Development and validation of a set of wheelchair finite element models in frontal, side, and rear impact conditions.

Objective: The objective of this study was to develop and validate finite element (FE) models of commercial manual and power wheelchairs, as well as related test fixtures and tiedown hardware, to provide tools for designing integrated wheelchair seating stations for automated and other vehicles.

Methods: The manual wheelchair model is based on a Ki Mobility Catalyst 5, and the power wheelchair is based on a Quantum Rehab Q6 Edge 2.0 with Synergy Seating.

Efficient injury risk predictions for a diverse population using parametric human modeling and inducing points in Gaussian processes.

Objective: The objective of this study is to use parametric human modeling and machine learning methods to identify representative occupants that can account for injury variations among a more diverse population with a limited simulation budget.

Method: A maximal projection method was used to sample 100 occupants, considering the variations in stature, weight, and sitting height. An automated mesh morphing method was used to morph the THUMS v4.

Optimizing frontal impact occupant protection systems for passengers seated in wheelchairs.

Objective: The advent of automated vehicles (AVs) provides an opportunity to design integrated wheelchair seating stations that provide an equivalent level of safety for occupants using wheelchairs as those using vehicle seating. This study designed a frontal occupant protection system for an integrated second-row wheelchair seating station that includes optimized airbags and seatbelt systems.

Methods: MADYMO models were used to optimize belt geometry for a midsized male ATD seated in a surrogate wheelchair fixture, with and without inclusion of a Self Conforming Rearseat Air Bag (SCaRAB).

Child occupant safety in unconventional seating for vehicles with automated driving systems.

The objective of this study was to use computational models to study how unconventional seating positions and orientations in vehicles with Automated Driving System (ADS) may affect occupant response metrics of children with various restraint conditions. A literature review was first conducted to frame a simulation plan, including selections of surrogate ADS-equipped vehicles, potential seating arrangements, impact scenarios, anthropomorphic test device (ATD) models, and child restraint system (CRS) models that are relevant to the selected ATD models. Due to the lack of impact tests with child ATDs and CRS in farside, oblique, and rear impacts, 17 sled tests were conducted with CRS harness-restrained ATDs and vehicle belt-restrained ATDs in frontal, farside, oblique, and rear impact conditions.

Inspiratory response and side-effects to rapid bilateral magnetic phrenic nerve stimulation using differently shaped coils: implications for stimulation-assisted mechanical ventilation.

Background: Rapid magnetic stimulation (RMS) of the phrenic nerves may serve to attenuate diaphragm atrophy during mechanical ventilation. With different coil shapes and stimulation location, inspiratory responses and side-effects may differ. This study aimed to compare the inspiratory and sensory responses of three different RMS-coils either used bilaterally on the neck or on the chest, and to determine if ventilation over 10 min can be achieved without muscle fatigue and coils overheating.

Improving protection system for wheelchair-seated occupants in vehicle side impacts.

Previous research on occupant protection systems for wheelchair-seated occupants focused on frontal impacts, while similar studies on side impacts are very limited. The objective of this study was to identify the major injury concerns for wheelchair-seated occupants in side impacts and develop restraint systems to mitigate such injury concerns. Seven sled tests in side impact conditions were first conducted at 30 km/h with a 24 g peak deceleration.

A Literature Review of Wheelchair Transportation Safety Relevant to Automated Vehicles.

This literature review summarizes wheelchair transportation safety, focusing on areas pertinent to designing automated vehicles (AVs) so they can accommodate people who remain seated in their wheelchairs for travel. In these situations, it is necessary to secure the wheelchair to the vehicle and provide occupant protection with a Wheelchair Tiedown and Occupant Restraint System (WTORS). For this population to use AVs, a WTORS must be crashworthy for use in smaller vehicles, able to be used independently, and adaptable for a wide range of wheelchair types.

Case Studies in Physiology: Cardiopulmonary exercise testing and inspiratory muscle training in a 59-year-old, 4 years after an extrapleural pneumonectomy.

This case report characterizes the physiological responses to incremental cycling and determines the effects of 12 wk of inspiratory muscle training (IMT) on respiratory muscle strength, exercise capacity, and dyspnea in a physically active 59-yr-old female, 4 years after a left-sided extrapleural pneumonectomy (EPP). On separate days, a symptom-limited incremental exercise test and a constant work rate (CWR) test at 75% of peak work rate (WR) were completed, followed by 12 wk of IMT and another CWR test. IMT consisted of two sessions of 30 repetitions twice daily for 5 days per week.

