Lunar Lander Game Asks You To Write A Simple Autopilot

August 16, 2024 by Donald Papp 28 Comments

Everyone likes a good lunar landing simulator, and [Dominic Doty] wrote a fun take on the idea: your goal is to write an autopilot controller to manage the landing. Try it out!

Virtual landers are far cheaper than real ones, thank goodness.

[Dominic] was inspired in part by this simple rocket landing game which is very much an exercise in reflex and intuition, not to mention being much faster-paced than the classic 1979 video game (which you can also play in your browser here.)

[Dominic]’s version has a similar classic look to the original, but embraces a more thoughtful approach. In it, one uses plain JavaScript to try to minimize the lander’s angle, velocity, and angular velocity in order to land safely on the generated terrain.

Want to see if you have the right stuff? Here’s a direct link to Lunar Pilot. Don’t get discouraged if you don’t succeed right away, though. Moon landings have had plenty of failures, and are actually very hard.

The Lunar Odyssey: Moon Landings From The 1960s To Today’s Attempts

March 20, 2024 by Maya Posch 21 Comments

With the recent string of lunar landing attempts, it’s interesting to consider how much things have changed – or stayed the same – since the first soft landing attempts in the 1960s with the US Ranger and USSR Luna landers. During the 1950s the possibility of landing a spacecraft on the Moon’s surface was investigated and attempted by both the US and USSR. This resulted in a number of lunar lander missions in the 1960s, with the US’s Ranger 3 and 5 missing the Moon, Ranger 4 nearly missing it but instead crashing into the far side of the Moon, and eventually the USSR’s Luna 9 making the first touchdown on the lunar surface in 1966 after a string of USSR mission failures.

What’s perhaps most interesting was how these first US and USSR spacecraft managed to touch down, with Luna 9 opting to inflate a landing airbag and bounce until it came to a halt. This approach had doomed Luna 8, as its airbag got punctured during inflating, causing a hard crash. Meanwhile the US’s Surveyor 1 was the first US spacecraft to land on the Moon, opting to use a solid-fuel retrorocket to slow the craft down and three liquid-fueled vernier thrusters to prepare it for a drop down from 3.4 meters onto the lunar surface.

Now, nearly 60 years later, the landers we sent regularly make it to the lunar surface, but more often than not end up crashing or toppling over into awkward positions. How much have lunar landings really changed?

Continue reading “The Lunar Odyssey: Moon Landings From The 1960s To Today’s Attempts” →

Intuitive Machines’ Nova-C Makes It To The Lunar Surface In US Return After Half A Century

February 23, 2024 by Maya Posch 57 Comments

Intuitive Machines’ first mission (IM-1) featuring the Nova-C Odysseus lunar lander was launched on top of a SpaceX Falcon 9 on February 15th, 2024, as part of NASA’s Commercial Lunar Payload Services (CLPS). Targeting a landing site near the lunar south pole, it was supposed to use its onboard laser range finders to help it navigate safely for a soft touchdown on the lunar surface. Unfortunately, it was this component that was found to have malfunctioned as the spacecraft was already in lunar orbit. Fortunately, there was a workaround. By using one of the NASA payloads on the lander, the Navigation Doppler Lidar (NDL), the mission could continue.

Perhaps unsurprisingly, the use of the NDL as a fallback option was considered before launch, and since its functionality overlaps with that of the primary laser range finders of Nova-C, it was pressed into service with a new configuration uploaded by IM operators back on Earth before Nova-C committed to a landing burn. Then, on February 22nd, the spacecraft began its descent to the surface, which also involved the Eaglecam payload that was designed to be released before snapping a self-portrait of the lander as it descended.

Continue reading “Intuitive Machines’ Nova-C Makes It To The Lunar Surface In US Return After Half A Century” →

Vulcan Nails First Flight, But Peregrine Falls Short

January 9, 2024 by Tom Nardi 24 Comments

For those with an interest in the history of spaceflight, January 8th promised to be a pretty exciting day. Those who tuned into the early morning live stream were looking forward to seeing the first flight of the Vulcan Centaur, a completely new heavy-lift booster developed by United Launch Alliance. But as noteworthy as the inaugural mission of a rocket might be under normal circumstances, this one was particularly special as it was carrying Peregrine — set to be the first American spacecraft to set down on the lunar surface since the end of the Apollo program in 1972.

