This paper presents a model of navigational habituation for human passengers riding an autonomous robotic wheelchair. We present an example on how robot technology is utilized to understand human behavior which is useful to build human-like navigation models. The work consists of three parts, data collection from manual driving participants, habituation modeling and autonomous navigation experimentation. Manual driving data collection consisted of recording human driving control behavior using a robotic wheelchair in a complex labyrinth-like environment, while measuring physiological activity and emotional state via subjective reports (questionnaires). The purpose of this first part was to collect a sufficient representation of the evolution of human driving behavior in a complex environment (23 participants), such that a numerical model could be found to approximate the trend in velocity usage; velocity usage characterizes navigational habituation. The complex environment habituation model was tested and evaluated, on a different set of 16 participants, in a fully autonomous navigation setting where the robotic wheelchair followed a pre-recorded path. Self-reports and physiological measures confirmed that the proposed habitation velocity regulation model provides a more comfortable ride compared to slow and fast pre-defined static velocity profiles.

Observations of fumaroles are important in forecasting volcanic eruptions. However, such observations are dangerous for humans because of volcanic gases and high-temperature steam that surround fumaroles. In previous study, a teleoperated mobile robot was developed to realize remote observations. However, it was observed that typical mobile robots were unable to reach fumaroles on a steep cliff. Therefore, extant research focused on the development of tethered small mobile robots to tackle thsese types of challenging cliffs to observe fumaroles. This study proposes a design of a tethered mobile robot to traverse a steep slope based on the analysis of slip and turnover. A few indoor experimental studies and field experiment were performed to verify the proposed design.

This work proposes a Human-Comfortable Path Planner (HCoPP) system for autonomous passenger vehicles. The aim is to create a path planner that improves the feeling of comfort of the passenger, this topic is different from collision free planning and it has not received much attention. For this purpose, in addition to the shortest distance constraint conventionally used in path planning, constraints related to relevant environmental features are introduced. For straight segments, the constraint is based on the lane-circulation pattern preferred by humans. In curved segments and intersections, the constraint takes into account the visibility. A multi-layered cost map is proposed to integrate these additional constraints. To compute the human-comfortable path, a graph search algorithm was implemented. The evaluation of the proposed approach was conducted by having 30 participants riding an autonomous robotic wheelchair. The paths computed by the proposed path planner were compared towards a state of the art shortest-distance path planner implemented in the navigation stack of ROS. Experimental results show that the paths computed by the proposed approach are perceived as more comfortable.

This paper presents a method for representing acoustic information with point clouds by tying it to geometrical features. The motivation is to create a representation of this information that is well suited for mobile robotic applications. In particular, the proposed approach is designed to take advantage of the use of multiple coordinate frames. As an illustrative example, we present a way to create an audio augmented point cloud by adding estimated audio power to the point cloud created by a RGB-D camera. A few applications of this method are presented.

This paper presents a work on mapping the use of space by humans in long periods of time. Daily geometric maps with the same coordinate frame were generated with SLAM, and in a similar manner, daily affordance density maps (places people use) were generated with the output of a human tracker running on the robot. The contribution of the paper is two-fold: an approach to detect geometric changes to cluster them in similar geometric configurations and the building of geometric and affordance composite maps on each cluster. This approach avoids the loss of long term retrieved information. Geometric similarity was computed using a normal distance approach on the maps. The analysis was performed on data collected by a mobile robot for a period of 4 months accumulating data equivalent to 70 days. Experimental results show that the system is capable of detecting geometric changes in the environment and clustering similar geometric configurations.

This work presents a human-robot cooperative approach for infrastructure inspection. The goal is to create a robot that assists the human inspector during hammer sounding inspections. Hammer sounding is a frequently used inspection technique that detects invisible defects under the surface of concrete by striking the surface with a hammer and listening the resulting sound. The conventional hammer sounding inspection is time-consuming, and there is no convenient way to represent exhaustively the test results. The proposed approach solves these two problems by having an assistant robot following the inspector, and always being able to look at the hammer impact position. The assistant robot accurately estimates the position of the impact in real-time and creates a detailed representation of the test results. Experimental results show the process for creating the detailed inspection report. The accuracy of the human-robot cooperative approach is evaluated for a real world application. The average error of the impact point estimation was 32 millimeters and the standard deviation was 30 millimeters.

This paper presents a study on intention communication in a navigational context using a robotic wheelchair. The robotic wheelchair uses light projection to communicate its motion intentions. The novelty of the work is threefold: the communication of robot intentions to the passenger, the consideration of passenger and robot as a group (“in-group”) [1] who share motion intentions and the communication of the in-group intentions to other pedestrians (the “out-group”). A comparison in an autonomous navigation task where the robotic wheelchair autonomously navigates the environment with and without intention communication was performed showing that passengers and walking people found intention communication intuitive and helpful for passing by actions. Evaluation results significantly show human participant preference for having navigational intention communication for the wheelchair passenger and the person passing by it. Quantitative results show the motion of the person passing by the wheelchair with intention communication was significantly smoother compared to without intention communication.

