Lighting Simulation: Dive into a Submarine Control Room!

Lighting plays a significant role in the operating rooms of submarines: discover how simulation optimizes the working conditions in this darkened rooms!

October 8th, 2017 | Innovation

Submarine 2

Light: a crucial element of the submarine control room

As the tactical center of a submarine, operations rooms must always provide optimal working conditions to guarantee the safety and efficiency of operations and decisions. Lighting plays a significant role in these operating conditions: sight is critical when it comes to making military decisions. Indeed, lighting is a key factor for submarine operations rooms for several reasons, and each lighting configuration on the boat is essential. 

Normal operating conditions

Under normal operations, the submarine control room is fully lit with white LED or fluorescent lighting. This lighting facilitates movement, alertness, awareness, and maximizes the readiness of the crew on a prolonged basis. This configuration is the preferred one regarding lighting and is the default one when on the surface during the daytime, and the mandatory one when in port and when submerged

Intermediate night vision conditions

Ships often change lighting during "darken ship" or after sunset and after sunrise. At that moment, the lighting dims and switched to red and /or blue lights.

  •  Red lighting helps preserve night vision. Red allows for quicker night vision acclimation, according to the Purkinje effect[1].
  •  Blue light helps reduce glare on screens and eye strain. Operations rooms usually use a blue light to facilitate easier viewing of monitors and displays, charts, and general reading. Charts and writing which are not designed for red light can be hidden or obscured in red light.

Currently, blue lights are preferred to red lights for practical reasons. Actually, the lights stay the same in the operations room most of the time, while underway, and it is blue. The switch from white/red lights mainly serves 2 purposes. They help make transitions from inside to outside easier on the eyes. Having lights dim at night also helps with keeping a night and day rhythm for people in the submarine, who never see the sun, sometimes for weeks. It enables the body to easily adapting back to the dai schedule.

This intermediate stage also allows some time for the crewmember's eyesight to adjust to lowered light levels before turning everything black: if we just went from white to black, nobody would be able to see anything for at least a few minutes, which is extremely dangerous.

Fully dark conditions

On a submarine, adjusting the light can help whoever is operating the periscope. The submarine needs to rig for black when at periscope depth. Why is this important? The safety of the entire ship depends on the periscope operator and on the optimal viewing conditions. Periscopes use a series of mirrors to peer outside, and any light could prevent the operator from correctly seeing what is going on outside. As the open ocean at night is exceptionally dark, the darkness needs to be absolutely complete on the ship. To bypass this, most of the newest submarines use photonics masts instead of periscopes. This avoids the need to rig for black in the operations room. This system uses high-quality cameras, tv monitors, and joysticks, and entirely replaces the periscope watch.

Now, let’s study into details how this various lighting conditions can be recreated, simulated and optimized thanks to optical simulation means.

 

Simulation: the best way to optimize the safety of operations in any conditions

Everything starts with a geometric model created using mechanical CAD software... As we’ve explained in the previous section, lighting inside a submarine and especially in a control room is of high importance for safety.

 

To show how OPTIS’ physics-based optical simulation can help predict if the lit environment the capabilities of OPTIS physics-based lighting simulation tools, we have modeled a simplified operations room of a submarine.

 

Hop aboard and learn everything about the lighting simulation of a submarine operations room!

 

 

The first thing is to place and set light sources as well as define the materials of the various mechanical surfaces included in the model. We can then proceed to a series of simulations, that will allow us to determine the homogeneity of the illumination of the global scene in 3D. On the above pictures, we have positioned a single light source, to increase the contrasts on the final result.

As shown above, the calculation results can be presented either in false colors and also in gray level: the latter representation being more realistic as to the perception that we will obtain in the end.

Note here the phenomena of shadow and reflections, especially on the ground, near the control desks.

 

 

 

Let’s have a closer look at one of the control desks, to determine the levels of illumination and in-homogeneity on the station. The desk here is simplified, but in reality, it is very complex and includes many commands and buttons, as well as indicator lights, displays and of course is manipulated by one or more operators. The viewpoint can also be modified in the 3D environment to observe other directions likely to hinder the submariners. Here above, let’s switch to gray level to observe this environment better.

 

The result can be seen directly in a real-time 3D virtual reality environment, where the observer is tracked and explores the area.

 

The result on the left is a luminance calculation of the reflections observed on one of the control screens. The screen is positioned on the desk, and it is crucial to superimpose a real signal that will be displayed to evaluate the potential reflection disturbances that could be generated by the different light sources within the control room. Luminance levels and colors are also available for this result.

 

Here is the same gray level result, to give you a better understanding of the shape of this reflection. What you can see at the bottom of the screen is the keyboard.

 

 

Finally, let’s see how a complete environment would look like. We add several additional luminaires. This way, you can observe the improved homogeneity of the lighting along the control desks, as well as the reflections due to the screens positioned on the desk.

 

Some unwanted brightness can be seen here: lighting design tools will allow you to optimize and reduce these effects.

 

 

 

Our tools can also provide true color images, based on real physical models, to highlight not only the in-homogeneities lighting but especially the discomfort due to reflections and visibility of direct light sources.

It is on this basis that we apply our tools to larger geometric models provided with shadow and reflective details.

 

Thanks to our human eye model, OPTIS solution provides the way submariners will perceive in this low light level environment

 

Virtualizing the submarine  for design, engineering and maintenance purposes

Light remains at the heart of many industries’ concerns and this goes for the military submarine one. If the simulation is the best way to make sure that submarines will have efficient lighting, ensuring a high safety within the darkness of the see, virtual prototyping offers many other possibilities.

 

Real-time configurations offered by THEIA-RT allows the exploration of a future product, in real time, considering geographic location, time of day and weather conditions, to offer an accurate preview of a product's appearance in a given environment. The VR experience lets you visit your product from the inside with a real-time rendering and interactions. On another hand, constructions such as submarines always need to be in a perfect state to ensure the quality and safety. That is why heavy checking is performed before any launching. Teams need to verify the way it will be assembled, used, maintained and disassembled throughout time. But the maintenance of such a way of transportation is not easy and requires time and precision. The training of those in charge of this maintenance is also very time-needy. HIM can simulate real interactions to train your operators and avoid any potentially hazardous or problematic situation. Here you can say that the future of submarines design relies on virtual reality! 

 

[1] https://prateekvjoshi.com/2013/08/21/purkinje-effect/