The effects of control-display gain on performance of race car drivers in an isometric braking task

Should Steering Settings be Changed by the Driver or by the Vehicle Itself?

INTRODUCTION

Cars are increasingly computerized, and vehicle settings such as steering gain (SG) can now be altered during driving. However, it is unknown whether transitions in SG should be adaptable (i.e., triggered by driver input) or adaptive (i.e., triggered automatically). We examined this question for road segments expected to require different SG.

OBJECTIVE

This paper aimed to investigate whether SG mode changes should be made by the driver or automatically.

METHODS

Twenty-four participants drove under four conditions in a simulator: fixed low gain (FL), fixed high gain (FH), a machine-initiated steering system, which switched between the two SG levels at predetermined locations (MI), and a driver-initiated steering system, in which the SG level could be changed by pressing a button on the steering wheel (DI).

RESULTS

Participants showed poorer lane-keeping and reported higher effort for FH compared to FL on straights, while the opposite held true on curved roads. On curved roads, the MI condition yielded better lane-keeping and lower subjective effort than the DI condition. However, a substantial portion of the drivers gave low preference rankings to the MI system.

CONCLUSION

Drivers prefer and benefit from a steering system with a variable rather than fixed gain. Furthermore, although automatic SG transitions reduce effort, some drivers reject this concept.

APPLICATION

As the state of technology advances, MI transitions are becoming increasingly feasible, but whether drivers would want to delegate their decision-making authority to a machine remains a moot point.

Advantage and use of S-patch cardio solution in competitive motor sports

BACKGROUND

Motorsport karting has developed into a professional international competition. Kart racing poses a unique set of physiologic challenges for athletes who compete in this sport. Until today no major study has evaluated the physical and cardiac challenge in professional kart racing.

OBJECTIVE

The aim for this study was to measure and analyze heart rate and cardiac rhythm by a mobile, smartphone based ECG (s-patch) on professional kart-race-drivers during actual karting races through annual seasons to test the hypotheses that high g-force and stress could trigger cardiac arrhythmia.

MATERIAL AND METHODS

ECG-data from kart-drivers were acquired during local races, the ADAC Kart-Masters (KZ2), the German Kart Championship (DSKC) and the European Championship Senior CIK-FIA-Serie and analyzed in this observational study. In total, free practice, qualifying practice and 32 races were assessed during the kart season 2019. Data were interpreted by two independent experienced physicians.

RESULTS

The average heart rate (HR) during a selected German Kart Championship (DSKC) race in Genk (Belgium) was 169 beats min-1. The longest R-R interval was 0.72 sec. The average HR during a selected European Championship CIK-FIA-race in Lonato (Italy) was 160 beats min-1. The longest R-R interval was 0.74 sec. The average HR during a selected ADAC Kart-Masters (KZ2) races in Wackersdorf (Germany) was 147 beats min-1. The longest R-R interval was 0.86 sec. In total 32 races could be recorded successful. No couplets or bigeminy cycles were detected. In one other kart racer a supraventricular extrasystole and a ventricular extrasystole was detected. Interestingly, kart-drivers were found to have sinustachycardia throughout the races most likely triggered by emotional and physiological stress during speeding.

CONCLUSION

Professional kart racing drivers had sinustachycardia with heart rates up to 193 beats min-1 during races. This is most likely attributed to a considerably high emotional and physiological stress affecting the cardiovascular system. Episodes of tachycardia positively correlated with mean speed. In the warm-up lap the heart rate was significantly lower in comparison to the race, suggesting that faster driving speed would induce greater cardiovascular stress to professional drivers during actual races. The experimental results showed that the proposed S-patch system provided a good ECG signal quality with accurate measurements even during the kart race and could detect the ECG features of the race in real time. The cardiac interpretation software performs well and is a useful tool to assist clinicians.

Virtual cycling effort is dependent on power update rate

Cycling ergometer protocols are commonly integrated with a virtual reality environment (VRE), especially because of its static position that also allows multiple exercise experiments. Concerning VRE scenarios, visually delayed situations like the ones produced at excessive low update rates can also affect the sense of presence and physiological responses. However, the main interface between the subject and a cycling VRE is the power applied over the crank, and there are only a few experiments to evaluate the effect of delayed situations on this particular interface. Thus, this work aims to investigate the effects of the power update rate (PUR) over the subject`s performance on an avatar-based simulator during a drafting task. A custom cycling VRE was built, and 21 male recreational cyclists (175.9 ± 7.5 cm; 76.5 ± 13.9 kg) were tested at six different PUR levels from 100 to 3000 ms. As a result, PUR affects performance scores (virtual distance, efficiency, and heart rate, p < 0.01) at the given VRE conditions. The case-by-case analysis of the groups reveals that higher update rates always lead to a statistical equivalent or superior performance. Nevertheless, no parameter shows any group difference between 500 ms and lower PUR. These results suggest that virtual cycling protocols should consider PUR and other delay-related mechanisms as possible intervening factors over physiological responses and performance scores.

The Physiology of Auto Racing

INTRODUCTION

Auto racing poses a unique set of physiologic challenges for athletes who compete in this sport. These challenges are not widely recognized due to the limited amount of original research in this field and the diffuse nature of this literature. The purpose of this article is to review the major physiologic challenges of auto racing and summarize what is currently known about athletes in this sport.

CONCLUSIONS

The physical stressors of either driving or servicing the race car are overlaid with particular environmental challenges associated with racing (e.g., thermal, noise, carbon monoxide exposure) that increase the physiological stress on motorsport athletes. Physical stress reflects the muscular work required for car control and control of posture during high gravitational (g) loads: factors that predispose athletes to fatigue. The physiologic effects of these stressors include cardiovascular stress as reflected by prolonged elevation of heart rate, cardiac output, and oxygen consumption in both driver and pit athletes during competition. Psychological stress is evident in autonomic and endocrine responses of athletes during competition. The thermal stress of having to compete wearing multilayer fire suits and closed helmets in ambient temperatures of 50°C to 60°C results in the ubiquitous risk of dehydration. Published data show that both drivers and pit crew members are accomplished athletes with distinct challenges and abilities. There are gaps in the literature, especially in regard to female, older adult, and child participants. Additionally, minimal literature is available on appropriate training programs to offset the physiological challenges of auto racing.

Differences between racing and non-racing drivers: A simulator study using eye-tracking

Motorsport has developed into a professional international competition. However, limited research is available on the perceptual and cognitive skills of racing drivers. By means of a racing simulator, we compared the driving performance of seven racing drivers with ten non-racing drivers. Participants were tasked to drive the fastest possible lap time. Additionally, both groups completed a choice reaction time task and a tracking task. Results from the simulator showed faster lap times, higher steering activity, and a more optimal racing line for the racing drivers than for the non-racing drivers. The non-racing drivers’ gaze behavior corresponded to the tangent point model, whereas racing drivers showed a more variable gaze behavior combined with larger head rotations while cornering. Results from the choice reaction time task and tracking task showed no statistically significant difference between the two groups. Our results are consistent with the current consensus in sports sciences in that task-specific differences exist between experts and novices while there are no major differences in general cognitive and motor abilities.