Digital Twins and Unreal Engine

I’ve had a ton of experience with Unity and Digital Twins but I have been paying attention to Unreal Engine. I think the open nature of Unity is probably more suited for the current Digital Twin market, but competition is so important for innovation. This project where Unreal Engine was used to create a digital clone of Adelaide is striking but the article just leaves me wanting for so much more.

A huge city environment results in a hefty 3D model. Having strategies in place to ease the load on your workstation is essential. “Twinmotion does not currently support dynamic loading of the level of detail, so in the case of Adelaide, we used high-resolution 3D model tiles over the CBD and merged them together,” says Marre. “We then merged a ring of low-resolution tiles around the CBD and used the lower level of detail tiles the further away we are from the CBD.”

Well, that’s how we did it at Cityzenith. Tiles are the only way to have the detail one needs in these 3D worlds and one that geospatial practitioners are very used to dealing with their slippy maps. The eye-candy that one sees in that Adelaide project is amazing. Of course, scaling one city out is hard enough but doing so across a country or the globe is another. Still, this is an amazing start.

Seeing Epic take Twinmotion and scale it out this way is very exciting because as you can see from that video above, it really does look photorealistic.

But this gets at the core of where Digital Twins have failed. It is so very easy to do the above, crate an amazing looking model of a city, and drape imagery across it. It is a very different beast to actually create a Digital Twin where these buildings are not only linked up to external IoT devices and services but they should import BIM models and generalize as needed. They do so some rudimentary analysis of shadows which is somewhat interesting, but this kind of stuff is so easy to do and there are so many tools to do it that all this effort to create a photorealistic city seems wasted.

I think users would trade photorealistic cities for detailed IoT services integration but I will watch Aerometrex continue to develop this out. Digital Twins are still stuck in sharing videos on Vimeo and YouTube, trying to create some amazing realistic city when all people want is visualization and analysis of IoT data. That said, Aerometrex has done an amazing job building this view.


Moving Towards a Digital Twin Ecosystem

Smart Cities really start to become valuable when they integrate with Digital Twins. Smart Cities do really well with transportation networks and adjusting when things happen. Take, for example, construction on an important Interstate highway that connects the city core with the suburbs causes backups and a smart city can adjust traffic lights, rail, and other modes of transportation to help adjudicate the problems. This works really well because the transportation system talk to each other and decisions can be made to refocus commutes toward other modes of transportation or other routes. But unfortunately, Digital Twins don’t do a great job talking to Smart Cities.

Photo by Victor Garcia on Unsplash

A few months ago I talked about Digital Twins and messaging. The idea that:

Digital twins require connectivity to work. A digital twin without messaging is just a hollow shell, it might as well be a PDF or a JPG. But connecting all the infrastructure of the real world up to a digital twin replicates the real world in a virtual environment. Networks collect data and store it in databases all over the place, sometimes these are SQL-based such as Postgres or Oracle, and other times they are simple as SQLite or flat-file text files. But data should be treated as messages back and forth between clients.

This was in the context of a Digital Twin talking to services that might not be hardware-based, but the idea stands up for how and why a Digital Twin should be messaging the Smart City at large. Whatever benefits a Digital Twin gains from an ecosystem that collects and analyzes data for decision-making those benefits become multiplied when those systems connect to other Digital Twins. But think outside a group of Digital Twins and the benefit of the Smart City when all these buildings are talking to each other and the city to make better decisions about energy use, transportation, and other shared infrastructure across the city or even the region (where multiple Smart Cities talk to each other).

When all these buildings talk to each other, they can help a city plan, grow and evolve into a clean city.

What we don’t have is a common data environment (CDE) that cities can use. We have seen data sharing on a small scale in developments but not on a city-wide or regional scale. To do this we need to agree on model standards that allow not only Digital Twins to talk to each other (Something open like Bentley’s iTwin.js) and share ontologies. Then we need that Smart City CDE where data is shared, stored, and analyzed at a large scale.

One great outcome of this CDE is all this data can be combined with City ordinances to give tools like Delve from Sidewalk Labs even more data to create their generative design options. Buildings are not a bubble in a city and their impacts on the city extend out beyond the boundaries of the parcel they are built on. That’s what so exciting about this opportunity, manage assets in a Digital Twin on a micro-scale, but share generalized data about those decisions to the city at large which then can share them with other Digital Twins.

Graphic showing chart of change over time

And lastly, individual Smart Cities aren’t bubbles either. They have huge impacts on the region or even the country that they are in. If we can figure out how to create a national CDE, one that covers a country as diverse as the United States, we can have something that can even benefit the world at large. Clean cities are the future and thinking about them on a small scale will only result in the gentrification of affluent areas and leave less well areas behind. I don’t want my children to grow up in a world like that and we have the processes in place to ensure that they have a better place than use to grow up in.


Apple’s Digital Twin is All About Augmented Reality

Now before we get too far, Apple has not created anything close to a Digital Twin as we know them. But what they have done is created an easy way to import your building models into Apple Maps. Apple calls this their Indoor Maps program.

