FREE STATION TASK WITH DRONE

Using drones with different purposes than only taking photos is nowadays the main direction of drone development. Drones are made for package delivery, people transport, etc. Drone equipped by GNSS RTK and prism can be used as orientation point for the free station. The idea is using drone to get coordinates of total stations inappropriate for GNSS. such as high buildings and forest. The drone can fly above the obstacle causing inappropriate, so the GNSS will compute the position coordinates correctly. Total station will measure distance and angles on prism to get free station coordinates. This article deals with the accuracy of using two points in the free station task. Accuracy of measurement and data is based on real values. Drone can be used as the target if it is not windy, the position accuracy of the target on drone is 5 cm. Wind has no effect on the vertical position accuracy of the the drone. The results show that the same principles and limitations must be observed when measuring the free station task. Horizontal angle between orientation points must be bigger than 100 gon and the zenith angle must be at least 50 gon. The distance between orientation and free station must longer than consequent measured points.

A novel method for determining the X-ray beam angulation of the supraspinatus outlet view

Background Rapid and accurate quantification of the supraspinatus outlet view (SOV) is a clinical challenge. Purpose To quantify the X-ray beam angle of the SOV using the horizontal angle of the subscapular spine line (SSSL) and to further verify the feasibility of this method. Material and Methods A total of 119 patients who underwent shoulder computed tomography (CT) examination were enrolled in the retrospective study. Three-dimensional (3D) CT reconstruction was performed and manually adjusted to provide the position similar to SOV. The rotation angle of the 3D image along the long axis of the human body (marked as β) was obtained. The horizontal angle of SSSL (marked as α) was measured on the anteroposterior localizer image of shoulder CT. Pearson correlation and linear regression correlation analysis were performed. In addition, the first-time success rate between the experience-based group and the measurement-based group were compared to verify the novel method. Results We found a linear correlation between α and β (r = 0.962; P = 0.000). There was no significant correlation between the experience-based group and the measurement-based group in terms of age ( P = 0.500), sex ( P = 0.397), and side ( P = 0.710), but there was a significant statistical difference in the first success rate between the two validation groups (χ2 = 5.808a, P = 0.016). Conclusion This novel quantitative measurement method for determining the X-ray beam angle of SOV using the horizontal angle of SSSL is feasible.

Study the Parametric Effect of Pulling Pattern on Cherry Tomato Harvesting Using RSM-BBD Techniques

Detachment of fruit from the plants with separation force is important in robotic harvesting. Compared with twisting pattern and bending pattern, the pulling pattern for cherry tomato harvesting is more simple, more flexible, and easier to implement in robotic harvesting. It was found that the detachment force is closely related to the location of the fruit separation. However, in the pulling pattern, analysis of the effect of harvesting parameters of cherry tomatoes at the calyx/fruit joint has still not been carried out in depth. In this paper, the goal of this research was to investigate the effect of different harvesting parameters on the minimal detachment force of cherry tomatoes at the calyx/fruit joint. Experiments were designed according to response surface methodology Box–Behnken design by maintaining three levels of three process parameters—grasping angle, horizontal angle, and pitching angle. Results showed that the pitching angle is the most important parameter, and the grasping angle has little effect on the detachment force, and the detachment force was found within the range of 0.58 N to 2.46 N. Results also revealed that the minimum separation force of the cherry tomato harvesting at the calyx/fruit joint was obtained by the optimum conditions of the grasping angle of 68°, the horizontal angle of 135° and the pitching angle of 0°. Moreover, desirability function has also been used to optimize the angle parameters. The confirmation experiments validate the reliability and capability of the developed model.

Application of GIS on Research of Horizontal Refraction in Polygonometry on Network

The article examines the influence of refraction on the results of measuring the horizontal angle in special places. In the conditions of the hot and arid climate of Uzbekistan in the polygonometric network of river banks, according to the results of field experiments, the new version of the developed methodology of the GIS makes it possible to increase the accuracy of measuring horizontal angles and lengths of lines. Significant temperature changes along the water and the coast, on rocks, in the upper layers of sand-concrete pavements are also explained by the properties of the heat and radiation balance.

