Autopilot

21 Articles

A black, rectangular box is shown, with a number of waterproof screw connectors on the front.

A Ruggedized Raspberry Pi For Sailors

September 20, 2025 by 33 Comments

Nautical navigation has a long history of innovation, from the compass and chronometer to today’s computer-driven autopilot systems. That said, the poor compatibility of electronics with saltwater has consequently created a need for rugged, waterproof computers, a category to which [Matti Airas] of Hat Labs has contributed with the open-source HALPI2.

Powered by the Raspberry Pi Compute Module 5, the electronics are housed in a heavy duty enclosure made of aluminium, which also serves as a heat sink, and closes with a waterproof seal. It has a wide variety of external connectors, all likewise waterproofed: power, HDMI, NMEA 2000 and NMEA 0183, Ethernet, two USB 3.0 ports, and an external WiFi or Bluetooth antenna. The external ports are plugged into the carrier board by short extension cables, and there are even more ports on the carrier board, including two HDMI connectors, two MIPI connectors, four USB ports, and a full GPIO header. The case has plugs to install additional PG7 or SP13 waterproof connectors, so if the existing external connectors aren’t enough, you can add your own.

Besides physical ruggedness, the design is also resistant to electrical damage. It can run on power in the 10-32 volt range, and is protected by a fuse. A supercapacitor bank preserves operation during a power glitch, and if the outage lasts for more than five seconds, can keep the system powered for 30-60 seconds while the operating system shuts down safely. The HALPI2 can also accept power over NMEA 2000, in which case it has the option to limit current draw to 0.9 amps.

The design was originally created to handle navigation, data logging, and other boating tasks, so it’s been configured for and tested with OpenPlotter. Its potential uses are broader than that, however, and it’s also been tested with Raspberry Pi OS for more general projects. Reading through its website, the most striking thing is how thoroughly this is documented: the site describes everything from the LED status indicators to the screws that close the housing – even a template for drilling mounting holes.

Given the quality of this project, it probably won’t surprise you to hear this isn’t [Matti]’s first piece of nautical electronics, having previously made Sailor HATs for the ESP32 and the Raspberry Pi.

Getting Root Access On A Tesla

January 5, 2024 by 36 Comments

A growing number of manufacturers are locking perfectly good hardware behind arbitrary software restrictions. While this ought to be a bigger controversy, people seem to keep paying for things like printers with ink subscriptions, cameras with features disabled in firmware, or routers with speed restrictions, ensuring that this practice continues. Perhaps the most blatant is car manufacturers that lock features such as heated seats or even performance upgrades in the hopes of securing a higher price for their vehicles. This might be a thing of the past for Teslas, whose software has been recently unlocked by Berlin IT researchers.

Researchers from Technische Universität Berlin were able to unlock Tesla’s driving assistant by inducing a two-microsecond voltage drop on the processor which allowed root access to the Autopilot software. Referring to this as “Elon mode” since it drops the requirement for the driver to keep their hands on the steering wheel, they were able to access the full self-driving mode allowing autonomous driving without driver input. Although this might be a bad idea based on the performance of “full self-driving” in the real world, the hack at least demonstrates a functional attack point and similar methods could provide free access to other premium features.

While the attack requires physical access to the vehicle’s computer and a well-equipped workbench, in the short term this method might allow for owners of vehicles to use hardware they own however they would like, and in the long term perhaps may make strides towards convincing manufacturers that “features as a service” isn’t a profitable strategy. Perhaps that’s optimistic, but at least for Teslas it’s been shown that they’re not exactly the most secured system on four wheels.

Next-Gen Autopilot Puts A Robot At The Controls

August 25, 2023 by 19 Comments

While the concept of automotive “autopilots” are still in their infancy, pretty much any aircraft larger than an ultralight will have some mechanism to at least hold a fixed course and altitude. Typically the autopilot system is built into the airplane’s controls, but this new system replaces the pilot themselves in a manner reminiscent of the movie Airplane.

The robot pilot, known as PIBOT, uses both AI and robotics technology to fly the airplane without altering the aircraft. Unlike a normal autopilot system, this one can be fed the aircraft’s manuals in natural language, understand them, and use that information to fly the airplane. That includes operating any of the aircraft’s cockpit controls, not just the control column and pedal assembly. Supposedly, the autopilot can handle everything from takeoff to landing, and operate capably during heavy turbulence.

The Korea Advanced Institute of Science and Technology (KAIST) research team that built the machine hopes that it will pave the way for more advanced autopilot systems, and although this one has only been tested in simulators so far it shows enormous promise, and even has certain capabilities that go far beyond human pilots’ abilities including the ability to remember a much wider variety of charts. The team also hopes to eventually migrate the technology to the land, especially military vehicles, although we’ve seen how challenging that can be already.

Go Fly A Kite

November 13, 2022 by 17 Comments

Harvesting energy from the wind has been a commercially viable way of generating clean energy for around three decades now. Wind turbines are a reliable, proven technology but they do have some downsides, one of which is that since there’s more wind higher above the ground this usually means tall, expensive towers. There is a way around this problem, though, which is using kites to generate energy instead of a fixed turbine.

While kite generators aren’t a new idea, [Benjamin] has been working on this kite generator which has a number of improvements over existing kite generators. Like other kite generators, this one uses a tether to spin a generator which is located on the ground. But while this is similar to other kite systems, this prototype has a much simpler design and sweeps a much larger area while in flight. It also has an autopilot with multiple independent steering systems, which [Benjamin] says will allow it to stay in flight for months at a time provided there is enough wind. If there isn’t, it can land reliably, and launching it is relatively fast and simple as well.

