lidar

68 Articles

Laser Scanning A Cave With Homebrew Gear

June 24, 2026 by 10 Comments

How do you measure the inside of a cave? You could do a bunch of hard work with classic surveying gear… or you could just use a laser scanner. [9nl] did the latter, with a scanning rig of his own creation.

The build is based around an Ouster VLP-16 mid-range lidar sensor. It shoots out pulses of light and measures how long it takes them to bounce back in order to determine the range of objects in the vicinity, and thus can be used to great effect for 3D scanning tasks. For [9nl], though, the sensor had a serious limitation. Since it only had a 40-degree field of view, it wasn’t ideal for the desired application of scanning a cave. However, by building a custom rig that could rotate the sensor, [9nl] ended up with a rig that could 3D scan an area through a full 360 degrees. There’s nothing wildly complex involved, just some good old mechanical engineering—putting the sensor on a shaft and spinning it with a belt drive. Then it’s just a matter of processing the data correctly. The hard part is then getting the rig in and out of the cave without breaking anything.

There are plenty of off-the-shelf 3D scanning solutions that can do this work, but few of them come cheap. Plus, rolling your own teaches you a great many things as you hone your solution to your particular needs. Video after the break.

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LiDAR Matrix Sensor Sees In 3D

May 14, 2026 by 6 Comments

[Mellow_Labs] picked up a few LiDAR matrix sensors and found them very exciting. While a normal time-of-flight sensor can accurately determine a range,  the matrix sensor is like an array of 64 sensors that can build a 2D map of distances from 2 cm to 3.5 m. [Mellow] wanted to add the sensor to his robot to help it see what was in front of it. You can see how it worked out in the video below.

The robot in question is Zippy, a 3D printed tank-like robot with an ESP32. By default, the robot requires control inputs, but using the sensor will enable autonomous operation. For good or ill, the sensor mounted to Zippy was seeing the floor with about half of the rows. That means about 50% of the data went to waste. However, we think having a robot be able to see the floor in front of it might be a good thing.

[Mellow] used an LLM to write most of the code, so there were a number of iterations required to get things working. This required decimating even more of the data from the sensor. Still, pretty impressive.

Want to learn more about ToF sensors? Or if you want to focus on the practical, there’s code you can borrow.

Continue reading “LiDAR Matrix Sensor Sees In 3D” →

Spatial Audio In A Hat

August 5, 2025 by 5 Comments

Students from the ECE4760 program at Cornell have been working on a spatial audio system built into a hat. The project from [Anishka Raina], [Arnav Shah], and [Yoon Kang], enables the wearer to get a sense of the direction and proximity of objects in the immediate vicinity with the aid of audio feedback.

The heart of the build is a Raspberry Pi Pico. It’s paired with a TF-Luna LiDAR sensor which is used to identify the range to objects around the wearer. The sensor is mounted on a hat, so the wearer can pan the sensor from side to side to scan the immediate area for obstacles. Head tracking wasn’t implemented in the project, so instead, the wearer uses a potentiometer to indicate to the microcontroller the direction they are facing as they scan. The Pi Pico then takes the LIDAR scan data, determines the range and location of any objects nearby, and creates a stereo audio signal which indicates to the wearer how close those objects are and their relative direction using a spatial audio technique called interaural time difference (ITD).

It’s a neat build that provides some physical sensory augmentation via the human auditory system. We’ve featured similar projects before, too.

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A Pi-Based LiDAR Scanner

April 18, 2025 by 30 Comments

Although there are plenty of methods for effectively imaging a 3D space, LIDAR is widely regarded as one of the most effective methods. These systems use a rapid succession of laser pulses over a wide area to create an accurate 3D map. Early LIDAR systems were cumbersome and expensive but as the march of time continues on, these systems have become much more accessible to the average person. So much so that you can quickly attach one to a Raspberry Pi and perform LiDAR imaging for a very reasonable cost.

This software suite is a custom serial driver and scanning system for the Raspberry Pi, designed to work with LDRobot LIDAR modules like the LD06, LD19, and STL27L. Although still in active development, it offers an impressive set of features: real-time 2D visualizations, vertex color extraction, generation of 360-degree panoramic maps using fisheye camera images, and export capabilities for integration with other tools. The hardware setup includes a stepper motor for quick full-area scanning, and power options that include either a USB battery bank or a pair of 18650 lithium cells—making the system portable and self-contained during scans.

