Workers with disabilities are still lagging in employment rates compared to the healthy workforce. Those workers are also more sensitive for stress at work and possible injuries that are usually connected with non-adequate workplace design. Generally, absenteeism presents high costs for companies and costs can be even higher if injuries at work occur. Therefore, companies face the problem of identifying a suitable workplace for workers with disabilities and supplying the needed requirements. The purpose of our research was to develop a decision support system that would aid in the process of identifying and categorising disabilities of workers, and assigning the most suitable workplace with needed requirements in an integrated work environment to ensure high safety, productivity and satisfaction. The developed decision support system is also a step toward prevention of injuries at work. The usefulness of the system has been shown in a case study of a large-sized production company.
COBISS.SI-ID: 22759190
The nature of the human hand and complex surfaces of the grasped objects usually prevent the direct measurements of displacements, stresses, strains, forces and contact pressure on various anatomical structures in the hand, which would be useful in the field of biomechanics, haptics, ergonomics, etc. This could be mitigated with simulations, especially the FEM, where wide array of results is obtainable. Therefore, we developed a finite element digital human hand model (FE-DHHM), which allows simultaneous studying of bio-mechanics of human hand movement and grasping, analyses of biological tissue deformations, internal stresses, contact pressures and effects of vibration on the hand. Research methods mainly comprised of accurate determination of the human hand FE model geometry using medical imaging, reconstruction of a 3D model in reverse engineering software and correct construction of the FE model in Abaqus software. The developed FE-DHHM has been coupled to motion capture system where joint angles of hand movements from real life grasping scenarios have been fed to the model. Performed simulations have shown that the FE-DHHM is numerically feasible and stable and it shows accurate biomechanical movement and provide accurate results in terms of contact area.
COBISS.SI-ID: 22603798
When developing new handheld products, engineers must consider ergonomics to increase the human-product performance, comfort, and lower the risk of cumulative trauma disorders. Extensive knowledge and lack of computer aided design software in terms of hand ergonomics prevents the improvement of handheld product ergonomics. The main research topic is therefore prehensile hand grasp with a handheld object. The nature of the human hand has prevented direct measurements of stresses, strains, forces, and contact pressure on the hand during movement and grasping. Therefore, several researchers tried to develop a feasible digital human hand model for hand biomechanics and product ergonomics. In this paper we present a viable method to determine realistic human hand movement and use this data to drive the developed finite element hand model for usage in hand biomechanics and product ergonomics. The model geometry has been acquired using medical imaging and appropriate numerical model definition inside finite element software has been defined. Grasping techniques and hand movement were then recorded using motion capture system and were input into the model. Based on numerical tests, the model has proven to be numerically feasible and stable. It shows reasonable biomechanical behaviour of movement and soft tissue deformation and corresponds well with experiments of contact area and pressure measurement and tendon/muscle force.
COBISS.SI-ID: 21697558
Due to certain demanding manual tasks the loads on the human hand can be high, which can cause several disorders, among which are also tendon disorders. Many researchers tried to quantify the loads and provide mathematical models for the tendons of the hand. Since experiments and measurements in vivo are complex and usually not viable, we developed a finite element model of a finger joint, which utilizes tendon/muscle force for the joint movement. Initial simulations of the fingertip finite element model with the developed tendon joint model have shown accurate biomechanical behavior of finger movement and soft tissue deformation. We also compared the results in terms of relationship between tendon force and resulting fingertip (reaction) force from the simulation to an in vivo experiment and have confirmed that the results of the developed finite ele-ment model correspond well to the experimental results.
COBISS.SI-ID: 21645846
Data shows that workers with disabilities are still lagging in employ-ment rates compared to healthy workforce. They report high job insecurity, are less likely to receive employer-based benefits, are more likely to be laid off and are also more likely to work in part-time jobs. Since many companies do not employ ergonomists, employers have a problem to identify a suitable workplace, yet alone to propose the needed accommodations. To mitigate these problems, we developed a decision support system that aids in the whole process of catego-rizing and identifying disabilities of workers and assigns a suitable workplace in an integrated work environment inside the company to ensure high safety, productivity and satisfaction of workers and employers.
COBISS.SI-ID: 22518806