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Foundation piles that are made by concrete 3D printers constitute a new alternative way of founding buildings constructed using incremental technology. We are currently observing very rapid development of incremental technology for the construction industry. The systems that are used for 3D printing with the application of construction materials make it possible to form permanent formwork for strip foundations, construct load-bearing walls and partition walls, and prefabricate elements, such as stairs, lintels, and ceilings. 3D printing systems do not offer soil reinforcement by making piles. The paper presents the possibility of making concrete foundation piles in laboratory conditions using a concrete 3D printer. The paper shows the tools and procedure for pile pumping. An experiment for measuring pile bearing capacity is described and an example of a pile deployment model under a foundation is described. The results of the tests and analytical calculations have shown that the displacement piles demonstrate less settlement when compared to the analysed shallow foundation. The authors indicate that it is possible to replace the shallow foundation with a series of piles combined with a printed wall without locally widening it. This type of foundation can be used for the foundation of low-rise buildings, such as detached houses. Estimated calculations have shown that the possibility of making foundation piles by a 3D printer will reduce the cost of making foundations by shortening the time of execution of works and reducing the consumption of construction materials.

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Modern 3D scanners can measure the geometry with high accuracy and within a short time. In turn, currently produced CNC machine tools allow for very accurate manufacturing; however, processes beyond the machining cycle remain time-consuming. This paper presents the idea and experimental tests of the scanning system in the CNC machine, which allows to speed up on-machine measurements, align clouds of 3D data points with an accuracy close to that of the machine itself, and finally set the workpiece coordinate system for machining. This modern approach is in line with Industry 4.0, combining the terms of data processing, machine vision, manufacturing automation, and human-machine interfaces. The future implementation of the proposed system as an interchangeable tool will allow performing autonomous measurements, inspection, and supervision of the workspace, without engaging the machine operator. The system calibration and experimental results using the industrial 3D scanner and CNC machine are described.

Background: Prismatic cover test (PCT) is a gold standard assessment of strabismus angle, however it has a significant number of disadvantages which are eliminated in Strabiscan device. Methods: Patients with strabismus (n = 30) and a group of healthy subjects (n = 30) were given a detailed history and underwent ophthalmologic examinations (best corrected visual acuity assessment, cycloplegic autorefractometry, biomicroscopic examination of anterior and posterior part of the eye). Each patient and healthy subjects were then subjected to the PCT, and then the presence of strabismus was detected, and its angle assessed using a Strabiscan demonstrator. Statistical analysis was done with Statistica software. Results: No statistically significant differences were noted in the measurements of strabismus angles made by the differing methods. Among the control group, using the Strabiscan demonstration device, low-angle latent strabismus ≤3PD was diagnosed in 83% of patients, and >3PD in 13% of patients. Those using the PCT, on the other hand, diagnosed latent strabismus ≤3PD in only 13% of patients, and latent strabismus with an angle >3PD in 13% of patients. Conclusion: The Strabiscan demonstration device provides quick and accurate assessment of the strabismus angle.