Kohei Sonoda

Hermit crabs perceive the extent of their virtual bodies

A flexible body image is required by animals if they are to adapt to body changes and move effectively within a structurally complex environment. Here, we show that terrestrial hermit crabs, Coenobita rugosus, which frequently change shells, can modify walking behaviour, dependent on the shape of the shell. Hermit crabs walked along a corridor that had alternating left and right corners; if it was narrow at the corner, crabs rotated their bodies to avoid the wall, indicating an awareness of environmental obstacles. This rotation increased when a plastic plate was attached to the shell. We suggest that the shell, when extended by the plate, becomes assimilated to the hermit crabs own body. While there are cases of a tool being assimilated with the body, our result is the first example of the habitat where an animal lives and/or carries being part of a virtual body.

Information transfer in a swarm of soldier crabs

Collective behavior is broadly observed in animal groups such as insect swarm, bird flock, and fish school. Both theoretical studies and field observations have investigated possible underlying principles based on local interaction among individuals in a group without global information via conductors or leaders. Information transferred among individuals would play a key role to understand it. In this study, to investigate how individual in a swarm uses information of its own past behavior or swarm mates’ behavior, we analyzed behavior of soldier crabs Mictyris guinotae in terms of local active information storage and local transfer entropy.

Authority transfer method from automated to manual driving via haptic shared control

As defined by the Society of Automotive Engineers (SAE), drivers are required to resume control from an automated driving system (ADS) in automated Level 2 and 3 driving when requested by the automated system. For example, the driver must resume manual driving control when the functional limitations of the ADS are approaching or have reached. In addition, he or she may also resume manual driving control whenever he/she realizes the functional limits of the system are approaching, or when an ADS malfunction is imminent. In such cases, it is necessary to smoothly transfer driving control to the driver, even when immediate steering actions are needed. Accordingly, this research proposes a method for smoothly transferring authority of steering control from the ADS to the driver in situations where drivers are required to perform quick steering actions. The method is based on a haptic shared control technique that can adjust the strength of the steering control by the ADS. We applied our method to a small electric vehicle and conducted experiments. It was demonstrated that the drivers intention to take over the control could be detected quickly only from the drivers steering operation. It was also suggested that aggressive steering behavior was suppressed with the proposed gain tuning technique, even in cases where the driver was required to engage in engage in immediate steering actions after resuming control.

Passively active-actively passive mutual anticipation in a communicative swarm

In this study, the alternation of the passively active and actively passive attitudes is considered as the basic scheme of communication in a society-like system. We construct a model for swarming behavior based only on mutual anticipation implementing this basic scheme of communication, and we estimate a swarm as a mobile network consisting of mutual anticipation structures. In particular, we show that a mutual anticipation structure can be expressed as a fixed point with respect to equivalence classes in a network and that redundant connections in a mutual anticipation structure can contribute to generating and maintaining a robust and dynamic swarming behavior.

Driver's trust in automated driving when sharing of spatial awareness

Vibrotactile display has been investigated to support drivers monitoring of traffic situation when auto driving. A vibrotactile display was assumed to contribute to driver trust in automation since driver can know the spatial awareness of an automated system to predict or understand the action selection for driving. The display provided the spatial information of close traffic objects with haptic stimulus. The present study considered driving scenes of passing a motorbike when vehicles are approaching from behind. A driving simulator study was conducted to investigate effects of the spatial information and driving behavior of automated system on driver trust. The results showed that the trust was affected by the information and behavior of the system.

Rotating panoramic view: interaction between visual and olfactory cues in ants

Insects use a navigational toolkit consisting of multiple strategies such as path integration, view-dependent recognition methods and olfactory cues. The question arises as to how directional cues afforded by a visual panorama combine with olfactory cues from a pheromone trail to guide ants towards their nest. We positioned a garden ant Lasius niger on a rotating table, whereon a segment of a pheromone trail relative to the stationary panorama was rotated while the ant walked along the trail towards its nest. The rotational speed of the table (3 r.p.m.) was set so that the table would rotate through about 90° by the time that an ant had walked from the start to the centre of the table. The ant completed a U-turn at about this point and so travelled in a nest-ward direction without leaving the trail. These results suggest that the ants persist on the pheromone trail and use visual input to determine their direction of travel along the trail.

Simultaneous Achievement of Workload Reduction and Skill Enhancement in Backward Parking by Haptic Guidance

Advanced driver assistance systems (ADASs) have been developed and have subsequently decreased opportunities for driver skill development because of degraded situational awareness and less activity in the control loop. Beginning drivers must therefore engage in training. The idea has arisen that haptic shared control, which encourages a driver to operate the vehicle properly and with correct timing, should serve as a training system for daily driving. Such a system, however, might degrade performance, comfort, or safety because training aspects might increase the driver workload as a result of error correction feedback. The possibility of lowered usability is not acceptable for ADASs. This study was conducted to develop an assist system that achieves workload reduction and skill improvement. A haptic assistance system that applies guidance torque on the steering wheel was proposed and investigated for backward parking, which is a difficult driving situation. Driving simulator experiments were conducted. Results showed that both support and after-use effects were realized. This study provides knowledge for the development of driving systems using haptic assistant systems for which initial skill influences performance.

Awareness as observational heterarchy

Libet et al. (1983) revealed that brain activity precedes conscious intention. For convenience in this study, we divide brain activity into two parts: a conscious field (CF) and an unconscious field (UF). Most studies have assumed a comparator mechanism or an illusion of CF and discuss the difference of prediction and postdiction. We propose that problems to be discussed here are a twisted sense of agency between CF and UF, and another definitions of prediction and postdiction in a mediation process for the twist. This study specifically examines the definitions throughout an observational heterarchy model based on internal measurement. The nature of agency must be emergence that involves observational heterarchy. Consequently, awareness involves processes having duality in the sense that it is always open to the world (postdiction) and that it also maintains self robustly (prediction).

Displaying System Situation Awareness Increases Driver Trust in Automated Driving

Self-driving systems are expected to become increasingly popular in the foreseeable future. However, a driver who is out of the control loop might reduce overall situation awareness by overly trusting automated driving systems. Alternatively, the introduction of automated driving systems could lead to misuse or disuse. For these reasons, an automated driving system should encourage appropriate driver reliance to achieve social acceptance. Imperfect information of the system sensing range might adversely affect trust. This study used a vibrotactile display with an automated driving system to provide situation awareness. The display contributes to driver trust by enabling a driver to predict or perceive actions selected by the system. The display provides spatial information related to traffic objects by haptic stimulus. The driving scenario of passing a motorbike with vehicles approaching from behind was considered. The results of this driving simulator study demonstrated that the spatial information and the behavior of the system affected trust.

Field of safe travel in swarm

Animals in a group have been considered to have a field or zone to avoid a collision among individuals. The repulsive zone was formalized as a symmetry zone, i.e., a circle in the theories of collective behavior. The present study challenged the theories, since animals would avoid the collision in anticipation that cannot be derived from the symmetry interaction. This study investigated a discrete model consisting of velocity-based “oval” repulsive and long-range attractive zones. This model exhibited highly coherent behavior without explicit alignment force due to asymmetric interaction upon the oval potential. The results would be contributed to future researches in collective behavior and robotics.