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The Power and Transportation Future
Published in Michael Frank Hordeski, Hydrogen & Fuel Cells: Advances in Transportation and Power, 2020
Some designs use solar arrays that are several kilometers long on each side. The largest solar panels in space are being used on the International Space Station (ISS). They are 73 meters long and 11 meters wide. These panels make the ISS one of the brightest objects in the night sky.
Space exploration, science and nationalism
Published in Oliver Tristan Dunnett, Earth, Cosmos and Culture, 2021
Part of the maintenance of the International Space Station involves astronauts conducting spacewalks, or Extra-Vehicular Activities (EVAs), around the outside of the station to complete a variety of technical tasks. The principal objective of Tim Peake's spacewalk, conducted in tandem with Tim Kopra, was to replace a faulty voltage regulator at the base of one of the space station's solar power arrays. This part of the EVA had to occur during one of the station's 45-minute ‘night’ phases of orbit, when the arrays were not taking in energy from the Sun. Peake additionally was tasked with laying a 28-metre-long communications cable, before completing his spacewalk within a planned duration of over six hours.80 In the event, the spacewalk concluded in under five hours, the main objectives having been achieved, due to a bubble of liquid that was identified inside the helmet of Kopra's spacesuit, that triggered the mission's precautionary termination. The routine functionality of the EVA was interrupted in the first few minutes by an acknowledgement of Tim Peake being the first British astronaut to embark on a spacewalk, wearing the Union Flag on his spacesuit:Reid Weisman (ground control): ‘Hey Tim, it's really cool seeing that Union Jack go outside, since it's explored all over the world, and now it's explored space.’Tim Peake: ‘[laughter] … It's great to be wearing it. It's a huge privilege – a proud moment.’81
Model predictive control-based control algorithm for a target-chaser maneuvering situation
Published in Advanced Robotics, 2021
A. S. M. Gilimalage, S. Kimura
Advancements in space development have increased with collaborative research activities at the International Space Station, satellite-based network communications, deep space missions, and the enrollment of private organizations in space-related activities. However, this activity is hampered by the increase in space debris in the earth’s orbit consisting of defunct satellites, upper stages of rockets, and fragments left from collisions. Such debris can fly at high speeds; hence, even a small fraction of a part could adversely affect functioning satellites and other space modules. As of 2019, the count of large space debris exceeded 19,000 items [1]. With the probability of collisions expected to rise in the future, preventing the formation of future debris is insufficient. Active space debris mitigation is necessary to contain an increase in the total number of debris objects.
Grey-box state-space identification of nonlinear mechanical vibrations
Published in International Journal of Control, 2018
In the analysis of mechanical vibrations, one very often distinguishes nonlinearities distributed throughout (some large region of) the entire structure from localised nonlinearities, which are physically confined to a small area. Localised nonlinearities are arguably the most common in mechanical engineering practice, as they typically arise in joints interfacing substructures. Meaningful examples of this reality can be found in aerospace applications. During the modal survey of the Cassini spacecraft (Carney, Yunis, Smith, & Peng, 1997), nonlinearities resulting from the appearance of gaps in the truss supports of the Huygens probe were attested. Similarly, the analysis of in-orbit data of the International Space Station highlighted that the opening of a pin connection in the assembly of its solar arrays led to severe nonlinear manifestations (Laible, Fitzpatrick, & Grygier, 2013). Nonlinearities were also reported during ground vibration testing of the Airbus A400M, and were attributed to the elastomeric mounts supporting the four turboprop engines of the aircraft (Ahlquist, Carreño, Climent, de Diego, & de Alba, 2010).
Boundary control for a constrained two-link rigid–flexible manipulator with prescribed performance
Published in International Journal of Control, 2018
Most studies in this field have focused on the single-link manipulator. In space exploration, single-link manipulator can hardly satisfy the demands of satellite, shuttle and space station (Aghili, 2009; Liu, Li, Zhang, Gao, & Zuo, 2014). This paper will design a novel controller for the two-link rigid–flexible manipulator. The two-link rigid–flexible manipulator is widely used in applications. It has been a major concern of machinery industry in recent years. An optimal trajectory planning technique for suppressing residual vibrations in two-link rigid–flexible manipulators is proposed in Abe (2009). The social foraging behaviour of Escherichia coli bacteria to optimise hybrid fuzzy precompensated proportional derivative controller in trajectory control of two-link rigid–flexible manipulator is presented in Alavandar, Jain, and Nigam (2009).