Simulating Interactions between Pedestrians, Segway Riders and Cyclists in Shared Spaces Using Social Force Model

Purpose: Personal mobility vehicles (PMVs) are under active development. Most PMVs are wheel-driven, a mode of transport notable for its efficiency. However, wheeled PMVs tend to have poor mobility against negotiating obstacles. The four-wheeled vehicle RT-Mover PType 3 has been developed featuring wheeled legs capable of leg motion. This allows the PMV to overcome uneven terrains, including a step approached at an angle, which ordinary wheelchairs cannot negotiate. Method: This article discusses a gait algorithm in which a leg executes the necessary leg motion when optionally presented with obstacles on a road. In order to lift a wheel off the ground and perform a leg motion, the support wheels must be moved to support points to ensure that the vehicle remains stable on three wheels. When moving towards the target support point, a wheel may encounter another obstacle, and a response method for this case is also described. Results: To assess the gait algorithm, several configurations of obstacles were used for performance tests with a passenger. The capabilities of the PMV were demonstrated through experiments. Conclusion: We proposed a novel gait algorithm for our PMV and realised the proposed motion pattern for PMV-based negotiating obstacles.Implications for RehabilitationOur single-seat personal mobility vehicle, RT-Mover PType 3 features wheels attached on legs capable of performing leg motion, which allows the vehicle to traverse rough terrains in urban areas.We proposed a gait algorithm for RT-Mover PType 3 consisting of a series of leg motions in response to rough terrain. With this algorithm, the vehicle can traverse not only randomly placed obstacles, but also a step approached at an oblique angle, which conventional powered wheelchairs cannot navigate.Experiments with a passenger demonstrated the effectiveness of the proposed gait algorithm, suggesting that RT-Mover PType 3 can expand the mobility and range of activities of wheelchair users.

Modelling shared space users via rule-based social force model

Shared space is a concept of urban street design which implies the creation of a level
\nsurface within the whole road reserve and is aimed at encouraging different road users to
\ninteract spontaneously and to negotiate priority with each other. To build successful shared
\nspaces, traffic engineers can rely at present on specific guidelines as well as technical reports.
\nNevertheless, there is no method available to compute the performance of shared spaces in
\nterms of Level Of Service (LOS).
\nIn order to address this gap, a new indicator of traffic quality for pedestrians is being
\ndeveloped. This measure of performance considers aspects of comfort related to the
\ncrossing, which pedestrians use to go from one side of the roadway to the other. During
\nthis movement, discomfort is generated by the necessity to solve the conflicts with vehicles.
\nTherefore, factors which potentially influence comfort are mathematically formulated.
\nLater, the performance indicator can be calibrated on the basis of the opinion of a group
\nof respondents, who evaluated real-world crossing movements in video sequences. The
\neffectiveness and usability of the developed indicator is demonstrated in an exemplary case
\nstudy. A shared street in the district of Bergedorf, Hamburg (D) is selected and filmed.
\nTo reproduce the interaction of road users and the mechanism of space negotiation, an
\ninnovative modeling approach based on social force model (SFM) is proposed. The model
\nis calibrated and implemented in a Java-based simulation tool. Alternative shared space
\nscenarios, as well as conventional ones with space segregation, are simulated.
\nThe goal of this dissertation is to establish a method to evaluate the performances of
\nshared spaces through traffic microsimulation. This method includes the data survey and
\nacquisition, the definition of performance indicators, the development of a microsimulation
\napproach, the calibration of the motion model on the basis of real-world data and finally
\nthe execution of simulations to collect the results. In addition, this work shows the necessity
\nto employ a comfort-based indicator for pedestrian traffic quality in shared spaces. The
\nbenefits of this approach, with respect to conventional efficiency-based indicators as time
\ndelay, is properly shown in real-world situations and successively demonstrated by help of
\nstatistical methods.

Social force model is one of the well-known approaches that can successfully simulate pedestrians’ movements realistically. However, it is not suitable to simulate high-density crowd movement realistically due to the model having only three basic crowd characteristics which are goal, attraction, and repulsion. Therefore, it does not satisfy the high-density crowd condition which is complex yet unique, due to its capacity, density, and various demographic backgrounds of the agents. Thus, this research proposes a model that improves the social force model by introducing four new characteristics which are gender, walking speed, intention outlook, and grouping to make simulations more realistic. Besides, the high-density crowd introduces irregular behaviours in the crowd flow, which is stopping motion within the crowd. To handle these scenarios, another model has been proposed that controls each agent with two different states: walking and stopping. Furthermore, the stopping behaviour was categorized into a slow stop and sudden stop. Both of these proposed models were integrated to form a high-density crowd simulation framework. The framework has been validated by using the comparison method and fundamental diagram method. Based on the simulation of 45,000 agents, it shows that the proposed framework has a more accurate average walking speed (0.36 m/s) compared to the conventional social force model (0.61 m/s). Both of these results are compared to the real-world data which is 0.3267 m/s. The findings of this research will contribute to the simulation activities of pedestrians in a highly dense population.

