Originally Posted by elkaholic
I have heard rumors of someone coming out with a rangefinder that compensates for all the environmental things that we deal with. Anybody else heard this and if so, who is making it and what all does it compensate for? Oh ya! Wonder what it costs!!..Rich
I haven't seen any new ones. There are rangefinders which compensate for elevation and can compute ballistic drop. However, the real problem is that windage needs to be addressed too. I have not seen a commercial rangefinder which does that.
To be "smart" enough to be useful it would need to be able to be given the bullet BC and muzzle velocity and the distance the rifle is zeroed at as user input. It would then need to measure:
1. Distance to the target. (like any laser rangefinder)
2. the crosswind velocity. An ultrasonic anemometer can be compact, rugged, and cheap with adequate resolution. It can only measure wind at the shooters location which isn't perfect but better than nothing.
3. Angle of inclination to the target. A sensor and 1 IC to read it.
4. Air temperature (one integrated circuit (IC))
5. Absolute barometric pressure. (one IC).
None of those devices requires new technology or much R&D. Most of the effort woiuld be packaging and integrating the software.
From air temperature and absolute barometric pressure it can calculate air density and speed of sound and with the other information it could determine the bullet trajectory. With that it can display the number of moa or mils for hold over windage or clicks to adjust target knobs. Adding barrel twist information as an input would allow calculating spin drift and included in the output added to windage as needed.
It should be little larger or heaver than a "standard" laser rangefinder.
An advanced model could put it all of that inside a riflescope. Then add a scintillation anemometer to measure crosswind velocity over the entire trajectory (an extra sensor and software but using the rangefinder's laser), add a rate gyro (one IC) so that as you track a moving target the correct lead is added, add a liquid crystal reticle which is automatically adjusted in real time which eliminates the knobs on the scope. An LCD as found in many decent SLR cameras would do. Add a gps receiver and a flux gate compass and it can automatically calculate c\Coriolis effect as well as providing a full gps map and navigation tool. It's only a couple more ICs. Those additions would need some R&D for hardware and software but no technology breakthroughs.
An image intensifier could make it usable on moonless nights as an expensive option.
Cost? I don't have a clue. The first units would be pretty high but probably less than trying to do it all with individual instruments as only one processor and display would be needed. Manufactureers have to exoect to recover their R&D costs or it won't even get worked on.. If the military pays for the R&D it probably would not be unreasonably expensive perhaps no more than a "top of the line" optical scope $(2000?) In a couple of years after the public becomes aware of them you should be able to get the NcStar knockoff on Ebay for under $500. There really isn't a lot to a unit which could do all that but to get the cost down a company would need to sel many f thousands like they do with cellphone and ccd cameras. . I doubt there's a big enough market.
About 5 years ago I saw mention of a DARPA "request for proposal" for military sniping scopes with similar "suggestions" for features in one of the laser trade magazines. I don't know if anything came of it. The results would no doubt be classified.
Over ten years ago I saw an Israeli article on using an experimental scintillation anemometer for sniping. It used a low power laser, a PC, and two photo sensors with optics which looked similar to a set of binoculars. It should not add much cost to a rangefinder which already provides a suitable laser. The article said the experimental unit was about as good at predicting wind deflection as their expert snipers using visual estimates from "mirage." at ranges to a kilometer. It basically was using the same method of detecting the movement of windblown sun warmed air cells but using sensors and computations faster and higher resolution than a human's ability. I've seen nothing about it since,
Abrams tanks use a form of laser anemometer with longer range and (i believe) three axis capability. A web search will show mention of it though little in the way of details. I suspect it works off scattered laser light from airborne particles resolving both lateral movement and Doppler velocity vs distance, but I could be wrong. I'm just guessing from sketchy information.