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Theoretical reflection| My Visual system

How I build my own cockpit ?

Visual system.

On of the most important parts of a good simulator is a good visual system. About 80% of the movement is created by a correct image building. Because this part is one of the two most expensive parts of the whole cockpit project, it has taken me a long time before I decided what system I would finally choose.
First some review. From the start of the project I always played with the thought on constructing a collimator with two monitors.
What is a collimator I hear you say.

It is a system that can create a view in depth (Virtual 3D). This is made by an image that is projected on a hollow mirror and can by seen through a beam splitter. The image is generated by a 24' inch monitor with high light intensity. The beam splitter is a glass that is covered on side with a mirrorcoating and can be seen through from the other side. The image comes on to a hollow mirror from glass. You need to be in the exact focal distance to view the image in depth.

collimator

 

 

 

 

 

 

 

 

 

This complete project never saw the light because it is to hard to create and the monitors were very hard to find. Above all it is unaffordable. The second disadvantage is the brightness. First of all you need to have monitors with a very high light intensity because you loose a lot of light through the beam splitter. It is only a very good solution when you only want to do night flights. The third disadvantage is that you always need to be in exact focal distance to see the image well. The fourth disadvantage is the weight, can you imagine how match a glass mirror of 100cm by 60cm would weigh and add to this the weight of a 24' inch monitor, than 150kg to 200 kg is not far away. If you then know you need two of them, one for each side than it is out of the question. So goodbye collimator.

bendscreen

 

 

 

 

 

 

The second idea was to make a round screen with the focal distance right in the center of the view position, this would again create a 3D effect. To build the screen in itself could be overcome. But to project the image would need a special projector with adapted program only costing a little € 25.000 to € 35.000. A very little bit over my budget. So this idea was very quickly berried.

So only one solution was left over. A flat screen and a overhead projector.
After looking around a bit my eye fell on a XGA projector with a great angle and had 2000 ansi lumen. It would be possible to create an image of 2m on 1.6m  from a distance of 2.5m

projector

 

 

 

 

To position the projector we made a special suspension system to be able to put the projector up site down. We also build a screen. This is made of MDF plate of 8mm and is glued to a wooden framework.

screen1 screen2 screen3

 

 

 

 

This all is than painted with mat white latex paint and around the edges with mat black paint. So the reflection on the screen is next to nothing. All the surrounding walls where the cockpit is positioned are also painted in black latex paint, so there isn't any reference point outside the cockpit. On one side witch is still open we placed a black curtain. Now the cockpit is completely sealed of from the outside world. This makes that you have no idea how the cockpit is orientated and this creates the illusion of motion. It is like sitting in a train at a station, when the train next to you starts running you have no idea if you are moving or if the train next to you is moving. All this because you don't have any fixed reference point.

view1 view2

I can assure you when I now take a turn you really have the impression you are in a turn and your body is moving along with it. If you would be standing in the door without holding yourself you even would fall down.

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© Verley Jan 2007-2017 original text from 2004 translation Jan Verley