In the coming weeks I will examine a few technologies that could function like a holodeck but first I’ll examine how far we are today.
Lets start with the basics here: What is a holodeck? The concept of the holodeck originates from Star Trek The Next Generation. It is a large room in which reality can be simulated. It is a room which uses a combination of holographic images, teleportation technology, replication technology, tractor beams and force fields to create a lifelike representation of the world (whichever world that might be). The holodeck as described in Star Trek is fiction of course and quite possibly will never be a reality as described. There are however several technologies that will or could basically do the same thing.
First off the personal computer and gaming systems. You might think it is a big step from these to a holodeck but actually a lot of things needed for a holodeck are actually already incorporated in these systems. They render their virtual worlds in 3D, contain information about what are solid objects, how you move over certain terrain, great gaming features and more. Of course a solid object is just solid so a wall and a person will both feel like solid brick but still many information in games is usable for a holodeck. of course the biggest issue is that you cannot enter the world yourself. You will always need to rely on a screen and some kind of input device. (although the Wii, Xbox kinect and Playstation Eye take a few first steps towards eliminating the clumsy (unnatural) controller altogether. On the plus side these systems are cheap and have come a long way in just a few decades.
A step up is a system called the CAVE. It has three or more walls (sometimes including floor and ceiling) on which 3D images are projected. With 3D glasses (similar to the ones for your 3D tv) you get a holographic simulation. By walking around an object you can view it from all sides like an actual holographic image. With new technologies (similar to the aforementioned Xbox Kninect etc.) you are even able to interact with these objects to some degree. The lack of a physical form is a big disadvantage however. To be able to truly interact with an object you need to be able to handle it as well. That is why most video’s of people interacting with virtual objects seems so clumsy, you just cannot get an idea of weight, form and feel of an object. Another big disadvantage of this system is the space you need (it is a room within a room so you need an awful amount of space) and the money a system like this costs.
The last problem is that it is unfit for young children and some people experience headaches when using the system. This is due to the actual technology. The information our eyes gets says an object is somewhere in the room, the actual object is on a screen however and so the eyes shift focus between the screen and where the object is expected to be. This rapid focussing between the two causes the headaches but is also why children shouldn’t use it. Their eyes are still developing and the 3D technology can hurt the development of the eyes.
The best holodeck equivalent we currently have are the big simulators used to train pilots, ship captains, Formula One drivers or are used in an amusement park as entertainment. They act and feel like the actual thing and by the use of hydraulic pistons simulate movement of the ship, car or plane. The latest version, based in the Netherlands, is even able to simulate gravity (or the lack thereof). The biggest disadvantages of these machines is that they are very large, require a crew to operate (both for maintenance and running the training), cost a lot of money and require you to purchase a new machine every time you want to use it for a different plane/car/boat.