Effects of the Elevation Training Mask® 2.0 on dyspnea and respiratory muscle mechanics, electromyography, and fatigue during exhaustive cycling in healthy humans.

Objectives: Examine the effects of the Elevation Training Mask® 2.0 (ETM) on dyspnea, and respiratory muscle function and fatigue during exercise.

Design: Randomized crossover.

Dynamic metrics to differentiate booster performance.

Objective: The purpose of this research was to explore candidate booster performance metrics that may have the potential to identify less effective booster systems, because current FMVSS No. 213 booster performance requirements can be met without a booster.

Methods: To provide a more realistic test environment, dynamic testing was performed using a surrogate seat belt retractor on the most recent preliminary design update proposed for the FMVSS No.

Restraint systems considering occupant diversity and pre-crash posture.

Objective: Use volunteer data and parametric finite element (FE) human body models to investigate how restraint systems can be designed to adapt to a diverse population and pre-crash posture changes induced by active safety features.

Methods: Four FE human models were generated by morphing the midsize male GHBMC simplified model into geometries representing a midsize male, midsize female, short obese female (BMI 40 kg/m), and large obese male (BMI 40 kg/m) based on statistical skeleton and body shape geometry models. Each human model was positioned in a generic vehicle driver environment using two occupant pre-crash postures based on volunteer test results including one resulting from 1-g abrupt braking events.

Reliability of diaphragm voluntary activation measurements in healthy adults.

Voluntary activation can be used to assess central fatigue of the diaphragm after tasks such as exercise or inspiratory muscle loading. Cervical magnetic stimulation (CMS) of the phrenic nerves elicits an involuntary contraction, or twitch, of the diaphragm. This twitch is quantified based on a measure of transdiaphragmatic pressure and can be used to evaluate diaphragm contractile function and diaphragm voluntary activation (diaphragm-VA).

A multidimensional assessment of dyspnoea in healthy adults during exercise.

Purpose: (1) To determine whether healthy humans can distinguish between the intensity and unpleasantness of exertional dyspnoea; (2) to evaluate the reliability of qualitative dyspnoea descriptors during exercise; and (3) to assess the reliability of the Multidimensional Dyspnoea Profile (MDP) METHODS: Forty-four healthy participants (24M:20F, 25 ± 5 years) completed maximal incremental cycling tests on three visits. During visit 1, participants rated the intensity and unpleasantness of dyspnoea simultaneously throughout exercise using the modified 0-10 category-ratio Borg scale. On visits 2 and 3, participants rated either the intensity or unpleasantness of dyspnoea alone at the same measurement times as visit 1.

Should airbags be deactivated for wheelchair-seated drivers?

Objective: Field data have shown significant benefit from driver airbag for occupant protection in frontal crashes. However, vehicle modifiers almost always permanently deactivate airbags for wheelchair-seated drivers. The objective of this study was to conduct sled tests and computational simulations to answer whether driver airbags should be deactivated for drivers seated in wheelchairs.

Effects of the Turbine™ on Ventilatory and Sensory Responses to Incremental Cycling.

Introduction: The Turbine™ is a nasal dilator marketed to athletes to increase airflow, which may serve to reduce dyspnea and improve exercise performance, presumably via reductions in the work of breathing (WOB). However, the unpublished data supporting these claims were collected in individuals at rest that were exclusively nasal breathing. These data are not indicative of how the device influences breathing during exercise at higher ventilations when a larger proportion of breathing is through the mouth.

Short-term effects of Lumacaftor/Ivacaftor (Orkambi™) on exertional symptoms, exercise performance, and ventilatory responses in adults with cystic fibrosis.

Rationale: Lumacaftor/ivacaftor (LUM/IVA) modestly improves lung function following 1 month of treatment but it is unknown if this translates into improvements in exercise endurance and exertional symptoms.

Methods: Adult CF participants completed a symptom-limited constant load cycling test with simultaneous assessments of dyspnea and leg discomfort ratings pre- and 1 month post-initiation of LUM/IVA.

Results: Endurance time, exertional dyspnea and leg discomfort ratings at submaximal exercise did not change significantly.

The Impact of Cycling Cadence on Respiratory and Hemodynamic Responses to Exercise.

Purpose: The physiological consequences of freely chosen cadence during cycling remains poorly understood. We sought to determine the effect of cadence on the respiratory and hemodynamic response to cycling exercise.

Methods: Eleven cyclists (10 males, 1 female; age, 27 ± 6 yr; V˙O2max = 60.