APPLICATION OF THERMOGRAPHY TO ANALYZE THE EFFECTIVENESS OF ERGOMETER TRAINING

The work determines the degree of thermographic suitability of the method of temperature measurement in people exercising on a rowing ergometer. Thermography is gaining popularity in medical diagnostics by measuring the body temperature. Its main advantages are non-invasive, safe and comfortable for patients. It is widely used in the prevention of breast cancer and treatment of osteoarticular injuries. The basis for the use of thermography in medicine is the phenomenon of thermoregulation of living organisms and the emissive property of the skin, which is similar in value to a perfectly black body.To achieve the set goal, 10 people were trained on the rowing ergometer. During the two series of measurements (before and immediately after), the focus was on two areas of the subjects' body: upper limbs and abdomen.The thermographs obtained were analyzed taking into account the physical and physiological parameters of the players and their experience. The conclusions from them seemed to answer the thesis that the thermographic method is suitable for supporting players in planning and improving their training. It has also been shown that training on a rowing ergometer involves many muscle parties in which an increase in the released metabolic heat takes place

COMPUTER AIDED DESIGN AND STRUCTURAL ANALYSIS OF THE ENDOPROSTHESIS OF THE KNEE JOINT

The paper presents results of the preliminary structural analysis of model of the endoprosthesis of the knee joint. Basics of anatomy and biomechanics of the knee joint were introduced. Based on data from computed tomo-graphy, the model of knee joint was constructed. The prototype of the endo-prosthesis of the knee joint was designed. After determining physical properties of structural materials, the Finite Elements Analysis of the model was conducted under various load conditions. Finally the results of analysis are presented

NUMERICAL ANALYSIS OF SPINAL LOADS IN SPONDYLOLISTHESIS TREATMENT USING PEDICLE SCREWS – PRELIMINARY RESEARCH

The aim of this experimental study was to analyse the influence of lumbar stabilisation used in the treatment of spondylolisthesis on the biome-chanical properties of the human lumbar spine. FEM models were built on the basis of pre-surgical CT scans, routinely used in medical practice. MIMICS software was used to process the results of the neuroimaging study and to create 3D models. Two models were built: with and without a stabiliser. A static load analysis was performed for a normal upper-body load. The simulations allowed to determine the stresses in the individual discs for both models, with and without the transpedicular stabiliser

CYBER-PHYSICAL SYSTEMS TECHNOLOGIES AS A KEY FACTOR IN THE PROCESS OF INDUSTRY 4.0 AND SMART MANUFACTURING DEVELOPMENT

The continuous development of production processes is currently observed in the fourth industrial revolution, where the key place is the digital transformation of production is known as Industry 4.0. The main technologies in the context of Industry 4.0 consist Cyber-Physical Systems (CPS) and Internet of Things (IoT), which create the capabilities needed for smart factories. Implementation of CPS solutions result in new possibilities creation – mainly in areas such as remote diagnosis, remote services, remote control, condition monitoring, etc. In this paper, authors indicated the importance of Cyber-Physical Systems in the process of the Industry 4.0 and the Smart Manufacturing development. Firstly, the basic information about Cyber-Physical Production Systems were outlined. Then, the alternative definitions and different authors view of the problem were discussed. Secondly, the conceptual model of Cybernetic Physical Production System was presented. Moreover, the case study of proposed solution implementation in the real manufacturing process was presented. The key stage of the verification concerned the obtained data analysis and results discussion

Numerical analysis of spinal stabiliser in spondylolisthesis treatment with pedicle screws

The aim of the research on experimental parts was to analyse the influence of the lumbar stabilisation on the strength aspects of the lumbar part of human spine and stabiliser in case of spondylolisthesis treatment. The models were built with the use of pre-surgical CT diagnostics, routinely used in medical practice. MIMICS software was used to process the results of the neuroimaging research and to create a 3D model. Two models were built: one with and the other without a stabilizer. Afterwards, a static load analysis for the load coming from the upper part of the body was done. Analysis was performed using the finite element method (FEA). The performed simulations enabled to determine the stress in particular discs for both models, with and without transpedicular stabiliser

Study of Contact Parameters in Metal-On-Plastic Hip Endoprosthesis with the Analytical-Numerical Method of Contact Mechanics

The purpose is to analyze the influence of the elastic characteristics of the materials of the tribological pair: acetabular–femoral head on the maximum pressures in the hip joint endoprosthesis. Based on the proprietary calculation method of hip joint endoprostheses, an analysis of the impact of UHMW-PE elasticity characteristics (Young's modulus and Poisson's ratio) on the contact parameters was carried out: maximum contact pressure, and contact angle. The study determined the value of contact pressures depending on the changes in the elastic characteristics of UHMW-PE and changes in the geometry of the tribological pair (variable radii of the Grade2TDN head and the UHMW-PE acetabulum). It was found that increasing Young's modulus of UHMWPE increases its stiffness, which causes a noticeable increase in contact pressures in the endoprosthesis. The quantitative and qualitative regularities of this impact were determined. The developed method allows for earlier estimation of contact pressures depending on the external load (patient's body weight), and geometric parameters of the artificial hip joint (diameter of the endoprosthesis head and the acetabulum). This allows you to make a personalized endoprosthesis resistant to damage. It is very important in modern medicine because life expectancy in developed countries is longer and the durability of endoprostheses should be 10–12 years. Hospital statistics show that the need for total hip replacement concerns even younger people. Implantation of a hip joint prosthesis is an invasive and costly procedure, hence the need to produce prostheses with a long service life (over 15-20 years) before re-arthroplasty. The obtained test results showed that the use of an endoprosthesis cup made of UMHW-PE with higher stiffness (high E1 value and low ν value) results in an increase in maximum contact pressures p(0). Increasing the Poisson's ratio in the tested range causes an increase in the contact pressure p(0) even 1.1 times. Increasing the diameter of the head of the D2 endoprosthesis decreases the contact pressure by an average of 2.32 times. On the other hand, a change in the radial clearance in the tribological pair of the hip endoprosthesis from 0.1 mm to 0.2 mm causes an increase in contact pressures by an average of 1.35 times

