserved. Source

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