Sketchfab, 3D reconstruction and the Bomb squad - A true story from Scotland

Sketchfab community member Chris Harvey was in for an exciting day when he visited the beach earlier in the week. Little did he know it would involve the use of 3D scanning, Sketchfab and the bomb squad! Read his report.

Well what a day it turned out to be! Not often do you have a chance to actually be at the centre of something so important where you can clearly make a difference.

Hi, I am Chris and I run a thermal imaging services company called Leak Heat based here in sunny Scotland just north of Aberdeen with headquarters in Cruden Bay. Our thermal imaging services took a unique opportunity some time ago, when 3D modelling was introduced to our industrial clients as an add-on in the place of other scanning techniques

But it’s not often you get to prove what you preach yourself. Here’s the story:

After some regular sightings of newborn seal pups in the area we decided to take our thermal imaging equipment on a little adventure to the local beach at Cruden Bay to do some environmental scanning. Dogs and newborn seals don’t really like each other and it’s better to know if there are any newborns at this time of year to warn the local dog walkers before they venture far up the beach.

“Obviously, now in hindsight, the next stage may not have been done, but I was intrigued by what I had found”

Having wandered through the golf course to access the beach and scanning everything with the thermal equipment, a suspicious thermal signature was seen on our T420 thermal camera. It was odd as there shouldn’t have been anything like that there. So thought I’d take a look. Having climbed down the dunes, fought through the long grass I made it to the bottom of a small inlet and was greeted by a 75% buried round lump of metal. It was rusty and big, the thermal camera had picked up something I thought to myself.

Obviously, now in hindsight, the next stage may not have been done, but I was intrigued by what I had found. So I began doing some very careful excavation in the sand around the object.

But it quickly dawned on me that this thing was about 75cms diameter and solid metal, and solid means heavy. Having uncovered about half of it, there was a clear hole in one end. At this point I thought “redundant fishing gear”. But I also remember from working offshore in the underwater oil and gas sector that UXOs (unexploded ordnance) are not uncommonly found in the North Sea. So I decided to photograph the item with the DSLR I had with me and model it to see if there was anything hiding in the images I could use to define what we had here. I remoted into one of our big PCs and sent the images to the PC for post processing, knowing the images would be uploaded ready for modelling by the time I got back, saving some time.

The rest of the operation was quite simple. The 3D reconstruction was complete within an hour and I was looking at something that was very much “bomb” like. I took measurements from the model, approximated the weight, looked at the location with reference to one of the Forties pipelines that comes into Cruden Bay and extracted the GPS data. All ready to phone the police.

“(I) gave the link to the model straight to the control room to have a look at. Within 10 minutes I had a knock at the door…by two policemen!”

I spoke with the a call handler who took the usual information and asked “So what have you found on the beach, Mr. Harvey?” I said “A big round metal sphere”. Just with that she said “Oh, right ok, stay on the line I am flashing this to the main control unit”. The rest of the conversation was quite structured and quick. We ended the call, having been able to upload the model to Sketchfab at the start of the conversation and gave the link to the model straight to the control room to have a look at. Within 10 minutes I had a knock at the door…by two policemen! Now that was quick! They wanted to know more detail about the object, my whereabouts etc., and then asked me to accompany them to the site on the beach. Now it’s not often you get offered a ride in a police car voluntarily. It was quite surreal, getting in the back of the police car and driving to the golf course and then down and through the golf course, passing golfers on the 9th hole. I thought to myself “What are they thinking now?”

“I showed him on my mobile phone! Technology in action I thought to myself.”

Time passed quite quickly: the police and I went to the location and I showed them the item from a distance and a call from the control room then confirmed that they thought it was a sea mine so upgraded it to a UXO. More and more people were looking at the model on the internet, unbeknown to me, as I was onsite with the two policemen.

An exclusion zone around the object was placed of 50 meters and then to 100 meters, meaning part of the beach was closed off and a very quiet evacuation of the golfers further down the links. The manager of the golf club turned up and wanted to see the model, so I showed him on my mobile phone! Technology in action I thought to myself.

Now the end of the story is coming, but before that, the Royal Navy bomb disposal unit from the Scottish Borders had been mobilised and were on route, but they were able to see the model I had put on sketchfab, maneuver themselves round it and were remotely guiding the police on the ground in conducting an assessment of the sea mine looking for further confirmation on its actual type, etc at the same time. But, luckily I suppose, the object was determined to be a bobbin from some redundant trawl gear. Not particularly an anti climax, but the start of something much better.

Now, just because it turned out not to be a bomb is one thing, but the whole scenario of events proves to me the validity of technology in use today as a tool in the box for lots and lots of different eventualities. The following is a summary from my point of view:

1. Thermal imaging equipment aided identifying something of unknown origin at distance, which was worth investigating.
2. The ability to take crisp clear photographs quickly (bracketed for HDR) really aided in capturing lots of detail for the ability to model.
3. Using a mobile phone to remote in and uploading images directly to a PC for processing
4. Having the right expertise and right equipment to then turn around a 3D model with dimensional accuracy in less than an hour and have it hosted online, is something very special.
5. Remote viewing of the 3D reconstruction on sketchfab over the internet allowed others access to make early safety critical decisions, possibly saving lives as well as time until the experts can make their decisions.
6. The model had enough detail to allow experts to navigate around it and allowed a margin of safety to the officers to get hands on and make assessments based on the bomb disposal personnel’s experience.

What a thing!!! The times we have all looked at a photo and wanted to see a little more round the the side of something only to miss the critical bit in the image. Now with 3D reconstruction, you don’t have to worry about a missed bit, it’s all there and you control your view. All of this above is very powerful stuff, only a few years ago all of the above would have cost the UK taxpayer a significant amount of money and time to assess the situation which, in this case, was a non lethal event.

The possibilities are endless in our eyes at Leak Heat after this event: radio interviews, publications in newspapers, and positive feedback from members in industry, who are definitely coming round to our way of thinking that 3D reconstruction from imagery is a tool and not a gimmick and has its place now firmly within anyone’s grasp. You can do it from the air via any method you wish to use, terrestrial based and underwater by divers, ROVs and autonomous vehicles.

We have proved this in a real life scenario and we are very pleased with the outcome and the use and support Sketchfab has given us. Thank you very much.

One last thing, the police did ask me not to find anything else on the beach as the paperwork for this type of thing is fairly in depth. So what next can we find and model… time will tell!

That’s quite a story Chris! Thanks for sharing.

You can see more 3D scans by Leak Heat on their Sketchfab profile, and visit their company site on www.leakheat.com/.