While kites do have some obvious downsides compared to fixed turbines including a single point of failure at the tether and a large amount of cleared area to operate, they have plenty of advantages as well. They’re smaller, simpler, require no complicated yaw system, and can be easily maintained on the ground. In fact, it’s possible to build very simple kite generators out of nothing more than a hobby kite and some readily-available electrical components.

Continue reading “Go Fly A Kite” →

R2Home Is Ready To Bring Back Your High Altitude Payload

August 1, 2022 by 23 Comments

With high-altitude ballooning, you are at the mercy of the winds, which can move your payload hundreds of kilometers and deposit it in some inaccessible spot. To solve this [Yohan Hadji] created R2Home, an autonomous parachute-based recovery system that can fly a payload to any specified landing site within its gliding range.

We first covered R2Home at the start of 2021, when he was still in the early experimental phases, but the project has matured massively since then. It just completed its longest and highest test flight. Descending autonomously from a release altitude of 3500 m, with an additional radiosonde payload, it landed within 5 m of the launch point.

R2Home electronics with it's insulated enclosure
R2Home electronics with its insulated enclosure

R2Home can fly using a variety of steerable canopies, even a DIY ram-air parachute, as demonstrated in an earlier version. [Yohan] is currently using a high-performance wing for RC paragliders.

A lot of effort went into developing a reliable parachute deployment system. The main canopy is packed carefully in a custom “Dbag”, which is attached to a drogue chute to stabilize the system during free-fall and deploy the main canopy at a preset altitude. This is done with a servo operated release mechanism, while steering is handled by a pair of modified winch servos intended for RC sailboats.

All the electronics are mounted on a stack of circular 3D printed brackets which fit in a tubular housing, bolted together with threaded rods. With the help of a design student [Yohan] also upgraded the simple tube housing to a lockable, foam-insulated design to help it handle temperatures at high altitudes.

The flight main flight computer is a Teensy 4.1  plugged into a custom PCB to connect all the navigation, communication, and flight systems. The custom Arduino-based autopilot takes inputs from a GPS receiver, and pilots the system to the desired drop zone, which it circles until touchdown.

The entire project is extremely well documented, and all the design files and code are open source and available on Github. Continue reading “R2Home Is Ready To Bring Back Your High Altitude Payload” →

Taking Reverse Engineering To The Skies: Cheap Drone Gets PX4 Autopilot

April 24, 2021 by 3 Comments

Sometimes bad software is all that is holding good hardware back. [Michael Melchior] wanted to scavenge some motors and propellers for another project, so he bought an inexpensive quadcopter intending to use it for parts. [Michael] was so surprised at the quality of the hardware contained in his $100 drone that he decided to reverse engineer his quadcopter and give the autopilot firmware a serious upgrade.

Upon stripping the drone down, [Michael] found that it came with a flight management unit based on the STM32F405RG, an Inertial Measurement Unit, magnetic compass, barometric pressure sensor, GPS, WiFi radio, camera with tilt, optical flow sensor, and ultrasonic distance sensor, plus batteries and charger! The flight management unit also had unpopulated headers for SWD, and—although the manufacturer’s firmware was protected from reading—write protection hadn’t been enabled, so [Michael] was free to flash his own firmware.

We highly recommend you take a look at [Michael]’s 10 part tour de force of reverse engineering which includes a man-in-the-middle attack with a Raspberry Pi to work out its WiFi communication, porting the open-source autopilot PX4 to the new airframe, and deciphering unknown serial protocols. There are even amusing shenanigans like putting batteries in the oven and freezer to help figure out which registers are used as temperature sensors. He achieves liftoff at the end, and we can’t wait to see what else he’s able to make it do in the future.

Of course, [Michael] is no stranger to hacking imported quadcopters, and if you’re interested in PX4 but want something quieter than a quadcopter, take a look at this autopilot-equipped glider.

GPS Guided Parachutes For High Altitude Balloons

January 7, 2021 by 32 Comments

Most amateur high altitude balloon payloads descend back to earth with a simple non-steerable parachute and can land hundreds of kilometers from the launch site in inaccessible areas. [Yohan Hadji] experienced this first-hand during a balloon launch conducted by his high school, which inspired him to R2Home, a GPS-guided parachute recovery system.

A Teensy runs the show, and controls a pair of sail winch servos pulling the brake lines

[Yohan]’s first challenge was to create a steerable parachute that can deploy reliably, so he started doing tests with a borrowed scale model paragliding wing. He quickly learned that a canopy aspect ratio of below two was needed for reliable deployment, so he started sewing his own canopies. Steering a parachute involves pulling on a pair of brake lines, one for each side of the parachute. A control stroke of about 20 cm was required, and [Yohan] found that RC sailboat winch servos work perfectly for this application. The entire system is designed to fit in a 7×40 cm tube, and the parachute is deployed with the help of a small drogue chute and a servo-operated release mechanism.

[Yohan] is working on a custom flight controller, built around a Teensy 4.1, GPS receiver, and digital compass. A possible alternative is Ardupilot, which we’ve seen used on several autonomous drones, gliders, and rovers. While this system might not be possible to return to the launch point, it could certainly close the gap, and land safely in a designated area.

So far [Yohan] has done a series of test drops from a drone at low altitude to test deployment and steering, using an RC controller. The project is open source, and the mechanical design files and control code is up on GitHub. As with most 16-year-olds, [Yohan]’s resources are limited, so feel free to drop him some financial help on the R2Home GoFundMe page. See the videos after the break for a development montage and project presentation. Continue reading “GPS Guided Parachutes For High Altitude Balloons” →