LIDAR systems are quickly becoming a dominant player for anything needing to map out or navigate a complex 3D space, from self-driving cars to small Arduino-powered robots. The capabilities a system like this brings are substantial for a reasonable cost, and we expect to see more LiDAR modules in other hardware as the technology matures further.

Thanks to [Dirk] for the tip!

Time-of-Flight Sensors: How Do They Work?

January 20, 2025 by 15 Comments
With the right conditions, this tiny sensor can measure 12 meters

If you need to measure a distance, it is tempting to reach for the ubiquitous ultrasonic module like an HC-SR04. These work well, and they are reasonably easy to use. However, they aren’t without their problems. So maybe try an IR time of flight sensor. These also work well, are reasonably easy to use, and have a different set of problems. I recently had a project where I needed such a sensor, and I picked up a TF-MiniS, which is a popular IR distance sensor. They aren’t very expensive, and they work serial or I2C. So how did it do?

The unit itself is tiny and has good specifications. You can fit the 42 x 15 x 16 mm module anywhere. It only weighs about five grams — as the manufacturer points out, less than two ping-pong balls. It needs 5 V but communicates using 3.3 V, so integration isn’t much of a problem.

At first glance, the range is impressive. You can read things as close as 10 cm and as far away as 12 m. I found this was a bit optimistic, though. Although the product sometimes gets the name of LiDAR, it doesn’t use a laser. It just uses an IR LED and some fancy optics.

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Single Rotor Drone Spins For 360 Lidar Scanning

October 4, 2024 by 9 Comments

Multiple motors or servos are the norm for drones to achieve controllable flight, but a team from MARS LAB HKU was able to a 360° lidar scanning drone with full control on just a single motor and no additional actuators. Video after the break.

The key to controllable flight is the swashplateless propeller design that we’ve seen a few times, but it always required a second propeller to counteract self-rotation. In this case, the team was able to make that self-rotation work so that they could achieve 360° scanning with a single fixed LIDAR sensor. Self-rotation still needs to be slowed, so this was done with four stationary vanes. The single rotor also means better efficiency compared to a multi-rotor with similar propeller disk area.

The LIDAR comprises a full 50% of the drone’s weight and provides a conical FOV out to a range of 450m. All processing happens onboard the drone, with point cloud data being processed by a LIDAR-inertial odometry framework. This allows the drone to track and plan its flight path while also building a 3D map of an unknown environment. This means it would be extremely useful for indoor or underground environments where GPS or other positioning systems are not available.

All the design files and code for the drone are up on GitHub, and most of the electronic components are off-the-shelf. This means you can build your own, and the expensive lidar sensor is not required to get it flying. This seems like a great platform for further experimentation, and getting usable video from a normal camera would be an interesting challenge. Continue reading “Single Rotor Drone Spins For 360 Lidar Scanning” →

‘Radar’ Glasses Grant Vision-free Distance Sensing

January 19, 2024 by 7 Comments

[tpsully]’s Radar Glasses are designed as a way of sensing the world without the benefits of normal vision. They consist of a distance sensor on the front and a vibration motor mounted to the bridge for haptic feedback. The little motor vibrates in proportion to the sensor’s readings, providing hands-free and intuitive feedback to the wearer. Inspired in part by his own experiences with temporary blindness, [tpsully] prototyped the glasses from an accessibility perspective.

The sensor is a VL53L1X time-of-flight sensor, a LiDAR sensor that measures distances with the help of pulsed laser light. The glasses do not actually use RADAR (which is radio-based), but the operation is in a sense quite similar.

The VL53L1X has a maximum range of up to 4 meters (roughly 13 feet) in a relatively narrow field of view. A user therefore scans their surroundings by sweeping their head across a desired area, feeling the vibration intensity change in response, and allowing them to build up a sort of mental depth map of the immediate area. This physical scanning resembles RADAR antenna sweeps, and serves essentially the same purpose.

There are some other projects with similar ideas, such as the wrist-mounted digital white cane and the hip-mounted Walk-Bot which integrates multiple angles of sensing, but something about the glasses form factor seems attractively intuitive.

Thanks to [Daniel] for the tip, and remember that if you have something you’d like to let us know about, the tips line is where you can do that.