Development of a complete data logging system for the muscular and electric torque duty cycle acquisition during mountain e-biking

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Electric bicycles (e-bikes) experienced recently an impressive development, due to the availability of compact and performing electric engines and batteries, like other power twowheelers. This lead to the increase of bicycle users in mountain trails, as assisted pedalling enables less experienced users to afford mountain bike trails typically suitable only to well experienced muscular cyclists. On the other hand, e-bike manufacturers face the rapid raise of demand of electric motors of different power and size. The corresponding search of performing and reliable motors requires the knowledge of typical or massimal duty cycles corresponding to users in different trails. Commercial power meters only measure either the chain total torque or the muscular torque, but not their ratio. The present work reports the development of a complete data logging system applicable to e-bikes for field measurement of motor/muscular torque ratio with respect to assistance levels settings.  </p

Evaluating the effect of anti rotational technologies in oblique helmet impacts using a biofidelic head form

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Head injuries contribute up to 30.5% of all injury-related deaths in the US, representing a potential health issue worldwide. About this, rotational head kinematics were identified as critical to brain damage and specific criteria were developed based on this fact. Therefore, newer test methods and simulations focalized in the rotational component of impacts. Numerical models could provide tissue-level information of simulated impacts, while experimental tests provide quicker results and easier setup. Standardized tests such as ECE.22 make use of metal head forms equipped with a skull accelerometer and gyro. The main limitation is the lack of soft tissues modeling and the possibility to measure only skull kinematics. Instead, more advanced surrogates made for research purposes model soft tissues and could benefit for the measure of brain kinematics and/or pressure waves. Such head surrogates could be an useful experimental tool to validate numerical predictions and to integrate the limited information provided by standard head forms. The aim of the work is to present the advances in the development a bio fidelic replica of the human head, equipped with several and advanced sensors to measure kinematics, pressure waves, and brain stress. The surrogate was then used to perform standardized tests with helmets, and to evaluate the effect of anti-rotational technologies on injury criteria.  </p

Static and fatigue strength characterization of a custom-made Running Prosthetic Foot

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Recent advancements in Running Prosthetic Feet (RPF) have elevated athletes with lower limb amputations to elite performances. However, several aspects regarding static and fatigue structural integrity remain unknown. The absence of standardized test protocols for static and fatigue assessment of RPF, coupled with manufacturers’ limited disclosure beyond stiffness Category, creates an information gap. A method for estimating static and fatigue life properties of RPF is needed. With this aim, a custom-made RPF was chosen as case study to introduce a method for assessing static and fatigue strength of general RPF when very few information is known, and a very small number of specimens are available.  </p

Acquisition of structural loads applied to a backcountry ski boot for the validation of bench tests

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) In the design of ski boot prototypes, two fundamental tests sessions are employed for assessing stiffness & strength. First, in laboratory ski boot bench testing the conventional Flex Index and fatigue life are determined; then, field tests give confirmation of boot performance and safety levels. Frequently, failures observed in the laboratory setting do not necessarily manifest during on-field trials, and vice versa. This adds complexity to the prototypes assessment process, leading to an undetermined overdesign of the ski boots as a precautionary measure. Consequently, a targeted study is needed to collect the field force system acting on ski boot components and to tune accordingly laboratory bench tests. </p

Development and preliminary validation of the numerical model of an instrumented human head replica to assess helmets effectiveness

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Traumatic brain injuries (TBIs) are a leading cause of death and disability worldwide. The availability of sensorized biofidelic head replicas, along with the corresponding validated finite element (FE) models, would provide a new tool for the experimental assessment of helmets effectiveness, in parallel to the detailed FE models of the human head. An instrumented human head replica (IHHR) was developed at the University of Padova in collaboration with Mid Sweden University. The inclusion of sensorised cerebrospinal fluidmeninges-brain simulants in the IHHR enables the assessment of brain damage by means of sensors embedded in the IHHR, thus improving the reproduction of injury mechanisms. The present work reports the development and preliminary validation of the numerical model of this replica, by means of unprotected drop tests on anvils.  </p

Optimising classification of proximal arm strength impairment in wheelchair rugby: a proof of concept study

This study examined the relationship between proximal arm strength and mobility performance in wheelchair rugby (WR) athletes and examined whether a valid structure for classifying arm strength impairment could be determined. Fifty-seven trained WR athletes with strength impaired arms and no trunk function performed six upper body isometric strength tests and three 10 m sprints in their rugby wheelchair. All strength measures correlated with 2 m and 10 m sprint times (r ≥ -0.43; p ≤ 0.0005) and were entered into k-means cluster analyses with 4-clusters (to mirror the current International Wheelchair Rugby Federation [IWRF] system) and 3-clusters. The 3-cluster structure provided a more valid structure than both the 4-cluster and existing IWRF system, as evidenced by clearer differences in strength (Effect sizes [ES] ≥ 1.0) and performance (ES ≥ 1.1) between adjacent clusters and stronger mean silhouette coefficient (0.64). Subsequently, the 3-cluster structure for classifying proximal arm strength impairment would result in less overlap between athletes from adjacent classes and reduce the likelihood of athletes being disadvantaged due to their impairment. This study demonstrated that the current battery of isometric strength tests and cluster analyses could facilitate the evidence-based development of classifying proximal arm strength impairment in WR

Comparison of long jump GRFs and “flex over shape” curves of able-bodied and paralympic amputee athletes

Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024) Running-specific prostheses (RSPs) have enabled people with lower limb amputations to substantially increase their performance in sports competitions. Long jumping is one of the disciplines in which prostheses are enabling athletes to compete at the highest level, achieving performance comparable to that of able-bodied athletes. The aim of the current work is to analyze long jumping biomechanics of two able bodied athletes and of an elite Paralympic transtibial athlete, focusing on Ground Reaction Forces (GRFs) and Roll Over Shape (ROS). Data collected will be used by orthopedic technicians to optimize the RPS setup, by trainers to improve athletes performance and by engineers for in-vitro RSP correct mechanical characterization.</p

Stabilogram Diffusion Analysis results with closed eyes (CE).

<p>(* p<0.01; § p<0.05).</p

Results referred to the static test on the stabilometric platform.

<p>Results referred to the static test on the stabilometric platform.</p

Results referred to the dynamic test on the instrumented platform.

<p>Results referred to the dynamic test on the instrumented platform.</p