Biology subjects

Chizari, M.

Publications and source records attributed to Chizari, M..

3 recordsLinked to original sources

bioRxiv2021

Concept design of a bionic grasp to capture the hand motion

This study has focused on designing a device allowing the user to perform hand exercise motions, in relation with previous methods with good effects in stroke rehabilitation. The project is mainly aimed at designing a low cost, easy to handle and easy to manufacture smart glove to assist users with finger flexion and extensions, which can at the same time transfer data to an application. The methodology used here includes research, design, simulation testing and finalised design. It started with research and investigations on the needs of the users and previous efficient stroke rehabilitation methods. This has been followed with 4 concept designs, which has been tested and evaluated in the next stage for possible optimizations using a computer modelling technique. At the final step, the virtual prototype and product design specification (PDS) of the finalise concept for the interactive device has been illustrated.

bioengineering↗

bioRxiv2020

Smart bionic graspers: background study and design process

This paper has focused on reviewing passive bionic grasper and designing a virtual prototype using a computer modelling technique. The main aim of this study is to review existing research and compare their functionalities. This has been followed by introducing a concept design with suitable components. To start the project, generating a clear overview form the most updated and relative knowledge and information on existing designs was the intention of the study. The concept design part of this study uses an iterative process (similar to the Double Diamond Model introduced by Frances et al (2019)) including Discover, Define, Develop and Deliver to complete the design components. Following the concept design process, the detailed theoretical considerations and the features of components selection were then defined. In Develop Phase, the goal was to decide the final design and generate the computer model using SolidWorks. The fourth phase of process was Delivery leading the design evaluation and validation of the generated model or virtual prototype. By completing the process, it is possible to determine the feasibility of the design and the need for improvement. In final stage of the design, a finite element approach using SolidWorks Simulation was performed on the concept. Final design was decided after comparing the concepts in terms of several considerations. A series of simulations were performed on the design to evaluate the durability of the design and extend its functionality. The results showed that the supporting pad was robust enough when dropped down from 1.5 meters height, while the hinge which connecting the finger straps would need further improvement to avoid failure during its practical loading.

bioengineering↗

bioRxiv2020

Biomechanical Modeling of a Bone Tunnel Enlargement Post ACL Reconstruction

BackgroundBone tunnel enlargement is considered as a potential problem following ACL reconstruction and can cause a fixation failure and complicate its revision surgery. This study evaluates post tibial tunnel expansion in ACL reconstruction using an interference screw. MethodsA series of in-vitro experimental tests on animal bone and tissues were used to simulate post ACL reconstruction. The study believes an unbalanced lateral force can cause a local enlargement on the contact zone inside the tunnel. Grayscale X-ray images were used to assess the screw alignment inside the tunnel. ResultsThey showed a slight misalignment between the screw and the tunnel axis as the tendon strands moved along the side of the tunnel, and the screw had partial contact with the tendon and bone along the tunnel. According to the results, increased stress in the tunnel wall causes tunnel enlargement. Although the tunnel created away from the tibial central axis produced a higher strength, it results in higher stress on the wall of the tunnel which can increase the risk of tunnel expansion. ConclusionsThe current study believes the use of an unguided interference screw insertion potentially increases risks of the misaligned fixation and cause a tunnel enlargement. This risk may be controlled by restricting the post-operative rehabilitation.

bioengineering↗