Personal mobility vehicles (PMVs), such as an inverted-pendulum vehicle, have been attracting attention as next-generation vehicles for individual use. However, when PMVs travel in pedestrian flows, it is necessary to consider the safety and comfort of pedestrians. This paper investigated a simulation model considering the interaction between multiple PMVs and pedestrians, and analyzed the effects of PMVs in pedestrian flows using the concept of personal space. Furthermore, we proposed an assistance system for PMVs in order to ensure comfort for pedestrians in the presence of PMVs. The simulation results revealed that the avoidance angle and the velocity of PMVs significantly affected the invasion of pedestrians' PSs, and the effectiveness of the assistance system was clearly confirmed.

Safety evaluation of personal mobility vehicles and pedestrians under mixed traffic flow using traffic simulation

Recently, several types of compact personal mobility vehicles (PMVs) have been developed. This study proposes a new type of PMV that can be used as a transportation device, not only for disabled persons, but for the elderly as well. The proposed PMV uses biological signals as a reference value. Myoelectric potential, owing to its ability to reflect human intention with a high probability, was selected from the various types of bioinformation. In this study, we design and fabricate a PMV and consider a feasible utilization method for myoelectric potential.

A vehicle for the individual usage called a personal mobility vehicle (PMV) is investigated in terms of its affinity with pedestrians. A PMV sometimes share the space with pedestrians. Therefore, it is veiy important to ensure the safety and comfort of pedestrians and PMVs in the space. In this investigation, we evaluate the affinity between pedestrians and PMVs using the personal space. The personal space is the space which causes the psychological strain by the approach of others. By using the personal space, the psychological strains of the pedestrians and the PMVs are measured by physical distances. It is shown that the personal space of the two-wheeled dynamically stabilized vehicle has higher affinity with pedestrians than that of the bicycle, which has 2.0 to 2.3 times larger personal spaces for the front, back and side. It is also found that for a pedestrian, the approach of the dynamically stabilized vehicle for the front does not have high impact, however the passing of the vehicle side to the pedestrian causes more discomfort and fear.

A new transportation system, in which personal mobility vehicles (PMVs) and public transports are combined, attracts attention from the viewpoint of environmental loads. Several PMVs including Segway have been developed, however, the use of those vehicles on Japanese public roads is prohibited. As the result, a foldable PMV is developed to be used on Japanese public roads. Although this PMV is designed to run on public roads, it is difficult to avoid danger with the braking system. Therefore, in addition to the deceleration by the open loop control developed by Sakata, we develop a new heel brake that features the backward leaning posture and the movement of the center of gravity. With this brake, even a standing ride PMV can avoid danger by sudden braking. In this paper, we describe the outline and design of the developed brake system and report experimental results of performance evaluation using the heel brake.

For the reduction of environmental load, the support of aged society and the right to mobility, new individual mobility methods are expected. As a method, Personal Mobility Vehicles (PMVs) are investigated and developed these days. Compact PMVs have enough possibility to be used in pedestrian areas for its convenience. It is important to insure safety and comfort to the pedestrians when they share the spaces with PMV users. In this paper, in order to evaluate the influence of PMV on pedestrians, we measured the personal space of the pedestrian who walked against the PMV user. From the experimental results, it was shown that the width of the PMV and height of the step of the PMV significantly affected the personal space of pedestrians. Especially when the width and the height becomes larger, it was found that the front personal space of the pedestrians expanded.

In recent years, a ratio of owner passenger cars in all car-registrations in Japan exceeds more than 70%. Therefore, the owner-cars are as very important means of transportation system. On the other hand, the boarding rate per a vehicle decreases gradually, and, recently, it has become about 1.3 persons per one vehicle. From these situations, a development of the personal mobility vehicle as one of the transportation tools is effective. From the reasons, various kinds of personal mobility vehicles are proposed in recent years. From a viewpoint of road share reduction and of energy consumption, we propose a personal mobility vehicle with rolling-motion such as two-wheeled vehicles. Since the steering system is connected by linkages between steering system and rolling suspension system, driver controls not only steering angle but also rolling angle at the same time using steer angle. As the result, it is shown that the link ratio realizes very large characteristic region by changing according to speed.

