I built an ROV to solve missing person cases

Although it has already been said close to 137 times, this is the best read I&#x27;ve had this year, although that&#x27;s likely an understatement. I love the hacking spirit and how they always settle on the simplest solution, whether from a technical standpoint or an investigative one.<p>Great job, and I&#x27;m glad they got the recognition they deserve. Shout out to the Finnish police as well for not letting their ego interfere with information brought to them by a couple of random amateurs. This should be the norm, but sadly it isn’t.

This is amazing. A Finnish man gets curious about a missing persons case. He does some great detective work, and builds an ROV with side scanning sonar and video. The outcome, with some help from his brother, is just spectacular. I couldn&#x27;t stop reading!

Joining the chorus to say that this is one of the greatest articles I’ve read. I love everything about it. From the hacker spirit to the investigative reasoning to the little observations made during the process like what could be considered a weapon according to regulations and how Covid affected costs of different items and when to consider o ring size in the planning. Love love love it.<p>My favorite line had to be this though.<p>&gt; The first prototype didn’t look like much but the mental effect was enormous. Now there was at least something to show and improve.<p>worthy of being printed and framed.

This was incredibly well written and the project itself was super cool to see come together. I worked on building UAV&#x27;s in University but seeing the unique challenges with dealing with water from a signals perspective was really intriguing.<p>Good luck with any future cases and can&#x27;t wait to see what upgrades you make!

The article doesn&#x27;t say so, but some web search and deepl.com translation makes it sound like the second missing person may have died by suicide. When they first found the sunken car, they wondered (presuming that the car had gone off the road by accident) how the heck the car had ended up so far out into the water. The answer might be that it didn&#x27;t fall off the road, but rather was driven off at high speed on purpose, with the express intention of making it hard to find afterwards. :(

As you can see, this is long:<p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-02&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-02&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-03&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-03&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-04&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-04&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-05&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-05&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-06&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-06&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-07&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-07&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-08&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-08&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-09&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-09&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-10&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-10&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-11&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-11&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-12&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-12&#x2F;</a><p><a href="https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-13&#x2F;" rel="nofollow">https:&#x2F;&#x2F;suanto.com&#x2F;2024&#x2F;06&#x2F;06&#x2F;the-time-I-built-an-ROV-13&#x2F;</a><p>But we got an email from a (unrelated) user saying it&#x27;s good, so I&#x27;ve put it in the SCP (<a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=26998308">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=26998308</a>).<p>ROV = remotely operated vehicle btw

This is the best thing I&#x27;ve read on HN in months.<p>Hats off to the author and his willingness to combine his curiosity and skillset in such a rewarding way. We need more people like him.

One of the best articles I have read for years. It&#x27;s easy to underestimate how difficult it is to make things &quot;just work&quot; in the first trial. I really envy the author&#x27;s ability to plan for known and unknown situations. Marvelous job!

&gt; So where was he going? I saw two possibilities: either to Tikkakoski to visit his ex-girlfrind he was on the phone with or; just to drive around with a new powerful car, to shake off the heated phone call.<p>I don&#x27;t understand how suicide isn&#x27;t at the top of the list here. He was obviously very upset emotionally. He didn&#x27;t care for his belongs other than his phone. He didn&#x27;t care to steal someone&#x27;s car or answer for it. He never shows up anywhere.

Absolutely fantastic read. The author got nerd-sniped HARD by these missing-person cases and his approach and accomplishments are inspiring, to say the least. Very well done!

The team at CPSdrone (3D printed submersibles) made a very similar project to hunt for and identify a sunken plane: <a href="https:&#x2F;&#x2F;youtu.be&#x2F;QnBfJzApJMg?si=vFGqMrqZOgFXMAoV" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;QnBfJzApJMg?si=vFGqMrqZOgFXMAoV</a><p>They also used an ArduRover powered catamaran and the same brand Sonar, but made a smaller deployable ROV.

I love these long-form build logs.<p>I just started reading, and I am making the faux-pas of commenting before finishing.<p>But, I&#x27;m wondering what the challenges are of automating the ROV to map a body of water&#x27;s floor in a pattern. like a grid pattern, or whatever is most efficient.<p>At first I was thinking currents would cause displacement. but can&#x27;t we sense the current moving us in undesirable ways and correct with thrusters?<p>And then I thought.. do lakes have currents? Do they have tides? can a ROV sense the boundary of a lake?<p>just further down the rabbit hole, realizing how little I&#x27;ve learned about the natural environment!

I&#x27;m not even that impressed by the DIY tech but by the incredible detective insight this man seems to have to just guess three likely sites and be correct and not having to search half of Finland.

I throughly enjoyed reading the entire story. However I found it strange he sort of ended with “they searched for the car and asked us to leave.” The first one they got thanked profusely. But at no point did the author ever claim to have definitively found the car or the body. It’s humble but almost oddly so. Anyway great story.

