# Stationary 3D Scanning System for IoT Applications
## 8 Discussion  
Using the third-order polynomial regression fit, the global maximum occurring over a full rotation was calculated. This value was 1480 [-] for an angle of approximately 19.7\({}^{\circ}\), which coincides with the graph shown above. The difference between the largest value (the deviation from the ideal result) and the ideal result, whose value is exactly 1367 [-], for a given measured distance was then 113 [-]. As a result, the largest average measurement error was 3 mm.  
With subsequent attempts to shorten the scanning time, the density of the point cloud decreased with its accuracy, due to the analog nature of the measurement sensor and the frequency of measurements. A significant impact on the average measurement uncertainty, which can be used to describe the accuracy of the grid, is caused by disturbances in the form of, for example, external lighting falling on the sensor.  
Based on the experimental study, the system achieved an accuracy, or more specifically a measurement uncertainty, of about 3 mm. The result depends on the material used to  
Figure 12: The point cloud resulting from an unsuccessful scan of a reflective object.  
Figure 13: A comparison diagram of the results of two separate scanning processes of the same cross-section plane.  
manufacture the scanned object, which can have a significant impact on infrared scanning technology. The positioning of the head itself was set by default by the drive and was 1 mm, which determines the scanning accuracy for the height dimension of the object. This value was determined empirically and is optimal in terms of scanning time and the density of the point cloud itself. The resolution of a given scanning system is about 1 mm, which is top-down determined by the geometry of the infrared sensor lens.  
The scanning accuracy (measurement uncertainty) of the designed 3D scanning system can be compared with examples of existing scanners readily available on the market. One of them is a device called \"EinScan-SP\" from \"Shining 3D Technology' [20], whose design and operation is very similar to the one presented, while due to the technology used (digital camera + structural light), it has a much higher accuracy of 0.05 mm. This is closely related to the price, which increases proportionally and in this case reaches a market value of approximately 1900 $. The cost of the proposed solution is about 450 Euro. The relatively low price of the proposed solution results, among other things, from the use of our own PCB in the control system, based on a microcontroller and our own design, and not on a ready-made single-chip computer or PLC controller.  
It can be concluded that compared to other low-cost systems of this type, the result is very good, because most of the much more accurate measurement systems have a significantly higher price and much larger dimensions. The main advantages of the built system are compactness; high precision in relation to its low cost of implementation, which can be easily improved; a diversified control system allowing full control of the system and communication with it; and the simplicity of assembly and disassembly, which makes it possible to expand the possibilities of scanning objects of larger dimensions.