Correlation Between Three-Dimensional Biometric Weightbearing CT Assessment of Hindfoot Alignment and Conventional Measurements of Adult Acquired Flatfoot

Category: Hindfoot; Ankle; Other Introduction/Purpose: Semi-automatic three-dimensional (3D) biometric weightbearing CT (WBCT) tools have been shown to accurately demonstrate the relationship between the center of the ankle joint and the tripod of the foot. The measurement of the Foot and Ankle Offset (FAO) represents an optimized biomechanical assessment of foot alignment. The objective of this study was to evaluate the correlation between FAO and traditional adult acquired flatfoot deformity (AAFD) markers, measured in different planes. We hypothesized that the FAO would significantly correlate with other radiographic markers of pronounced AAFD. Methods: In this retrospective comparative study, we included 113 patients with stage II AAFD, 43 men and 70 women, mean age of 53.5 (range, 20 to 86) years. Three-dimensional coordinates (X, Y and Z planes) of the foot tripod (most plantar voxel of the first and fifth metatarsal heads, and calcaneal tuberosity) and the center of the ankle joint (most proximal and central voxel of the talar dome) were harvested by two blinded and independent fellowship-trained orthopedic foot and ankle surgeons. The FAO was automatically calculated using the 3D coordinates by dedicated software. Multiple WBCT parameters related to the severity of the deformity in the coronal, sagittal, and transverse plane were manually measured. Results: We found overall good to excellent intra (range, 0.84-0.99) and interobserver reliability (range, 0.71-0.96) for manual AAFD measurements. FAO semi-automatic measurements demonstrated excellent intra (0.99) and interobserver reliabilities (0.98). Hindfoot moment arm (p<0.00001), subtalar horizontal angle (p<0.00001), talonavicular uncoverage angle (p=0.00004) and forefoot arch angle (p=0.0001) were the only variables found to significantly influence and correlate with FAO measurements, with an R-squared value of 0.79. A value of hindfoot moment arm of 19.8mm was found to be a strong threshold predictor of increased values of FAO, with mean values of FAO of 6.5 when the HMA was lower than 19.8mm and 14.6 when the HMA was equal or higher than 19.8mm. Conclusion: We found that 3D WBCT semi-automatic measurements of Foot and Ankle Offset (FAO) significantly correlated with traditional markers of pronounced AAFD. HMA, subtalar horizontal angle, talonavicular uncoverage angle and forefoot arch angle were found to explain 79% of the variations in FAO measurements. FAO Measurements were also found to be more reliable than the manual measurements. The FAO offers a more complete biomechanical and multiplanar assessment of the AAFD, that that accounts for relative positioning of the foot tripod and the center of the ankle joint, representing in a single measurement the three-dimensional components of the deformity.

Surgical approaches for the lateral mesencephalic sulcus

OBJECTIVEThe brainstem is a compact, delicate structure. The surgeon must have good anatomical knowledge of the safe entry points to safely resect intrinsic lesions. Lesions located at the lateral midbrain surface are better approached through the lateral mesencephalic sulcus (LMS). The goal of this study was to compare the surgical exposure to the LMS provided by the subtemporal (ST) approach and the paramedian and extreme-lateral variants of the supracerebellar infratentorial (SCIT) approach.METHODSThese 3 approaches were used in 10 cadaveric heads. The authors performed measurements of predetermined points by using a neuronavigation system. Areas of microsurgical exposure and angles of the approaches were determined. Statistical analysis was performed to identify significant differences in the respective exposures.RESULTSThe surgical exposure was similar for the different approaches—369.8 ± 70.1 mm2 for the ST; 341.2 ± 71.2 mm2 for the SCIT paramedian variant; and 312.0 ± 79.3 mm2 for the SCIT extreme-lateral variant (p = 0.13). However, the vertical angular exposure was 16.3° ± 3.6° for the ST, 19.4° ± 3.4° for the SCIT paramedian variant, and 25.1° ± 3.3° for the SCIT extreme-lateral variant craniotomy (p < 0.001). The horizontal angular exposure was 45.2° ± 6.3° for the ST, 35.6° ± 2.9° for the SCIT paramedian variant, and 45.5° ± 6.6° for the SCIT extreme-lateral variant opening, presenting no difference between the ST and extreme-lateral variant (p = 0.92), but both were superior to the paramedian variant (p < 0.001). Data are expressed as the mean ± SD.CONCLUSIONSThe extreme-lateral SCIT approach had the smaller area of surgical exposure; however, these differences were not statistically significant. The extreme-lateral SCIT approach presented a wider vertical and horizontal angle to the LMS compared to the other craniotomies. Also, it provides a 90° trajectory to the sulcus that facilitates the intraoperative microsurgical technique.