Study of Contact Pressures in Total Hip Replacement

Total hip arthroplasty is a complex procedure. The achievements of implantology enabled the development of a faithful representation of hip joint physiology as well as the production of materials that can successfully replace damaged natural tissues. The challenge is to correctly select the geometry of the endoprosthesis adequate to the load of the joint. Materials used for endoprosthesis are a metal head and a polymer cup (e.g. PE-UHMW). The main interactions in the endoprosthesis are friction and contact pressure, which must not exceed their limit. Exceeding them causes the destruction of the biomechanical system - plastic deformation of the polymer that is too large and the formation of unacceptable radial clearances. The paper presents the author's empirical method of determining the contact pressures in the tribological pair of the acetabulum - the head of the hip joint endoprosthesis. Based on the obtained research results, it was shown that the developed method gives correct solutions to the contact problem and gives reliable results. The assumption for the work was to prove that empirical methods give correct solutions to contact problems on a par with simulation methods such as FEM. The aim of the work was to demonstrate the correctness of the author's empirical method for determining the maximum contact pressures. Based on the author's developed calculation method of hip joint endoprosthesis contact parameters, the impact on maximum contact pressure and the angle of contact of the joint load was estimated depending on the diameter of the endoprosthesis and radial clearance. The correctness of changing the values of maximum contact pressure from the mentioned parameters was determined. Correspondingly: an increase in joint load causes a linear increase in the maximum contact pressure; increasing the diameter of the endoprosthesis head - their non-linear decrease, and increasing radial clearance - their increase

Tests of Dental Properties of Composite Materials Containing Nanohybrid Filler

Complex composite materials are used in many areas of dentistry. Initially, chemically hardened materials were also used, and in this group nanohybrid composites are highly valued. They are often used today, mainly for the direct reconstruction of damaged hard tooth tissue materials for rebuilding damaged tissues using indirect adhesive techniques. The research was conducted to determine the mechanical properties of materials with nanofillers. The article focuses on methods of important test methods for dental prosthetics: resilience, abrasion, wear test, impact strength, hardness, SEM, and chemical analysis. As part of this work, five different series of hybrid composites with nano-fillers were tested. The mechanical properties of composites, such as compressive strength, microhardness, flexural strength, and modulus of elasticity, depend mainly on the type, particle size, and amount of filler introduced. The obtained test results showed that the type and amount of nanofiller have a significant influence on the mechanical and tribological properties. The introduction of nanofillers allowed us to obtain higher mechanical properties compared to classic materials discussed by other researchers. The study observed a change in vibrations in the IR spectrum, which allowed a comparison of the organic structures of the studied preparations

Using methods of the reverse engineering to carry personalised preoperative stabilisers out on the example of vertebrae of human spine

There is presented the possibility of using modern rapid prototyping methods in the form of reverse engineering on the example of lumbosacral spine of a human spine at the level of L3-L. Reverse engineering techniques were directly used in the generation and processing of point clouds from a real object. The point clouds were generated by using specialised Mimics software and basing on the results of computer tomography and magnetic resonance imaging using. In the next stage of processing, there was the export of the appropriately converted point clouds to STL format, compatible with CAD programs. The reverse engineering process took four steps: digitisation of the real object, using non-invasive imaging techniques (CT, MRI), processing the point clouds from the digitisation stage, construction of a surface model of the real object basing on the processed point clouds, realising of the real object’s copy by using rapid prototyping techniques. In the final stage, the model of the complex spinal’s part was tested to MES strength analysis

STRUCTURAL ANALYSIS OF ARTICULAR CARTILAGE OF THE HIP JOINT USING FINITE ELEMENT METHOD

The paper presents the results of a preliminary study on the structural analysis of the hip joint, taking into account changes in the mechanical properties of the articular cartilage of the joint. Studies have been made due to the need to determine the tension distribution occurring in the cartilage of the human hip. These distribution are the starting point for designing custom made human hip prosthesis. Basic anatomy, biomechanical analysis of the hip joint and articular cartilage are introduced. The mechanical analysis of the hip joint model is conducted. Final results of analysis are presented. Main conclusions of the study are: the capability of absorbing loads by articular cartilage of the hip joint is preliminary determined as decreasing with increasing degenerations of the cartilage and with age of a patient. Without further information on changes of cartilage’s mechanical parameters in time it is hard to determine the nature of relation between mentioned capability and these parameters