In recent years, more and more hospitals, rehabilitation centers, and even some primary and secondary school physical examinations are equipped with a device called “plantar 3D scanner”.
Take off your shoes and socks, and in just a few seconds, you can generate a “plantar map” you have never seen before: arch height, sole width, heel angle, center of gravity distribution… Clear and intuitive, even the ups and downs of your soles are clear at a glance.
Many people will ask when they experience this test for the first time: “This machine is so advanced, do I need to stand still? Or can I shake it naturally and relax?”
The answer is: you must stay still, and the more stable the better.
Why do you say that? This starts with the working principle of plantar 3D scanning.
1. Why is it called “3D scanning”?
The so-called “plantar 3D scanning” is not as simple as taking a photo. Its core principle is – laser structured light projection + deep visual modeling technology.
Specifically, the instrument emits laser or infrared beams in multiple directions, hitting every tiny area on the sole and side of the foot; at the same time, the built-in high-precision camera captures the reflection path and deformation of these lights, and then builds a complete three-dimensional foot model with real height, width, and curvature.
The biggest advantage of this method is that it can obtain millimeter-level precision foot shape data in a few seconds without contact or mold. And these data are the important basis for the subsequent production of corrective insoles, customized shoes, and foot rehabilitation training.
2. Why must you stay still when scanning?
Because laser scanning is a technology that relies on fine ranging and spatial modeling. If you move, the result will change.
There are three specific reasons:
Movement will interfere with light reflection and modeling accuracy
When you move your foot, the position where the laser is irradiated will also change, and the reflected light will shift, causing the system to be unable to accurately identify certain contours or edge positions, ultimately causing the scanned image to be blurred, distorted, or even missing.
Changes in plantar pressure will affect the shape of the arch
Once the center of gravity of the body shakes during standing, the force area of the sole will also change, and the arch height, forefoot support point, medial longitudinal arch and other structures that can be accurately captured will also change, causing data distortion.
System modeling requires a stable reference point
Three-dimensional scanning relies on the superposition of multiple frames of images to construct a complete model. If the standing is unstable during the process, the system will find it difficult to identify continuous feature points, and the modeling logic will be wrong.
Therefore, standing still is one of the key steps for the success of three-dimensional scanning.
3. How long do you need to stay still during standard testing?
At present, most plantar three-dimensional scanning equipment only needs 5 to 10 seconds of stable standing time when working.
The specific process is as follows:
Take off your shoes and socks, and stand barefoot in the center of the scanning platform
Aim at the heel positioning line or support area according to the prompts
Look forward, let your arms hang naturally, and keep your whole body still
After the staff starts the equipment, the system will complete the modeling in a few seconds
After the scan is completed, your 3D foot model image and data analysis report will appear on the screen
The whole process is fast, painless, and contactless, and it is very friendly to children, adults, and the elderly. The only “effort” is to stay still in those few seconds.
4. How important is the scanning result?
Don’t underestimate this simple action. Accurate foot scan data can solve many physical problems for you:
Determine whether you have flat feet, high arches, valgus, or inversion
Identify asymmetric length and width of the feet to prevent foot wear or deviation
Serve as a reference for foot fatigue, knee pain, and abnormal gait
Customize insoles, sports shoes, and corrective supports that fit the foot shape
Prevent posture deviation during children’s growth and intervene early
In rehabilitation medicine, doctors will give gait assessments, insole customization suggestions, and even posture correction plans based on scan data. These are all based on “high-quality original models”, and being still is the “first hurdle” to ensure data accuracy.