Without a doubt the most interesting article I&#x27;ve read here. If they didn&#x27;t sink in a car, am I correct to assume the bodies would have surfaced eventually?

I didn&#x27;t expect to read this whole piece but it was completely gripping. Outstanding work and a really great write up.

I loved the project!! I also like how “messy” the room is, reminded me of my room (1) when I was working from home years ago.<p>I haven’t read the whole thing but I will, however, I did go through the technical details, some notes:<p>&gt; This model didn’t have a long enough range on the analog sticks<p>I see you are using Radiomaster tx16s, pro tip: You can use ELRS 2W model on BOTH transmitter and the receiver, don’t use the typical receiver unit, use another transmitter and flash it as a receiver, and you would have 2W on both sides, preferably 900mhz not 2.4ghz, and you would’ve hundreds of kilometers of range and strong obstacles penetration.<p>For the camera and the tether, technically you can get rid of the tether and use wireless comms, but probably what you did is the best for bucks solution.<p>Overall, looks great!<p>(1) <a href="https:&#x2F;&#x2F;tamim.io&#x2F;professional_projects&#x2F;nerds-heavy-lift-drone-with-low-latency-command-and-control-over-cellular-5g-and-4k-video-stream-in-realtime&#x2F;nerds_33.jpg" rel="nofollow">https:&#x2F;&#x2F;tamim.io&#x2F;professional_projects&#x2F;nerds-heavy-lift-dron...</a>

The quest he mentions as inspiration - Tom Mahood&#x27;s &quot;The Hunt for the Death Valley Germans&quot; - is a fascinating read and worth your time.<p><a href="https:&#x2F;&#x2F;www.otherhand.org&#x2F;home-page&#x2F;search-and-rescue&#x2F;the-hunt-for-the-death-valley-germans&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.otherhand.org&#x2F;home-page&#x2F;search-and-rescue&#x2F;the-hu...</a><p>I first read it seven years ago and similar to the author, it inspired me to join my local Search &amp; Rescue team which has been incredibly rewarding. I highly recommend doing that to anyone who wants to combine a love of the outdoors, specialized skills, serving the community, and helping people in their worst moments. (And doesn&#x27;t mind getting up at 3am in pouring rain and going out and pushing through dense underbrush for hours!)

While I&#x27;m sure they did this to try to combine their talents and interests with altruism, what they got out of the end of that was both of those but also a legacy.<p>Most of us only wish we could tell stories like that as a result of the technical work we do.

Posts like these really get down to the essence of Hacker News for me. Doing amazing, previously impossible things through sheer nerdy effort. What a deeply impressive story!

having built autonomous ROVs in college, i&#x27;m absolutely astonished at what this person accomplished essentially on their own. they are so finicky and piloting them is a whole skill set on its own.<p>and, what perseverance; it really did read like a detective story and what a good job distilling the cases down to their basics.<p>what a cool read and an absolute triumph of an accomplishment.

These articles are the reason i check hacker news every day. What an amazing find, thanks for sharing - I love these articles, especially since Tom Mahood&#x27;s website has been kind of dried up (otherhand).

I recall that the guys who started OpenROV did so because they wanted to explore a flooded cave that was rumored to have stolen gold in it.

Awesome story! The first case had me thinking &quot;These nerds are wasting their time...why not just a gopro on a long stick&quot;. But hearing about the details of the second story, it would have been impossible without the sonar and ROV!

Loved the writing style, the technical description, the links to info and also the actual missing person cases.<p>This would make for a great TV series ;-)

This is sort of an aside, I hope no one hates it.<p>I’ve spread myself so thin over the years that I find it hard to get excited about things.<p>If this is your mission, don’t quit. Do it. Second chances are consolation prizes, and a noble cause may only present once.

Frankly, my takeaway here is that police detectives in Finland are poorly trained and not very good at analytical thinking.<p>In the first case, if they&#x27;d reasoned things out like the author did, they could have simply had someone walk alongside the road that he was likely to be on, they would have seen pretty obvious evidence of damage to the ground &#x2F; foliage, gone for a closer look, and seen all the broken car bits.<p>Add to that the author getting the cold shoulder when he called the police and said &quot;hey, can you send a detective over, I found a car in the water and it matches the vehicle in the missing person case nearby&quot;, and they basically told him to fuck off - and then finally showed up when the fire brigade pestered them a second time.

I would suggest defining any acronyms in the title of an article in the introduction section of the article.<p>Had to get to PART 6 to answer my first question: What is an &quot;ROV&quot;?<p>&quot;The solution was to use an ROV, Remote Operated Vehicle &quot;

&gt; “ROV” stands for remotely operated vehicle

recent HN discussion on an earlier SAR that was the spark for this glorious mad Finn:<p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=34676129">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=34676129</a>

i don&#x27;t usually read long articles, especially paginated ones. but this one got my attention and I don&#x27;t regret it. such a nice mix of tech and suspense mystery thriller. thanks!