Easily create detailed maps of your indoor spaces and let visitors see where they are right in your app. Organizations with large public and private spaces like airports, shopping centers, arenas, hospitals, universities, and private office buildings can register for the Indoor Maps Program. Indoor maps are built using industry standard tools and require only your existing Wi-Fi network to enable GPS-level location accuracy so visitors can navigate your spaces with ease.

Victoria Airport in the Apple IMDF Sandbox

OK, so clearly this is all about navigation. How do I know where I am in a building and how do I get to a place I need to be. Of course, this is somewhat interesting on your iPhone or iPad in Apple Maps, but clearly, there is more to this than just how do I find the restroom on floor 10 of the bank tower.

To load your buildings in Apple you need to use Mapkit or Mapkit.js and convert your buildings into Indoor Mapping Data Format (IMDF). IMDF is actually a great choice because it is GeoJSON and working toward being an OGC standard (for whatever that is worth these days). I did find it interesting that Apple highlights the following as the use case for IMDF:

  • Indoor wayfinding
  • Indoor routing
  • Temporal constraints
  • Connectivity amongst mapped objects
  • Location-based services
  • Query and find by location functionality

If you’re familiar with GeoJSON, IMDF will look logical to you:

  "id": "11111111-1111-1111-1111-111111111111",
  "type": "Feature",
  "feature_type": "building",
  "geometry": null,
  "properties": {
    "category": "parking",
    "restriction": "employeesonly",
    "name": {
      "en": "Parking Garage 1"
    "alt_name": null,
    "display_point": {
      "type": "Point",
      "coordinates": [1.0, 2.0]
    "address_id": "2222222-2222-2222-2222-222222222222"

I encourage you to review the IMDF docs to learn more but we’re talking JSON here so it’s exactly how you’d expect it to work.

Because IMDF buildings are generalized representations of the real-world data, this isn’t actually a Digital Twin. It also means that you need to do some things to your files before converting them to IMDF. Autodesk, Esri, and Safe Software all support IMDF so you should be able to use their tools to handle the conversions. I’ve done the conversion with Safe FME and it works very well and probably the best way to handle this. In fact, Safe has an IMDF validator which does come in handy for sure.

Safe FME support of IMDF

What does make moving your buildings to Apple’s Indoor platform is the new iPhone 12 and iPad Pro LiDAR support. This brings out some really great AR capabilities that become enabled with Apple’s devices. As I said last week, the LiDAR support in the current devices is more about getting experience with LiDAR use cases than actual LiDAR use. This is all about eventual Apple Glass (and Google Glass too) support and the AR navigation that can be done when you have hyper-accurate indoor models in your mapping software.

I’ve been dusting off my MapKit skills because I think not only is this capability useful for many companies but it really isn’t that hard to enable. I am spending some time thinking about how to use the extension capability of IMDF to see how IoT and other services can be brought in. Given the generalized nature of IMDF, it could be a great way to allow visualizing IoT and other services without the features of a building getting in the way. Stay tuned!


COVID-19 is Showing How Smart Cities Protect Citizens

I feel like there is a before COVID and an after COVID with citizens’ feelings for Smart City technology. Now there is an election tomorrow in the United States that will probably dictate how this all moves forward and after 2016, I’ve learned to not predict anything when it comes to the current president. But, outside that huge elephant in the background, Smart City concepts have been thrust into the spotlight.

Photo by Michael Walter on Unsplash

Most cities have sent their non-essential workers home, so IoT and other feeds to their work dashboards have become critical to their success. The data collection and analysis of the pulse of a city is now so important that traditional field collection tools have become outdated.

Even how cities engage with their citizens has changed. Before COVID, here in Scottsdale, you needed to head to a library to get a library card in person. But since COVID restrictions, the city has allowed library card applications in person which is a huge change. The core structure of city digital infrastructure has to change to manage this new need. Not only engaging citizens deeper with technology but need to ensure those who don’t have access to the internet or even a computer are represented. I’ve seen much better smartphone access on websites over the summer and this will continue.

Even moving from a public space to a digital space for city council meetings has implications. The physicality of citizens before their elected leaders is a check on their power, but being a small zoom box in a monitor of zoom boxes puts citizens in a corner. Much will have to be developed to have a way for those who don’t wish to be in person be represented as well as those who choose to attend meetings in person.

COVID has also broken down barriers to sharing data. The imagined dashboard where Police, Fire, Parks & Rec, City Council, and other stakeholders have come to fruition. The single pane of glass where decision-makers can get together to run the city remotely is only going to improve now that the value has been shown.

Lastly, ignoring the possible election tomorrow, contact tracing, and other methods of monitoring citizens as they go around the city has changed mostly how people feel. Before COVID, the idea that a city could track them even anonymously scared the daylights out of people. But today we are starting to see the value in anonymous tracking so that not only we see who has been in contact with each other but how they interact in a city with social distancing restrictions.

Future planning of cities is changing and accelerated because of COVID. The outcome of this pandemic will result in cities that are more resilient, better managed, planned for social distancing, and are working toward carbon neutral environments. In the despair of this unprecedented pandemic, we see humanity coming together to create a better future for our cities and our planet.