Human motion models are finding an increasing number of novel applications in many different fields, such as building design, computer graphics and robot motion planning. The Social Force Model is one of the most popular alternatives to describe the motion of pedestrians. By resorting to a physical analogy, individuals are assimilated to point-wise particles subject to social forces which drive their dynamics. Such a model implicitly assumes that humans move isotropically. On the contrary, empirical evidence shows that people do have a preferred direction of motion, walking forward most of the time. Lateral motions are observed only in specific circumstances, such as when navigating in overcrowded environments or avoiding unexpected obstacles. In this paper, the Headed Social Force Model is introduced in order to improve the realism of the trajectories generated by the classical Social Force Model. The key feature of the proposed approach is the inclusion of the pedestrians’ heading into the dynamic model used to describe the motion of each individual. The force and torque representing the model inputs are computed as suitable functions of the force terms resulting from the traditional Social Force Model. Moreover, a new force contribution is introduced in order to model the behavior of people walking together as a single group. The proposed model features high versatility, being able to reproduce both the unicycle-like trajectories typical of people moving in open spaces and the point-wise motion patterns occurring in high density scenarios. Extensive numerical simulations show an increased regularity of the resulting trajectories and confirm a general improvement of the model realism.

We study the pedestrian motion along a corridor in a nonpanic regime, as usually happens in evacuation scenarios in, e.g., schools, hospitals, or airports, by means of Monte Carlo simulations. We present a model, a combination of the well-known social force model (SFM) and Vicsek model (VM), that takes into account both model interactions, based on the relative position (SFM) and based on the velocity of the particles with some randomness (modulated by an external control parameter, the noise η, VM), respectively. To clarify the influence of the model ingredients we have compared simulations using (a) the pure Vicsek model (VM) with two boundary conditions (periodic and bouncing back) and with or without desired direction of motion, (b) the social force model (SFM), and (c) the model (SFM+VM). The study of steady-state particle configurations in the VM with confined geometry shows the expected bands perpendicular to the motion direction, while in the SFM and SFM+VM particles order in stripes of a given width w along the direction of motion. The results in the SFM+VM case show that w(t)≃t^{α} has a diffusivelike behavior at low noise η (dynamic exponent α≈1/2), while it is subdiffusive at high values of external noise (α<1/2). We observe the well-known order-disorder transition in the VM with both boundary conditions, but the application of a desired direction condition inhibits the existence of disorder as expected. Similar behavior is observed in the SFM case. For the SFM+VM case we find a susceptibility maximum which slowly increases with system size as a function of noise strength. This might be indicative of a order-disorder transition in the range of densities (ρε[1/12,1/9]) and speeds (v_{0}ε[0.5,2]) studied.

In the present paper, we investigate arch-shaped equilibrium solutions in the social force model proposed by Helbing and Molnar (Phys Rev E 51:4282, 1995) and Helbing et al. (Nature 407:487, 2000). The social force model is a system of ordinary differential equations, which describe the motion of the pedestrians under a panic situation. In the simulation of the social force model, we observe an intermittent appearance of arch-shaped structures (i.e. the “Blocking clusters” Parisi and Dorso, Physica A 354:606, 2005; Physica A 385:343, 2007; Frank and Dorso, Physica A 390:2135, 2011) around an exit which block up the flow of pedestrians. To understand such a dynamic behavior, we study arch-shaped equilibrium solutions around an exit under the simplest configuration.

Pedestrian movement modeling and simulation is an important way to formulate an emergency evacuation plan. The performance of the pedestrian movement model directly determines the accuracy of the simulation experiment results. Pedestrian movement in the real world is a very complicated process, and this process is susceptible to a variety of external factors (e.g. road conditions, visibility, etc.) and internal factors (e.g. psychological states, etc.) which making it difficult to model pedestrian movement. The social force model draws on the principles of mechanics and proposes a modeling scheme from the perspective of social force which greatly simplifies the process of pedestrian movement modeling. However, the traditional social force model considers the general situation of pedestrian movement and does not target the emergency evacuation scene, which has certain limitations. In this paper we start with the social force model and introduces the concepts of external guides and internal panic emotions to improves the model. In the scene, the influence of the attraction of the guide and the psychological state of the pedestrian on the movement process of the pedestrian are considered. So that the model is more suitable for the emergency evacuation scene with limited field of vision. It also provides a reference for emergency evacuation plans in public places. We take the subway station as the research object and uses Anylogic software to build simulation experiments. The experimental results show that the improved model we proposed in this paper is less than the traditional model in terms of evacuation time by 8.4%, and is better than the traditional model in terms of exit pedestrian density by 21.5%.