This work proposes a model for human habituation while riding a robotic wheelchair. We present and describe the concept of human navigational habituation which we define as the human habituation to repetitively riding a robotic wheelchair. The approach models habituation in terms of preferred linear velocity based on the experience of riding a wheelchair. We argue that preferred velocity changes as the human gets used to riding on the wheelchair. Inexperienced users initially prefer to ride at a slow moderate pace, however the longer they ride they prefer to speed up to a certain comfort level and find initial slower velocities to be tediously “too slow” for their experience level. The proposed habituation model provides passenger preferred velocity based on experience. Human biological measurements, galvanic skin conductance, and participant feedback demonstrate the preference for habituation velocity control over fixed velocity control. To our knowledge habituation modeling is new in the field of autonomous navigation and robotics.

The technology for web services has facilitated composition of a new service by combining existing services. The resulting composite service is required to guarantee Quality of Service (QoS), such as price, in addition to the demanded function. Each composite service faces computationally-expensive service selection by exploring enormous service combinations for optimization of a utility function and satisfaction of global constraints. In addition, each concrete service has difficulties in determining QoS that is profitable while attractive for customers, or composite services. Specifically, information on rival services is generally secret and changeable, which is required for the optimal decision. In response to these problems, this paper proposes an algorithm for service selection using Vickrey auction. In the first phase of the proposed algorithm, the composite service selects some best concrete services through the reverse Vickrey auction, only considering the utility function. In the second phase, the global constraints are satisfied through adjustments based on the Vickrey auction. The proposed algorithm avoids full exploration of services combinations for efficient computation, while encouraging providers to declare their best QoS without caring about extra profit.

For the construction of the mobile robot system, it is necessary to determine a lot of parameters like the feedback gain and the clip parameters of artificial saturation. And it is difficult to decide suitable parameters by analytical technique because of its non-linearity and complexity. In this paper, we propose the method of the mobile robot control system parameter design by a numerical simulation and heuristic optimization using the enough computer power. We describe the model of the system as iterative numerical calculation instead of analytical time function. This model can suit the real control system, and it is straightforward to be built. And we show the experimental results of the automatically decided feedback gains by using proposed method for the linear feedback trajectory tracking controller of the small-sized autonomous mobile robot system, which runs in relatively high speed up to 5 meters per second as an example.

The developments of differential and linear cryptanalysis methods were capable to breach the security of the DES cipher. Accordingly, the National Institute of Standards and Technology (NIST) issued a new standard named Advanced Encryption Standard (AES) which had SPN (substitution permutation network) structure as a new next generation code standard method as a replacement for DES. However, this method has also found a hole in the security level of the AES, especially in the AESpsilas S-box. This paper proposes a new mutable nonlinear transformation algorithm for AES S-box to enhance the complexity of the S-Box's structure called M_S-box that effectively provides an optimal degree of resistance against differential cryptanalysis and especially the linear cryptanalysis. The structure of the AES S-box has been expanded and modified to be congruent with the proposed algorithm and to obtain good nonlinearity of the S-box. The Cryptanalysis of the model is based on the maximum average differential probability (MADP) and maximum average linear hull probability (MALHP). The results show that proposed model significantly improves MADP and MALHP. Furthermore, the results that have been obtained exhibit good enough confusions to achieve high security level.

Parameter tuning of force control is important for successful robotic assembly and ensuring high efficiency operations. In this paper, we present a method of designing damping control parameters for general assembly operations by considering the cycle time. In this method, optimal parameters are obtained through iterative simulations of assembly operations because it is difficult to estimate the cycle time analytically. We have applied the method to clutch assembly, which is a complicated insertion of a splined axis into movable toothed plates, and demonstrate how the operation can be sped up using the obtained parameters.

Multiple fiber ring (MFR) networks employing the optical path (OP) concept are discussed to realize robust networks. The architecture is superior to that discussed in several testbeds, with respect to fault recoverability. Both the OP based and non-OP based MFRs can develop several architectures, each of which provides different performance regarding network resource utilization. The required node system scale can be a good measure in determining the network performance. Network design simulations, varying path distribution patterns, have been performed and they elucidated the criteria for selecting the most suitable architecture in terms of resource utilization.

To realize a large scale and robust photonic transport network, this paper proposes a network protection strategy and maintenance signaling flow for WDM optical path transport networks. The network protection strategy is applicable for mesh-type WDM optical path transport networks, and the OA&M flow that is required for the network to recover from failures are clarified. The proposed OA&M flow does not rely on the OP-AIS (optical path alarm indication signal) generation method. This signaling method can also be applied to the all-optical type network.

This paper demonstrates our previously developed large-capacity optical path cross-connect (OPXC) system. The major hurdles to be cleared are (1) establishment of a highly modular architecture that facilitates hardware design and upgrading and (2) the development of an OPXC demonstrator designed to achieve 320-Gbit/s throughput capacity. Due to the use of planar lightwave circuit technologies, compact size packaging for an 8/spl times/16 delivery-and-coupling type optical switch and an arrayed-waveguide grating for a wavelength-demultiplexer are achieved. The dense packaging of the four-channel optical regenerators (3-R function regenerator) makes it possible to realize a large-capacity OPXC that can offer high quality transmission and ensure robustness in terms of multiple node connection. Performance test results confirm the validity of the system design and the feasibility of 320-Gbit/s OPXC implementation.