Experience has taught us that spaceflight is hard, and first attempts at it doubly so. The likelihood of both vehicles performing as expected and accomplishing all of their mission goals was fairly remote to begin with, but you’ve got to start somewhere. Even in the event of a complete failure, valuable data is collected and real-world experience is gained.

Now, more than 24 hours later, we’re starting to get that data back and finding out what did and didn’t work. There’s been some disappointment for sure, but when everything is said and done, the needle definitely moved in the right direction.

Continue reading “Vulcan Nails First Flight, But Peregrine Falls Short” →

Making A Kid-Scale Apollo 11 Lunar Lander

August 5, 2023 by Donald Papp 21 Comments

If you’d like to see what goes into making a 1/3-scale Apollo 11 Lunar Module, [Plasanator]’s photos and build details will show off how he constructed one for a kid’s event that was a hit!

The photo gallery gives plenty of ideas about how one would approach a project like this, and readers will surely appreciate the use of an old frying pan as a concrete mold to create the lander’s “feet”. Later, a little paint makes the frying pan become a pseudo-antenna mounted on the lander’s exterior.

Inside, the lander has a control panel with a lot of arcade-style buttons and LED lighting. It’s pretty simple stuff, but livens things up a lot. Bright red lighting for the engine combined with a couple of slow strobe lights really makes it come alive in the dark. The gold foil? Emergency thermal blankets wrapped around the frame.

We happen to have the perfect chaser for this kid-scale lunar module: the Apollo 11 moon landing, recreated with animatronics and LEGO.

Continue reading “Making A Kid-Scale Apollo 11 Lunar Lander” →

The Glitch That Brought Down Japan’s Lunar Lander

June 3, 2023 by Matthew Carlson 36 Comments

When a computer crashes, it usually doesn’t leave debris. But when a computer happens to be descending towards the lunar surface and glitches out, that’s a very different story. Turns out that’s what happened on April 26th, as the Japanese Hakuto-R Lunar lander made its mark on the Moon…by crashing into it. [Scott Manley] dove in to try and understand the software bug that caused an otherwise flawless mission to go splat.

The lander began the descent sequence as expected at 100 km above the surface. However, as it descended, the altitude sensor reported the altitude as much lower than it was. It thought it was at zero altitude once it reached about 5 km above the surface. Confused by the fact it hadn’t yet detected physical contact with the surface, the craft continued to slowly descend until it ran out of fuel and plunged to the surface.

Ultimately it all came down to sensor fusion. The lander merges several noisy sensors, such as accelerometers, gyroscopes, and radar, into one cohesive source of truth. The craft passed over a particularly large cliff that caused the radar altimeter to suddenly spike up 3 km. Like good filtering software, the craft reasons that the sensor must be getting spurious data and filters it out. It was now just estimating its altitude by looking at its acceleration. As anyone who has tried to track an object through space using just gyros and accelerometers alone can attest, errors accumulate, and suddenly you’re not where you think you are.

We know what you’re thinking: surely they would have run landing simulations to catch errors like these? Ironically they did, it’s just that after the simulations were run, the landing site for Hakuto-R was changed. Unfortunately, nobody thought to re-run the simulations, and now the Moon has a new lawn ornament,

We’ve previously written about why lunar landings are so hard. While knowing what led to the crash will hopefully prevent a similar fate for future missions, the reality is that remotely landing a robot on a dusty world without the help of GPS is fiendishly difficult and likely will be for some time.

Continue reading “The Glitch That Brought Down Japan’s Lunar Lander” →

Hackaday Podcast 068: Picky Feeders, Slaggy Tables, Wheelie Droids, And Janky Batteries

May 22, 2020 by Mike Szczys 2 Comments

Hackaday editors Elliot Williams and Mike Szczys ride the rails of hackerdom, exploring the sweetest hacks of the past week. There’s a dead simple component feeder for a pick and place (or any bench that hand-stuffs SMD), batteries for any accomplished mixologist, and a droid build that’s every bit as cool as its Star Wars origins. Plus we gab about obsolescence in the auto industry, fawn over a frugal microcontroller, and ogle some old iron.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)