# How Long Does It Take to Stop? Are Children Able to Stop on Demand?
## 5 Discussion
Research in this field involves the prediction of movement trajectories of pedestrians [47; 48] and investigates movement characteristics of healthy individuals and those with a unilateral transtibial leg prosthesis [49]. The study confidently determined a steady-state speed with a time to stop of approximately 1.6 s ([PERSON] et al. [50]), while senior citizens and children had average times to stop of 3.25 s (SD = 1.25) and3.14 s (SD = 1.13), respectively. These observations suggest that age group may not be a significant factor in reaction time, although further research is needed to confirm this conclusion. According to [PERSON] et al. (2018), the average time to stop was 0.58 s (SD = 0.31) with a total stopping distance of 0.63 m and a total stopping time of 1.08 s. Notably, the maximum speed recorded by [PERSON] et al. (2018) is comparable with the steady-state speed in the \"walking\" test configuration and the average stopping time of this test configuration. Furthermore, the stopping distance in the \"walking\" configuration ranges from 0.47 to 0.63 m at a steady-state speed of between 3.1 and 4.4 km/h. The study's \"walking\" test configuration indicates that older children have a significantly shorter average stopping distance than younger children. The stopping time required to decelerate from steady-state speed to standstill ranges from 0.84 s to 1.21 s. This range demonstrates a negative correlation with children's age. Moreover, the \"running\" test configuration revealed that the stopping distances of the various age groups were comparable. This finding serves to reinforce the study's conclusions. The stopping distance ranges from 1.72 m to 1.84 m, and the stopping time ranges from 1.17 s to 1.28 s. The time required to decelerate from steady-state speed to standstill decreases with age. These results indicate a clear relationship between age and stopping performance. The temporal dynamics of the acoustic signal's perception and subsequent reaction are not explicitly evaluated; however, these parameters can be inferred from the observed stopping distance and the deceleration phase. The specific braking distance is reduced, and the deceleration values achieved are potentially higher. It has been demonstrated that children can achieve a deceleration ranging from 0.91 m/s\({}^{2}\) (six years old) to 1.57 m/s\({}^{2}\) (9 to 10 years old) in the \"walking\" test configuration. In the \"running\" test configuration, deceleration ranges from 2.24 m/s\({}^{2}\) (six years old) to 3.19 m/s\({}^{2}\) (9 to 10 years old). According to [PERSON] et al. (2018), pedestrians exhibit a median deceleration of 4.2 m/s\({}^{2}\) in response to hazardous situations, demonstrating a clear effort to avoid collisions. The authors conducted a study on vehicle-pedestrian accidents and subsequently analyzed the pedestrian's response prior to the collision. The imminent danger of a collision is quite different from the test configuration, in which an acoustic signal is used to trigger a stopping maneuver. Consequently, the discrepancy in the deceleration rates observed between the present study and those reported by [PERSON] et al. (2018) is not unexpected. While the present study provides significant findings on stopping distances, stopping times, and braking behavior of children aged six to ten years under standardized, child-friendly conditions, the transferability of the results to real traffic situations must be viewed critically. In the controlled test environment, potential sources of distraction--including other road users, unpredictable vehicle movements, noise, and visual stimuli--were systematically minimized. However, it is important to note that these factors are not uncommon in real road traffic and have the potential to significantly influence children's behavior.