Pullout strength of adjusting pedicle screw with or without self-bone grafting in the previous trajectory using an osteoporotic human vertebral body

Objectives The aim of this study is to explore the pullout strength of adjusting pedicle screw with or without self-bone grafting in the previous trajectory using an osteoporotic human vertebral body. Methods Thirty vertebrae from six cadavers were collected and all of the vertebrae were divided into two groups according to bone mineral density: control group with normal bone mineral density; osteoporosis group with osteoporosis. The osteoporosis group was randomly and evenly divided into five subsamples according to direction of reinsert pedicle screw: the normal angle, sagittal angle, sagittal bone grafting, horizontal angle, horizontal bone grafting. Axial pullout strength testing of the pedicle screw was performed and the maximum axial pullout force (Fmax) was applied to analyse. Result The bone mineral density of the control group was 1.115±0.065 g/cm3, and the bone mineral density of the osteoporosis group was 0.678±0.055 g/cm3, presenting significantly different between the two group (P<0.001). Compared with the control group, the Fmax of the normal angle group was smaller (600.64±43.10 vs 1100.74±49.08 N, P<0.001). Compared with the normal angle group, the Fmax of the sagittal angle group (339.13±38.90 vs 600.64±43.10 N, P<0.001) and the horizontal angle group (342.06±33.01 vs 600.64±43.10 N, P<0.001) were smaller. The Fmax in sagittal bone grafting group was higher than that with non-implanted bone in primary screw canal (492.30±42.06 vs 342.06±33.01 N, P<0.001), and the Fmax of the horizontal bone grafting group was higher than that with non-implanted bone in primary screw canal (502.02± 50.26 vs 342.06±33.01 N, P<0.001). Conclusion The pullout strength of adjusting pedicle screw is seriously decreased in osteoporotic human vertebral body and self-bone grafting in the previous trajectory is an effective remedial measure.

Spinal-pelvic orientation: potential effect on the diagnosis of spondyloarthritis

Objective To assess associations of spinal-pelvic orientation with clinical and imaging-study findings suggesting axial SpA (axSpA) in patients with recent-onset inflammatory back pain. Methods Spinal-pelvic orientation was assessed in DESIR cohort patients with recent-onset inflammatory back pain and suspected axSpA, by using lateral lumbar-spine radiographs to categorize sacral horizontal angle (&lt;40° vs ⩾40°), lumbosacral angle (&lt;15° vs ⩾15°) and lumbar lordosis (LL, &lt;50° vs ⩾50°). Associations between these angle groups and variables collected at baseline and 2 years later were assessed using the χ2 test (or Fisher's exact) and the Mann–Whitney test. With Bonferroni’s correction, P &lt; 0.001 indicated significant differences. Results Of 362 patients, 358, 356 and 357 had available sacral horizontal angle, lumbosacral angle and LL values, respectively; means were 39.3°, 14.6° and 53.0°, respectively. The prevalence of sacroiliitis on both radiographs and MRI was higher in the LL &lt; 50° group than in the LL ⩾50° group, but the difference was not statistically significant. Clinical presentation and confidence in a diagnosis of axSpA did not differ across angle groups. No significant differences were identified for degenerative changes according to sacral horizontal angle, lumbosacral angle or LL. Conclusion Spinal-pelvic balance was not statistically associated with the clinical or imaging-study findings suggesting axSpA in patients with recent-onset inflammatory back pain.

Sound Source Localization Fusion Algorithm and Performance Analysis of a Three-Plane Five-Element Microphone Array

To reduce the negative effect on sound source localization when the source is at an extreme angle and improve localization precision and stability, a theoretical model of a three-plane five-element microphone array is established, using time-delay values to judge the sound source’s quadrant position. Corresponding judgment criteria were proposed, solving the problem in which a single-plane array easily blurs the measured position. Based on sound source geometric localization, a formula for the sound source azimuth calculation of a single-plane five-element microphone array was derived. The sinusoids and cosines of two elevation angles based on two single-plane arrays were introduced into the sound source spherical coordinates as composite weighted coefficients, and a sound source localization fusion algorithm based on a three-plane five-element microphone array was proposed. The relationship between the time-delay estimation error, elevation angle, horizontal angle, and microphone array localization performance was discussed, and the precision and stability of ranging and direction finding were analyzed. The results show that the measurement precision of the distance from the sound source to the array center and the horizontal angle are improved one to threefold, and the measurement precision of the elevation angle is improved one to twofold. Although there is a small error, the overall performance of the sound source localization is stable, reflecting the advantages of the fusion algorithm.