For me, a positioning system has a few requirements to be appropriate for widespread use in Rainbow’s End-style augmented reality:
The system should scale to any number of mobile devices.
The system should work indoors and outdoors. It should also work underground in places like subway stations.
No one should be able to track the position of devices in the system.
A mobile device should require minimal warm-up time of less than ten seconds
A mobile device should be able to determine its position on an ongoing basis with a frequency of at least 30Hz.
A mobile device should be able to pinpoint its position down to 1cm or less.
A mobile device should be able to operate with its positioning system activate at all times and still maintain a reasonable battery life.
The closest current contender is GPS. Let’s see how it does on each of those front:
So far so good. The GPS satellites don’t care how many receivers there are. GPS has weathered an explosion in the number of receivers over the past ten years and come through just fine.
GPS fails this one. It works outdoors most of the time but indoors only if you are near an equator-facing window. It never works underground.
Since GPS receivers only listen, this is generally true. The 911-driven remote activation requirements allow some GPS devices to be trackable, but the tracking happens through the phone’s network connection not through the positioning system itself.
GPS manufacturers claim warm-start times under ten seconds. According TTFF measurements for many models from 2003 some models can warm-start in under ten seconds. Things have significantly improved since then.
GPS receivers typically send an NMEA position sentence once per second (or 1Hz). SparkFun lists a few GPS components in the 5-10Hz range. It’s not clear if this is a limitation of the system or if GPS has an inherent update frequency limitation, so we’ll assume that improved chipsets will get the frequency up to 30Hz.
GPS completely fails this one. Under ideal circumstances and non-real-time post-processing GPS will get you down to about 2cm. Under normal circumstances the accuracy is more like 10-50m. GPS will tell you what street you’re on (if you assume you’re on a street) or what house you’re in, but it can’t tell you what room you’re in.
Current GPS receivers still draw too much power to leave them on all the time, but Moore’s Law is changing that. They should be always-on in a few more years.
GPS fails in two very important requirements: where you can use it and how accurate it is. Satellite-based replacements for GPS are likely to have the same failure indoors and underground. If it ever launches, Galileo is supposed to have a commercial encrypted system that provides accuracy down to 1cm, but it still won’t work indoors or underground. Relying on satellite-based positioning is a dead-end for augmented reality.
The other way that AR researchers are tracking position is with a camera-based system. No one has yet built such a system that operates out in the wild, but it would be theoretically possible. A visual tracking system would operate by comparing the stream of images from the camera against a database of images that is stored in the cloud. The exact form of that comparison is a matter of much research. Whether the comparison happens in the cloud or on the mobile device is also an open question. The general form of the system (large database in the cloud and a stream of images from the camera on the mobile device) is pretty stable though. One key assumption here is that the image database for a city-sized area is far too large to download to the mobile device. Let’s see how that does on our requirements:
Because of the requirement that we either stream the camera images to the cloud or the local portion of the database from the cloud to the mobile device, each additional user puts incremental load on the system. The number of users in a local area will be limited by the mobile network bandwidth available to those users. The number of total users of the system will also be limited by the server capacity of the system’s provider, but that end of things can scale out more easily.
This system would work anywhere the database covered. Indoor and underground environments would be fine. Areas where the camera could only see other people (i.e. crowds) would be a problem because the database wouldn’t have anything static to compare against. If the camera depends on environmental light this system would perform poorly in dark areas (or at night.)
If the camera’s images are streamed to the cloud the system’s provider would know exactly where each device was at all times. If the portion of the database related to a small area is streamed down to the device then the service provider will only be able to locate the device to within that small area. Either way, the provider will know where the user is to within a few hundred feet.
If the camera images are streamed to the cloud, start-up times should be more or less instant. If the database is streamed down to the device it may take a few seconds to get things started, which is well within our tolerance.
Current visual tracking systems have trouble reaching 30Hz, but Moore’s Law should take care of that eventually. For a system that streams the video to the cloud bandwidth can also affect update frequency. Once the link starts filling up with streams from other devices the update frequency goes down for every device.
Visual tracking systems are quite accurate. Finding hard numbers is difficult, but there’s no reason to believe that a visual tracking system would be less accurate than 1cm.
Visual tracking systems are power-hungry at the moment. They require fast cameras, fast network connections, fast CPUs on the mobile devices, and lots of memory. Because so much of the system is unknown, it’s hard to pin down numbers, but I would estimate that we need 100x power reduction before leaving this system on all the time is realistic. That will take Moore’s Law about ten years to accomplish.
If we can solve the low-light and power issues, a visual tracking system would certainly work for a small number of users. Solving the bandwidth constraint for a system that much of the population is using is a more daunting issue. All that bandwidth also makes the system expensive to operate, which will be passed on to end users as either usage fees or advertising. Building a workable generally available visual tracking system not an impossible problem, but it’s certainly a difficult one.
Personally, I’m not satisfied with either of these systems. I have thoughts on how to build a better one, but I’ll save those for a future post. What do you think? Am I missing any major requirements? Are any of mine unnecessary? Am I representing GPS or the imagined visual tracking system unfairly? Let me know in the comments!
In the interest of seeing just how wrong I can be twelve months from now, here is a list of things I think will happen in 2011. This is possibly the worst day of the year to write such a post, what with CES starting on Thursday, but that’s never stopped me before.
Netflix will continue to kick ass. Their selection of streaming movies and TV shows will explode in 2011, though they will have to pay more for all that content.
My internet connection will improve. Self-fulfilling prophecy? I hope so! I’ve had 1.5Mb/768kb DSL for ten years. It’s well past time to upgrade. In theory Qwest will be putting 20Mb service into my neighborhood soon, so maybe that’s in my future.
