Most accurate positioning system

Ill come strait, I am new to this hobby, I have mostly no idea what I am doing, but for a specific project that I have in mind I need some questions sorted before I start.
Even if I don’t get my answer ill still work on quadcopters and such, but not for this specific project.

So in short, the quad copter will follow a path specified and it will follow it close to the ground (5 ft or lower) with under 1 inch accuracy, so a very accurate positioning system

Specifications:
*Under 1 inch in accuracy.
*Cover a distance of 150ft x 150 ft would be nice, or at least 90ft x 90 ft,
*relatively cheap/affordable, not too crazy.
*On site beacons are allowed, it does not have to be fully mobile such as a GPS or bluetooth
*Site is a flat surface, no hills/tree/etc

Any ideas?

Lidar-lite states a 1cm accuracy up to 40m. You will need to set up code that can fully exploit that resolution though I think. At under 2m height that resolution should be simple though.

Following other beacons will take some extended programming but nothing in your mission sounds particularly challenging otherwise.When you say ‘cover’ an area, what do you mean, overfly it in a pattern?

Yes overfly is the term that best describes it, so lets say I want it to follow a 10ft or 90ft circle pattern starting from point a. And it must hover within 5 feet from the ground (or 1.5 meters) and be within 1 inch accurate.

Point A may also have a beacon like I said, or it can be calibrated to that spot but like you said this requires some coding which I want to learn,
(And another reason for this project is the learning experience)

But with my recent research I am far interested in a RTK GPS systems such as this
store.swiftnav.com/s.nl/it.A/id.4216/.f
Or a kick starter for half the price, which is a kick starter but show some promising results.
indiegogo.com/projects/reac … receiver#/

What do you think about this? It is a bit expensive, but for the project im doing its worth it. You could basically call my project a surveying drone that draws out patterns,

if you go GPS RTK way, my suggestion is to add a very good survey-grade antenna to your system. To reach 1inch accuracy, antenna will be very critical part, because phase center variation.

actually our company make affordable RTK system targeting the UAV market. it’s dual frequency RTK using L1 and L2 band. it’s robust and tolerant to harsh environment. if you have very few knowledge about RTK, we can help

diydrones.com/forum/topics/low-c … e=activity

Winston