LIDAR has gained much popularity as a means for self-driving cars to survey the space around them. At their most basic, LIDAR is a surveying method that uses lasers to paints the space around the sensors and assembles the distances measured from reflected light into a digital three-dimensional representation. That’s something that has quite a number of other applications, from surveying ancient ruins and rainforests from a bird’s eye view to developing 3D models of indoor spaces.
One fascinating use of LIDAR technology is to map out the routes inside caves, subterranean spaces that are seldom accessed by humans apart from those with specialized equipment and knowledge of how to safely traverse the underground terrain. [caver.adam] has been working on his Open LIDAR project for a few years using an SF30-B High Speed Rangefinder and laser device for a dual-system atop a gimbal with stepper motors for cave scanning.
Originally an entry in the 2016 Hackaday Prize, [Adam] has continued to work on the project. The result shown in the video below is a cheaper 3D LIDAR setup that works by rotating the laser distance module on 2 axes with a sensor centered at the center of rotation. It works for volumetric calculations, detects change over time, and identifies various water patterns and rocks on a surface map. Compared to notebooks, tape measures, and compasses, it’s certainly a step up in cave surveying technology.
Please join me in welcoming four new members to our crew. I published a post calling for applications almost two weeks ago. I wouldn’t say we were overwhelmed with applications. But I would say we were overwhelmed with qualified applicants. Hackaday writers need to be Jacks of all Trades in order to recognize and feature the best hacks from a wide range of disciplines. To this end we chose writers who have interests in areas what will complement those already represented by the team. I couldn’t be happier with the new contributors. Please join me in welcoming [James Hobson], [Todd Harrison], [Phillip Ryals], and [Adam Fabio]. They’ve already been hard at work dishing up fresh hacks, but you can learn more about their backgrounds by reading the biographies on our Staff Page.
You may have noticed a change this week. Although we’re an English language blog based in the United States, our statistics show readers throughout the world (in fact, almost a third of our writing team aren’t Americans). For this reason we changed our post scheduling earlier this week to a 24-hour cycle. This means more time between posts, and of course new posts being published in the middle of the night. Keep reading for a few more tidbits and a chance to give us your feedback.
[Chris] found a really cool pocket watch-style multimeter in a box of junk that was passed down from father to son. There aren’t any markings on it, so he’s looking for any information he can get on it. It’s a cool piece of vintage tech in any occasion; check out the pics he sent in below:
Here’s a fix for your illegal stuff
[Don] ‘acquired’ one of those China-only Raspberry Pis, but after plugging it in, only the power light would stay on. The fix, apparently, is putting these three files in the /boot folder of a Red Pi SD card.
Not a pocket watch
[Tom] picked up an old DC volt meter in an antiques shop. He quickly gutted it to make an analog meter display for his Raspberry Pi. There’s a few status lights to remind [Tom] of something he hasn’t figured out yet. Bonus points for a cheap buck boost converter, though.
Smashing monitors? Really?
The Meriden, CT hackerspace, the New England Society of Information and Technology, was vandalized last week. They’re dealing with some real punks here; their computers weren’t stolen, they were just smashed. NESIT is looking for donations (both money and equipment), so if you have a few monitors or old boxxen and live around there, consider donating them.
Help a guy out here.
[Jonathan] is a real cool dude that’s working on his master’s thesis on ways to build a sustainable company through the development of open source hardware. He wants you to take a survey. How do we know he’s cool? He had something posted on HaD back when we had the old black and white and scotch tape images.
[Steven Dufresne] does a lot of tinkering with solar-powered applications, a hobby which can be very time consuming if done right. One process he carries out whenever building a solar installation is creating a sun chart to determine how much (or little) sun the target area will get.
The process requires [Steven] to take elevation and Azimuth measurements of many different points, which often consumes about half an hour of his time. While taking measurements recently, he started thinking about how he could improve the process, and came up with a stellar solution that reduces the process down to a one-minute task.
In short, his shade finder tool uses a pulley, a pair of rollerblade wheels, and a pencil to accomplish a full shade survey in under a minute. The science behind the tool is best explained by [Steven], so be sure to check out his site for plenty of details and diagrams.
We have to say that we’re extremely impressed by his shade finder – hopefully his work can help others maximize the efficiency of their solar solutions.
Stick around after the jump to see a short video of the shade finder in action.
Take our reader survey. Do it. Do it right now. Do you think we should run more articles on the dietary needs of Llamas? Here is your chance to let us know. We got a lot of great feedback from [Jason]’s post, and now we’re ready for more. We’ve put together 10 quick questions that will help us get a feeling for what you want. We will be choosing 5 participants at random to give free t-shirts (the basic logo one).
Update: While we wait for our survey slave to get the changes made, please just put something in the fields that are mandatory(questions 7-9). Even if you put “no opinion”, we’ll get good info from the rest of the survey.
[Tom Wujec] explains how an astrolabe works and its importance in our technological development. He argues that an astrolabe was the world’s first “popular computer”. It measures the sky and that measurement can be used to tell time, survey land, and navigate a ship.
Astrolabes are built from three pieces and according to [Tom], educated children in the 1200’s would not just have been able to use one, but could build one as well. Electronics have certainly made our lives easier, but there’s something powerful about such a useful yet simple device.