Machine control, takeoff and drone data education and news.

Orthographic plan view photo showing how to set up single point GPS site control.

Single Point GPS Site Control: How to Ensure Accuracy & Avoid Errors

Avoid common pitfalls with Single Point GPS site control—learn to ensure stable, accurate results and avoid costly mistakes in grading.

Zach Pieper

GPS machine control calibration screen showing horizontal and vertical control point errors used to verify site accuracy.

Site Control - Principle 4

Your control is set, you calibrated to five points -- now what? Here's how to verify your GPS system is actually reading right before and during grading.

Zach Pieper

Aerial site map showing perimeter site control points around a construction area for GPS machine control and 3D grading accuracy.

Site Control - Principle 2

One control point 0.1' out of tolerance on the wrong side of a project cost a contractor a full site rebuild. The fix was simple and completely avoidable. Principle 2 covers how to distribute GPS control points so your machine control system can actually catch errors before your crew finishes grade.

Zach Pieper

Site plan showing survey control points around a construction site for GPS machine control and 3D grading accuracy.

Site Control - Principle 1

Your machine control model is only as good as your site control. Get that wrong and it doesn't matter how accurate the 3D file is, your equipment is working off a bad reference. Principle 1 is straightforward: hire the engineering firm that designed the project to place your control. Not the low bidder. Not your brother-in-law. The design engineer's surveyor is the only one with all the information and the authority to fix it when something is off.

Zach Pieper

Get Your 3D Grading Under Control

Poor site control is one of the most common (and avoidable) problems encountered by Quantum's clients. Improper site control leads to a

Zach Pieper

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Infographic showing 4 GPS site control principles for machine control: use the design engineer's surveyor, surround the site with control points, calibrate to 5 or more points, and trust but verify with daily checks.

Get Your 3D Grading Under Control: 4 Site Control Principles Every GPS Contractor Needs to Know

Poor site control is the number one problem we see from contractors running GPS machine control. Not bad models or broken equipment. Site control, the first step on every single project. We've seen it cost contractors two weeks of production, turn a correct machine control model on a balanced site into a mysterious site export, and force concrete footings to be redone because the control was rotated 2.8 degrees. Every one of those situations was avoidable.

A screenshot from a drone flight planning interface titled “DJI Mavic 3E Flight Planning for Topographic Survey Mapping” shows a mapped area with a green grid overlay and waypoint markers on the left. On the right, advanced settings display sliders for side overlap ratio (80%), frontal overlap ratio (80%), and margin distance. A note emphasizes that 80% overlap provides good photogrammetry results and should not be set below 70% for 3D mapping. A YouTube play button is centered over the image.

Quantum Flight Pack - DJI Mavic 3E Training Hub

If you're running a DJI Mavic 3E on a construction site, this is where to start. These training videos cover flight planning, RTK setup, camera settings, and calibration — everything you need to get clean topo data that works with your GPS machine control system.