Autonomous headlamp design

[Floyd]

Hi all,

I am an electrical engineering student currently undertaking a third year design course. The project I am designing is an autonomous caving/mining headlight, detecting the environment’s ambient light to accordingly adjust the output light intensity and frequency. This will allow for hands-free operation, with the goals of saving power, increasing safety and convenience, as well as a more accurate colour reproduction of the dark environment. Some of the other features considered are the control characteristics of the light, type of light, weight distribution of the circuitry and a disable function to allow manual control of the light

I found a similar product ‘Petzl Nao’, unfortunately only after my design proposal was accepted. Their product measures the reflective light of its own beam which gives a small sensing angle and disregards light from the surroundings (e.g. from other cavers). Also there product comes with a $200 price tag (my market research on this product has everyone saying the price tag is its major flaw) for a max 355 Lumens. If the use of LDR's proves to be sensitive enough, I believe mine would be much more cost effective.

Also talking to a caving instructor in New Zealand, he said that he took a flame into a cave once and gave a realistic 3D feel to the environment. That's why I have a manual colour adjustment for the user.
Has anyone ever used a colour other than white light that gave a much more realistic visual of the environment?
At this stage I am trying to gather as much information as I can for the design. So far I am planning to use ~3 CREE XM-L/2 LEDs (possibly with multicolour LEDs), and simple optics with basic LDRs for light sensing. For the batteries, I will probably use 18650s or AAs, and a microcontroller to handle the logic of the dimming and colour variation. I am wondering if these are good choices; any feedback or ideas would be of great assistance.

Cheers,
Floyd