If you’ve ever had trouble with a footpath, bus stop, or other piece of urban infrastructure, you probably know the hassles of dealing with a local council. It can be incredibly difficult just to track down the right avenue to report issues, let alone get them sorted in a timely fashion.
Yesterday, the Indian Space Research Organization’s (ISRO) Chandrayaan-3 spacecraft performed a powered soft-landing on the Moon, officially making India the fourth country to achieve a controlled descent to the lunar surface. Up to this point, only the United States, China, and the Soviet Union could boast successful landings on our nearest celestial neighbor.
Chandrayaan-3 Packed for Launch
What’s more, Chandrayaan-3 has positioned itself closer to the Moon’s south pole than any other mission in history. This area is of great interest to scientists, as there is evidence that deep craters in the polar region contain considerable deposits of frozen water. At the same time, the polar highlands receive almost constant sunlight, making it the perfect location to install solar arrays. These factors make the Moon’s south pole an ideal candidate for a future human outpost, and Chandrayaan-3 is just one of several robotic craft that will explore this area in the coming years.
But as is usually the case with space exploration, the success of Chandrayaan-3 didn’t come easy, or quickly. The ISRO started the Chandrayaan program in 2003, and launched the Chandrayaan-1 mission in 2008. The craft successfully entered lunar orbit and surveyed the surface using a wide array of instruments, many of which were provided by foreign space agencies such as NASA and the ESA. In 2019 the far more ambitious Chandrayaan-2 mission was launched, which included a lander and small rover. While the orbiter component of Chandrayaan-2 was a complete success, the lander crashed into the Moon’s surface and was destroyed.
With Chandrayaan-3 now safely on the surface of the Moon, there’s much work to be done in the coming days. The planned mission lifetime for both the lander and rover is a single lunar day, which equals just about two weeks here on Earth. After that, the vehicles will be plunged into a long stretch of frigid darkness which they likely won’t survive.
To keep track of a location in a two-dimensional space, two measurements are needed. Most of the time, we would naturally think to do this by the Cartesian method, measuring position along one axis and then again along a second axis. But this isn’t the only way of keeping track of position. Polar coordinates, where the distance from the origin and an angle are used as the two measurements, works just as well, and sometimes can be a preferred method. This pen plotter tosses the expected Cartesian methodology we would typically expect in favor of this polar system.
The first prototype that [André] built was a good proof of concept. A pen attached to a movable carriage on a single rotating arm produced passable drawings, but as all prototypes go this one needed some refinement. Limit switches at the ends of the table, as well as within the arm, served to orient the plotter so that it didn’t manually need to be zeroed out every time. A linear actuator was added to give finer control over the pen’s pressure on the table, and finally an encoder was added to the base of the plotter to more accurately correct positional errors in the rotating arm mechanism.
With everything said and done, the polar coordinate plotter seems to work just as well as its Cartesian cousins might, orienting it like this has some advantages as well. Specifically, it is more adapted to drawing curves or circles than an X-Y device might be able to, like we saw with this similar sand-drawing plotter. Also, if allowed to rotate its entire 360-degree reach instead of just the 90 degrees shown in the video, a machine like this could theoretically reach a wider workspace more easily than other plotters.
Over the years we’ve covered a lot of attempts by relatively clueless governments and politicians to enact think-of-the-children internet censorship or surveillance legislation, but there’s a law from France in the works which we think has the potential to be one of the most sinister we’ve seen yet.
It’s likely that if they push this law through it will cause significant consternation over the rest of the European continent. We’d expect those European countries with less liberty-focused governments to enthusiastically jump on the bandwagon, and we’d also expect the European hacker community to respond with a plethora of ways for their French cousins to evade the snooping eyes of Paris. We have little confidence in the wisdom of the EU parliament in Brussels when it comes to ill-thought-out laws though, so we hope this doesn’t portend a future dark day for all Europeans. We find it very sad to see in any case, because France on the whole isn’t that kind of place.
The early history of Linux is a rather murky period to most, long before the era of glitzy marketing and proclamations of ‘the Linux desktop’ being the next hot thing. This was also the era when the first Linux distributions were born, as the Linux kernel never came as a whole OS package – unlike the BSDs – which necessitated others to package it with the elements that make up kernel and user space, such as the GNU tools.
One of these original distributions was Debian, which this month celebrates its 30th birthday. Its entire history, starting with the initial 0.01 release is covered in great detail on the Debian website. After the first release of the Linux kernel in 1991, it would take until August of 1993 when [Ian Murdock] embarked on the Debian project, sponsored by the GNU Project of the Free Software Foundation. This was a pretty rough period, with much of 1994 spent figuring out the basics of the system, the package manager and establishing a release system. Continue reading “Looking Back On 30 Years Of Debian”→
The recent news that Russia’s Luna 25 Moon lander had made an unexpected lithobraking detour into the Moon’s surface, rather than the expected soft touchdown was met by a variety of responses, ranging from dismay to outright glee, much of it on account of current geopolitical considerations. Yet politics aside, the failure of this mission casts another shadow on the prospects of Russia’s attempts to revive the Soviet space program after a string of failures, including its ill-fated Mars 96 and Fobos-Grunt Mars missions, the latter of which also destroyed China’s first Mars orbiter (Yinghuo-1) and ignited China’s independent Mars program.
To this day, only three nations have managed to land on the Moon in a controlled fashion: the US, China, and the Soviet Union. India may soon join this illustrious list if its Chandrayaan-3 mission’s Vikram lander dodges the many pitfalls of soft touchdowns on the Moon’s surface. While Roscosmos has already started internal investigation, it does cast significant doubt on the viability of the Russian Luna-Glob (‘Lunar Sphere’) lunar exploration program.
Will Russia manage to pick up where the Soviet Union left off in 1976 with the Luna 24 lunar sample return mission?
Researchers at Carnegie Mellon University have shared a pre-print paper on generalized robot training within a small “practical data budget.” The team developed a system that breaks movement tasks into 12 “skills” (e.g., pick, place, slide, wipe) that can be combined to create new and complex trajectories within at least somewhat novel scenarios, called MT-ACT: Multi-Task Action Chunking Transformer. The authors write:
Trained merely on 7500 trajectories, we are demonstrating a universal RoboAgent that can exhibit a diverse set of 12 non-trivial manipulation skills (beyond picking/pushing, including articulated object manipulation and object re-orientation) across 38 tasks and can generalize them to 100s of diverse unseen scenarios (involving unseen objects, unseen tasks, and to completely unseen kitchens). RoboAgent can also evolve its capabilities with new experiences.
