Adventures in Science: LIDAR

LIDAR, which is either a mashup of “laser” and “radar” or an acronym for “light detection and ranging” (depending on whom you ask), is the method of shooting a laser at an object and measuring the time it takes for that reflection to return to a receiver. With it, we can measure distances, determine the speed of moving cars, and map terrain. Here, we look at how LIDAR works and how it can be applied to robots to give them a means to detect objects.
Products shown:
LIDAR-Lite v3: www.sparkfun.com/products/14032
Scanse Sweep: www.sparkfun.com/products/14117

[@professordanfurmanek3732]

Retired University Astrophysics Professor: These truly wonderfully and very inspiring videos should be a complete 101 College Course! Wonderfully done, and truly the most inspiring teaching aid I've ever seen! Kudos, and please continue building your library for all the world to learn from!

[@georgejbaker]

great video, 10/10 for engagement factor.

[@johnmccormick2883]

Love the bloopers at the end ...

[@awesomelipe8396]

Awesome informative channel

[@sumedhburbure4173]

thank you for great quality content!

[@hugobracamontesbaltazar]

Nice video, very useful and funny.

[@IoTLearner]

Thank you Sparkfun

[@hongbinbin24]

Excellent!

[@IoTLearner]

This channel is much underrated!

[@Nishantmakadiya]

This video is underrated

[@gspecformations4459]

OMG what a conclusion: "'I wish you luck in your world domination plans!" lol!!

[@louiselu7500]

HI thanks for the video. Is there any demo or instructions about how to set it up (connections, software, etc) like what's shown in 4:24 of the video?

[@SoCalFreelance]

Photodiodes are also great for van Eck phreaking. I wonder if I can put that Scanse Sweep on my drone, combine the LIDAR data with GPS coords, and plot all the data to make a 3D point cloud of a large area?

[@jeffspaulding9834]

Good rule of thumb for Americans (and others blessed by the customary/Imperial system): The speed of light is about 1 foot / nanosecond. The propagation speed of electromotive force (that's voltage to you, bub) in copper varies depending on various factors, but inside a processor it's about 1/3 the speed of light and in very good cables it's about 9/10 the speed of light. Using those figures (and propagation delay numbers from datasheets), you can probably ballpark the time it takes between activating a signal to turn on a laser and getting a return back from your sensor. If you code the part where you turn on the laser and look for the return in assembly and count clock cycles, you can likely DIY your own crude LIDAR. Do a bit of calibration and you're set. Hey, found a new project to try. I've got some old CDROMs around here somewhere...

[@jfalbo]

great video I have a question. What happens when thousands of vehicles are on the road using different versions of lidar? won't those pulses of light interfere with each other's receivers? thanks

[@DennisCorey]

LIDAR-Lite signal processing technology isn't subject to interference from other LIDAR-Lites or other IR sources.

[@companymen42]

Would computer vision be a replacement for sweeping lidar or used in conjunction?

[@ivandenoia7950]

I'm having some troubles when trying to use a v3HP at an update rate of 1 Khz. Any helpful insight to share about that???

[@oxyo1805]

Nice video ! Where did you get your metalic part for prototype ?!

[@techmachito8031]

love it

[@cutefox8319]

Hello, i'm thinking if i could by one of these in the future, but i'm curious how well it work outside in a sunny day? I mean, LIDAR would be not faced directly to the sun, but would be looking around to detect obstacles.

[@madhaven694]

What's that software that plots the points to get the map, I mean the map of your room that's created

[@Zrzyck]

The light travels from laser to detector, what component can be used as detector? I guess it is not simple phototransistor, it is something similar to camera? Can I buy it somewhere i make my own LIDAR module?

[@calvinbarajas5144]

Thank you very much for this awesome video Shawn. I'm wondering if it would be possible to scan a dog and see only the body without the fur. Might you know if the LiDAR can penetrate fur or hair or clothing? Thank you very much!

[@Henry-sv3wv]

Just use a laser strong enough to burn away the fur. But may turn the dog into a fried chicken nuggets.

[@TechsScience]

I am willing to make it with the IR sensor module

[@wdiv]

I should have been impressed by LIDAR accuracy but instead my brain latched onto more proof that we landed on the moon lol

[@paulcurtis9380]

Could they be used to see inside someone’s home?

[@kavorka8855]

can anyone kindly tell me where can I get those really nice metal brackets with a lot of holes? any links? thanks! :DDDDDDD

[@ikaronumtemotronome]

2:36 I'm almost sure the average distance is twice this one, great vid though.

[@tombouie]

Thks, now I don't need a spinning LIDAR

[@nathanaelmukyanga3866]

Can Lidar penetrate underground?

[@walterharoldbishop]

how does a lidar measure 20ns? what kind of computer does that??

[@Belofsky1]

Cool, now only if I had $150 to spend on a single component.

[@arklanbk]

theyr 30$ now :)

[@electricwhirl5175]

​@@arklanbk where? :) link in the studio please for long-range 40m or similar :)

[@BLUYES422]

why not spin a mirror instead you would be able to spin it faster obviously. sampleing rate is still a thing but this is awsome tbvh maybe i get into robotics?

[@fusseldieb]

Cool ideia, with a 45° mirror we don't need electronics and cables attached after the motor...

[@helinick81]

hello ... how the hell would u divert reflected light back via the mirror? u people dont think do u

[@johnrainwater5249]

@@helinick81 you use a coated dichroic beamsplitting mirror you idiot

[@TonOfHam]

They bounced lasers off the moon before the reflector BS.

[@johngrannan]

Calc wrong: 3 x10(8) x 2 x 10(-9) / 2 = 0.3m

[@ShivarajD25]

He said 20ns (20x10^-9) or 2x10^-8

[@AbnormalWrench]

Finger quotes? Triggered!

[@marufhossain7487]

Lmfao ya good on world domination plan 😂

[@hansjansen317]

Light speed is slower in air

[@kerolox7929]

True, and these devices take this effect into account (else, they wouldn't work) by calibrating them, I'd imagine. Using the speed of light in vacuum is likely just to get the point across on how the LiDAR process works at a basic level

[@jeffspaulding9834]

Unless you're measuring things very far away, the (very slight) difference doesn't really matter. The margin of error in the measurements (if this video is to believed) is several orders of magnitude greater than the error caused by light being slowed by air.

[@TheLiasas]

i swear i read "shawn hymen"

[@mesillahills]

Perhaps the two most critical things, you failed to mention. First, laser beams bounce back in the direction they came from, not as if they hit a mirror. And second, single photons can be split up to 100 to 1 right now and still be effective. This makes for what is almost an unlimited potential in which a "driverless car" is the poster child. Also, "xyz" point clouds can be generated with simple photogrammetry which has overshadowed Lidar in some cases because it is so much cheaper. Try watching other people's videos.

[@Tadesan]

mesillahills I can't tell what you are talking about.

[@mesillahills]

I don't care. Do your own damned research and stop being so lazy. You don't learn anything about anything unless you put out some effort on your own.