Android will continue to kick ass and take names. 2011 will see >60% smartphone market share, a dizzying array of tablets and phones, and probably even some netbooks by fall. More and more apps will start to ship on both Android and iOS at the same time.
Android 3.0 will include improvements for the annoying OS upgrade delays on that platform. Google will come up with some way to apply pressure on handset manufacturers and carriers to deliver the latest version of Android to uses in a more timely fashion.
Still no consumer-level visual pass-through AR glasses. I said it last year, and I’ll keep saying it every year until I’m wrong.
This will be the year the electric car revolution began. The Nissan Leaf and Chevy Volt will both sell well and set the stage for the electric cars of 2012 (including the Tesla Model S) to blow the doors off.
This year will feature one “unthinkable ten years ago” level medical advance. Will it be a cure for cancer? Regrowing limbs from your own stem cells? Repair of severed spinal cords? Pain medication with no side effects? Who knows, but something big is going to happen this year.
And that’s it! If it’s not on this list it’s not going to happen in 2011!
(Think maybe something might happen in 2011 that wasn’t on this list? Please add your own prediction in the comments and we’ll see how you do!)
I realize these “predictions at new years” posts are a little cheesy and that you see them everywhere. I enjoy writing them, so I’m going to do it anyway. This is my look back at my predictions of one year ago to see how I did.
Correct. It is arguably fair to call STO the only significant MMO launch of 2010. APB sort of fizzled, after all. I haven’t heard much about STO since its launch though… not sure how it’s actually doing.
Sort of Correct. I could only come up with two cancellations from my list:
APB was actually cancelled after it came out. That’s the wrong way around.
The Agency is rumored to be more or less shut down at this point. Nothings been announced here and probably never will be.
Correct. Reports are that they’ve both sold millions of units. Natal (now named Kinect) has also incited thousands a cool Kinect Hack YouTube videos. Dance Central is pretty cool, so at least one great Kinect game is already out.
Correct. According to this chart the unemployment rate in the US peaked at 10.6% in January 2010.
Wrong. I’ve seen no evidence that Junaio, Layar, or Wikitude are ready to stray from their AR roots yet. In fact they seem to be doubling down by making the set of things they can position at a GPS location much more complete.
Correct. There haven’t been any interesting new products in the area of wearable displays. Lots of talk at ARE2010 and elsewhere, but nothing concrete yet.
Correct. Google Goggles came to the iPhone, but other than that neither company has done anything on the AR front.
Wrong. There’s no indication that the marketing world (or consumers) are tired of simple AR campaigns. If anything the campaigns are continuing to grow in popularity and complexity.
Correct. The iPad and iPhone 4 came out. Good thing I didn’t predict how well the iPad would do… I would have massively underestimated it.
Sort of wrong. Technically 200,000 is more than 50,000, but I completely underestimated the meteoric rise of Android during 2010. I thought that Android phones would only outsell iPhones until iPhone 4 came out, but they topped the iPhone in May (in the US) and never looked back.
Wrong. Wave doesn’t inter-operate with anything. That’s a bit part of why it failed in my opinion.
My score was 9 correct and 4 wrong. Better numbers than last year, but I think I made more safe bets for 2010 too. 2010 went pretty much how I expected it would (with the notable exception of Android going gangbusters.)
How was your year? Did anything surprising happen?
Another in my ongoing series of ideas I’ll probably never act on. Do whatever you like with this. If you actually make the game and it runs on Android, let me know. I’d love to try it out.
The High Concept
Play through a role-playing game adventure on your mobile phone while moving around your local park, hiking through the woods, or wandering the streets of your home town. Participate in simple quests solo, or play with friends. Or if you prefer, develop your own adventures and share them online for other people to play.
The Inspiration
In the 1980s and 90s there were a series of books called Fighting Fantasy that let players play through an RPG-like adventure without a gamemaster. Combine a mobile implementation of those books with geocaching and then let the users create all the actual content and you have GPS Quest.
The Technology
Building GPS Quest would be straightforward:
Develop a simple RPG engine with monsters, loot, stats, and leveling up. Leave as many hooks as possible for user-generated content to modify things. Combat will probably want to be turn-based. Write a mobile app to resolve combats in the system. This is by far the hardest step. Probably do this with just one player for the first version.
Build a back end that can track a player’s RPG stats over time. Include a quest system that can unroll an adventure in front of the player as they move around the world. This would probably be waypoint-based so the user can look at the next place to go on a map on their phone.
Build quest creation tools that let a user (you) write new quests in the actual physical world.
Publish all this to the world.
Iterate until massively popular
There are many hundreds of features that could be added once the basic system is up and running. Some ideas include:
Multiplayer. First for small parties of 2-5 people and them maybe for raids of 20-40 people.
Audio for monsters, navigation, and quests. You could download it all before starting the quest so it could play quickly.
Custom art for quests. Might want to download this ahead of time too.
A builder-maintained bestiary
A builder-maintained loot catalog
Tools to remap existing quests onto new locations
Matchmaking tools to help players find each other
The sci-fi, zombie, pirate, superhero, spy, vampire, giant robot, caveman, and not-at-all-fantasy-medieval versions of the same game. That last one is so some SCA people can feel comfortable playing your game.
Leaderboards for quest builders, quest remappers, and players to give all of those people bragging rights.
More simple geocaching features like buried treasure and traps that players can leave for each other.
Ports to whichever platform you didn’t launch for in the first place.
Trading systems, auction systems, crafting systems
This is my talk from last Wednesday’s Seattle Augmented Reality Meetup. I will upload the discussion that followed as a separate video later today. Comments and feedback are welcome… just comment below or over on Vimeo.