Experimental study of the S-shaped load element of the soil tillage machine

This article discusses the design of the strut of a tillage machine in the form of an S-shaped power element, using flexible tubular elements (Bourdon springs). Racks of this type are proposed for copying the soil microrelief, maintaining the depth of soil cultivation using a hydraulic drive. The possibility of using the S-shaped rack of the tool of the tillage machine, using flexible tubular elements, to ensure the copying of the soil micro-relief, compliance with the specified working depth, has been experimentally proved. Evaluation of the sensitivity and traction capacity of the S-shaped load-bearing element of the rack will allow us to speak of the ability to create displacements within 120 mm and traction forces up to 1600 N, at a maximum pressure of 6 MPa. Keywords: SOIL TILLAGE, TOOL TILLAGE, FLEXIBLE TUBULAR ELEMENT, DEPTH OF SOIL TILLAGE

Tubular Locomotion and Positioning Using Tip Eversion for Endoscopy

Colonoscopy is a minimally invasive procedure to examine the large intestine using a flexible endoscope. Currently, colonoscopic procedures require physically pushing the endoscope through the large intestine which potentially imparts damaging forces on the intestinal wall, requires a high level of expertise to perform safely, and can require extensive procedure time. This paper presents the use of inverted tubular element locomotion (ITEL) for improved endoscope translation and positioning that works via tip eversion of inverted plastic tubes. Experiments were performed to examine the fluid pressure required for locomotion through a large intestinal model and in both straight and curved paths and determine the optimal tube dimensions for insertion via ITEL. Experiments were then performed to compare intestinal forces during manual and ITEL-based insertion. The experiments established a relationship between the tip eversion pressure and the tube thickness and diameter. In addition, it was found that pressure required for locomotion was only minimally impeded by being enclosed in the intestinal manikin but significantly impacted by the curvature of the turn. Measured insertion forces for ITEL were found to be 10.1% less compared to traditional insertion. These results will aid in the future design and development of ITEL for endoscopic positioning.

Simulation of the stress-strain state of the Ripper foot with a flexible stand

The article presents the results of the calculation of stresses and strains of the structure of the Ripper rack, made in the form of a flexible tubular element, under loading by internal pressure and external force. The finite element method implemented in the ANSYS program was used for the research. The problems of constructing a grid model of a tubular element were solved, displacements of the free end and stresses under the action of internal pressure were determined, the maximum allowable pressure value was found. The horizontal component of the force of influence of the soil on the cultivator, in which there is a loss of stability, is determined. The soil resistance forces were determined by numerical methods depending on the shape of the paw and the speed of movement.

INVESTIGATION OF HYDRAULIC AND VIBROACOUSTIC CHARACTERISTICS OF A PERSPECTIVE VALVE WITH THE WORKING BODY AS A ELASTIC TUBE ELEMENT

The article deals with the design of a perspective throttle valve with an elastic tubular element designed to reduce the vibration and noise of hydraulic systems, which are subject to increased requirements for vibro-acoustic characteristics. The analysis of known similar devices is carried out and the design of the valve-throttle is proved. A detailed analysis of the deformed state of the elastic tubular element is performed and the relationship between the deformations of this element and the hydraulic parameters of the working medium in the flowing part of the valve is shown. The experimental flow characteristics of the valve under study are analyzed, the analysis of which has made it possible to identify the parts of the characteristics at which the constant flow rate remains constant when the pressure drop across the valve changes. The substantiation of this feature of the hydraulic characteristics of a valve with an elastic element is given. The ways of further research directions of the prospective valve are shown.

Simulation of Accident-free Operation of the Modified Cultivator

In the process of pre-sowing tillage, cultivating shovels on various stands are widely used. The type of stand affects the energy and quality indicators of the process. However these stands have one significant drawback: with the increase in the strength of soil resistance, there may be buckling of the stand, which leads to a decrease in the quality indicators of the process. To stabilize the depth of cultivating the soil with cultivating shovels on elastic stands, while maintaining the vibration effect, is possible to achieve through the use of cultivating stands with variable stiffness, made on the basis of a flexible tubular element. The work presents the results of calculating the stresses and strains of the design of the proposed cultivator stand under loading by an external force. For research, the finite element method implemented in the ANSYS program was used. To simulate the movement of a cultivating shovel in the soil, we assumed the following - the treated soil was considered as a continuous medium. The tasks of constructing a grid model of the tubular element were solved, the horizontal component of the force exerted by the soil on the cultivator was determined, at which buckling occurs, the work of the cultivator shovel in the soil is modelled and the permissible speed is determined at which buckling of the flexible tubular element is eliminated.

Novel Inverted Tubular Design for Improved Endoscope Positioning

To detect and treat colorectal cancers endoscopes are commonly used to perform colonoscopies, with an estimated 15 million performed in America every year. Endoscope designs rely on physicians physically pushing the long device into position through the intestine thereupon applying potentially damaging forces to the intestinal wall. To improve endoscopic procedures this paper presents the novel concept of Inverted Tubular Element Locomotion (ITEL) to reduce interaction forces between the endoscope and the intestine wall. Experiments are performed that demonstrate functionality of the tubular design and less than 3.5 kPa to deploy. The tube material thickness has a linear relationship with the force required. This unique design has the potential to enhance patient safety and to improve procedural efficiency.

PENGGUNAAN CONCRETE FILLED STEEL TUBULAR (CFST) SEBAGAI ELEMEN STRUKTUR JEMBATAN PEJALAN KAKI

The concrete filled steel tubular element (CFST) is a hollow steel profile filled with concrete. The axial capacity of CFST elements is greater than its bending capacity. The CFST element will be used as an element structure of pedestrian arc bridge. In this research, we will analyze the structure of arc bridge with variation of height rasio of arc to span of bridge (y/L) and height ratio of floor elevation to span of bridge (h/L). The ratio value y / L = 1/6, produces a larger axial force while the moment that occurs is very small. While the ratio of h / L = 1/7, it produces minimum axial force on the least element of the arch bridge. Keywords: concrete filled steel tubular, pedestrian bridge