Research of the reliability of a robotic assembly based on the effect of rotation and low-frequency vibrations

Using various physical and technical effects in automatic assembly is a promising tendency to increase the technological reliability of the assembly process. The article presents a method for robotic assembly of cylindrical joints using the effect of rotational motion and low-frequency vibrations. The effect can be achieved by using low-frequency vibrations of the base part with the help of a vibrating device and the rotational movement of the installed part with the help of the rotational movement of the robot out-put link. The paper presented a mathematical model of the dynamics of the robotic assembly process of cylindrical joints. Experiments were set up and carried out to test the effectiveness of the proposed assembly method. The research results affirmed that with a rational technological mode of the robotic assembly process using the effect of rotation and low-frequency vibrations, the probability of jamming is completely eliminated and the assembly force is significantly reduced.

P–096 Real-time ranking of single spermatozoa using artificial vision analysis of complex motility patterns during ICSI aimed at improving fertilization and blastocyst development

Study question Can real-time artificial vision identify beneficial movement patterns of single spermatozoa in a cohort visualized in PVP during ICSI possibly enhancing fertilization and embryo development? Summary answer Artificial vision seems able to identify advantageous movement patterns of individual spermatozoa having a significant impact on both normal fertilization and blastocyst formation. What is known already Spermatozoa isolated from poor semen may reduce the quality of embryo development and blastocyst formation. Normal motility is dependent on general sperm morphology and characteristic movement of the flagellum enabling forward mobility. Spermatozoa roll as they swim. It is known that this rotational motion around their longitudinal axis promotes rheotaxis, which is a mechanism that allows the sperm to navigate to the site of fertilization. Therefore, it is possible that the characteristics of the rotational movement are related to sperm quality. Study design, size, duration Non-intervention study based on a cohort of 132 videos of in-vitro fertilization treatments with ICSI during which the sperm selection process was recorded up to sperm injection. The study was performed at one IVF center within a 6-month period. Injected spermatozoa and their corresponding oocytes were individually assessed from fertilization to blastocyst formation. Videos, where spermatozoa selected for injection could not be identified, were excluded. Relevant outcomes included normal fertilization (2PN), and blastocyst formation. Participants/materials, setting, methods Using a digitizer attached to an optical microscope (640 x 480 pixels), videos were recorded to include the sperm selection process, immobilization, and subsequent injection following standard ICSI protocols. Individual spermatozoa motility features were extracted using a proprietary computer-vision algorithm (SID, IVF 2.0 LTD). The rotational movements of spermatozoa were inferred by computing the variations of the mean intensity of the sperm in the video-sequence across time (MI). Main results and the role of chance Based on SID’s analysis, we found statistically significant differences between the median prominences of the MI of those injected spermatozoa that resulted in successful fertilization in comparison to those with failed fertilization (p-value=0.029, 28 negative fertilization, and 71 positive fertilization) using a one-tailed t-Student test with a significance level of 5%. We also found statistically significant differences between the median prominences of the MI of those spermatozoa that resulted in blastocysts in comparison with the spermatozoa-oocyte cohorts which didn’t reach the blastocyst stage (p-value 0.004, 51 with negative blastocyst formation and 48 with blastocyst formation). Limitations, reasons for caution The size of this database is modest, therefore a larger study with multiple clinics will be necessary to confirm the findings. Large prominence does not necessarily assurance successful fertilization or blastocyst formation since there may be other factors such as oocyte quality or the ICSI technique. Wider implications of the findings: Objective assessment of sperm rotational movement is difficult to quantify and to be objectively assessed during standard sperm selection. Real-time artificial vision tools such as SID could assist embryologists during the sperm selection process for ICSI. Trial registration number NA

Differential Rotational Movement of the Thoracolumbosacral Spine in High-Level Dressage Horses Ridden in a Straight Line, in Sitting Trot and Seated Canter Compared to In-Hand Trot

Assessing back dysfunction is a key part of the investigative process of “loss of athletic performance” in the horse and quantitative data may help veterinary decision making. Ranges of motion of differential translational and rotational movement between adjacent inertial measurement units attached to the skin over thoracic vertebrae 5, 13 and 18 (T5, T13, T18) lumbar vertebra 3 (L3) and tuber sacrale (TS) were measured in 10 dressage horses during trot in-hand and ridden in sitting trot/canter. Straight-line motion cycles were analysed using a general linear model (random factor: horse; fixed factor: exercise condition; Bonferroni post hoc correction: p < 0.05). At T5-T13 the differential heading was smaller in sitting trot (p ≤ 0.0001, 5.1° (0.2)) and canter (p ≤ 0.0001, 3.2° (0.2)) compared to trotting in-hand (7.4° (0.4)). Compared to trotting in-hand (3.4° (0.4)) at T18-L3 differential pitch was higher in sitting trot (p ≤ 0.0001, 7.5° (0.3)) and canter (p ≤ 0.0001, 6.3° (0.3)). At L3-TS, differential pitch was increased in canter (6.5° (0.5)) compared to trotting in-hand (p = 0.006, 4.9° (0.6)) and differential heading was higher in sitting trot (4° (0.2)) compared to canter (p = 0.02, 2.9° (0.3)). Compared to in-hand, reduced heading was measured in the cranial–thoracic area and increased in the caudal–thoracic and lumbar area. Pitch increased with ridden exercise from the caudal–thoracic to the sacral area.

Morphological Changes of the Hip Commonly Associated With Femoroacetabular Impingement Are Not Correlated With Rotational Range of Hip Motion in Elite Soccer Athletes

Background: Morphological changes characteristic of femoroacetabular impingement (FAI) are common in soccer players. However, the clinical relevance of such anatomical variations is still not well-defined. Hypothesis: We hypothesized that high alpha angle values and/or acetabular retroversion index (ARI) are correlated with rotational range of motion (ROM) of the hip and that there are clinical-radiological diferences between the dominant lower limb (DLL) and nondominant lower limb (NDLL) in professional soccer players. Study Design: Cross-sectional. Level of Evidence: Level 3. Methods: A total of 59 male professional soccer players (average age 25.5 years, range 18-38 years) were evaluated in the preseason. As main outcome measures, we evaluated the alpha angle and the ARI and hip IR and ER ROM with radiographic analysis. Results: The measurements taken on DLL and NDLL were compared and a significant difference was found between the sides in the ER ( P = 0.027), where the DLL measures were 1.54° (95% CI, 0.18-2.89) greater than the NDLL. There were no significant differences between the sides in the measures of IR ( P > 0.99), total ROM ( P = 0.07), alpha angle ( P = 0.250), and ARI ( P = 0.079). The correlations between the rotation measurements and the alpha angle in each limb were evaluated and the coefficient values showed no correlation; so also between the ARI and rotation measures. Conclusion: Morphological changes of the femur or acetabulum are not correlated with hip IR and ER ROM in male professional soccer players. ER on the dominant side was greater than on the nondominant side. There was no significant difference in the other measurements between sides. Clinical Relevance: In clinical practice, it is common to attribute loss of hip rotational movement to the presence of FAI. This study shows that anatomical FAI may not have a very strong influence on available hip rotational movement in professional soccer athletes.