Fascinating but sad reading. Don&#x27;t drink and drive.

&#x2F;? underwater infrared camera: <a href="https:&#x2F;&#x2F;www.google.com&#x2F;search?q=underwater+infrared+camera" rel="nofollow">https:&#x2F;&#x2F;www.google.com&#x2F;search?q=underwater+infrared+camera</a><p>r&#x2F;rov: <a href="https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;rov&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;rov&#x2F;</a><p>Bioradiolocation: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Bioradiolocation" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Bioradiolocation</a><p>FMCW: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Continuous-wave_radar" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Continuous-wave_radar</a><p>mmWave (60 Ghz) can do heartbeat detection above water FWIU. As can WiFi.<p>mmwave (millimeter wave), UWA (Underwater Acoustic)<p>Citations of &quot;Analysis and estimation of the underwater acoustic millimeter-wave communication channel&quot; (2016) <a href="https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=8297460493079369585&amp;as_sdt=5,43&amp;sciodt=0,43&amp;hl=en" rel="nofollow">https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=8297460493079369585...</a><p>Citations of &quot;Wi-Fi signal analysis for heartbeat and metal detection: a comparative study of reliable contactless systems&quot; <a href="https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=3926358377223165726&amp;as_sdt=5,43&amp;sciodt=0,43&amp;hl=en" rel="nofollow">https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=3926358377223165726...</a><p>&#x2F;? does WiFi work underwater? <a href="https:&#x2F;&#x2F;www.google.com&#x2F;search?q=does+wifi+work+underwater" rel="nofollow">https:&#x2F;&#x2F;www.google.com&#x2F;search?q=does+wifi+work+underwater</a><p><a href="https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=13087602574164936719&amp;as_sdt=5,43&amp;sciodt=0,43&amp;hl=en" rel="nofollow">https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=1308760257416493671...</a> ... &quot;Environment-independent textile fiber identification using Wi-Fi channel state information&quot;, &quot;Measurement of construction materials properties using Wi-Fi and convolutional neural networks&quot;<p>&quot;Underwater target detection by measuring water-surface vibration with millimeter-wave radar&quot; <a href="https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=17107681556243877942&amp;as_sdt=5,43&amp;sciodt=0,43&amp;hl=en" rel="nofollow">https:&#x2F;&#x2F;scholar.google.com&#x2F;scholar?cites=1710768155624387794...</a> :<p>&gt; UWSN (Underwater Sensor Network)<p>I&#x27;m reminded of Baywatch S09E01; but those aren&#x27;t actual trained lifeguards. The film Armageddon works as a training film because of all of the [safety,] mistakes: <a href="https:&#x2F;&#x2F;www.google.com&#x2F;search?q=baywatch+s09e01" rel="nofollow">https:&#x2F;&#x2F;www.google.com&#x2F;search?q=baywatch+s09e01</a>

An incredible read! Thank you so much. It even has the famous Finnish humility downplaying his huge achievements

The author clearly reads HN or used to. I’m curious if he plans on pursuing this further. Sounds like the last investigation wrapped in 2021 and he may have even gotten a cash injection to upgrade some of his kit. The last update kind of leaves you hanging!

Amazing read! These ROVs should be massed produced and distributed to the police everywhere..

Reading this kinda makes one question the incentives and competency of government investigation programs. All they did was ask “given the reliable info, where could the car be”? And they display better deductive reasoning than professional investigators, and achieve results with a budget of pennies. I know you can’t win them all but still I’m a little disillusioned and question whether investigation agencies should be publicly funded and operated when I read these type of stories.

This is like a little humble and decent version of those &quot;Adventures with Purpose&quot; guys on YT. Nice work!

This series of articles is genuinely thrilling to read. What a fantastic and truly worthwhile bit of detective work. Very well written up.

Wow, what a great story! Really inspiring too, well done and well written.

Does anyone have the Google maps location where these two cars were found? Trying to see if they are visible there

This is quite honestly one of the most phenomenal reads I have had on HackerNews. From the technical detail to the personal investigation, this truly shows how much one person can accomplish with discipline and a goal. Kudos to you sir!

This was absolutely captivating! Better than any book I’ve read lately!

Amazing. Exactly the type of content that I come to HN for.

Just make a netflix documentary already. Amazing material.

Excellent writing. The next ROV should have a magnetometer.

The technical details are in part 4 and 6.

This is so cool. I hope he kept at it.

OP should have not felt bad about contacting family members and done it to yield more information to help them in their cases.

And now I have a new obsession: building an boat or underwater ROV with a camera and a sonar

Awesome Read.

I built an RV to increase missing person cases

Amazing