Junji Takahashi

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Junji verified their affiliation via an institutional email.

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• PhD
• Professor (Associate) at Toyohashi University of Technology

In recent years, the demand for mobile robots to operate autonomously in various real-world environments has driven significant advancements in obstacle avoidance research. This progress is fueled by advancements in sensor technologies, such as LiDAR, radar, and computer vision, enabling robots to perceive their surroundings with higher accuracy an...

As autonomous mobile robots have become increasingly popular in our living spaces in recent years, we considered the need to reduce power consumption when taking into account the long hours of operation of the robots. Therefore, we considered using images obtained by image sensors and the universal map (UMap) for indoor location estimation. However...

Universal Map (UMap) is a localization system consisting of a server and a client that matches images obtained from a camera with DB images with coordinate information obtained from a 3D surface model. The problem with UMap is that it is difficult to send correct coordinate information in areas like corridors where fittings such as doors, windows,...

The high computational cost of a typical LiDAR-SLAM makes it difficult to reduce the size and weight of a mobile robot, since a high-performance computer and a large battery are required for long-duration activities.UMap, a cloud-based position estimation system, enables smaller and lighter robots by using a server to perform the computationally ex...

In recent years, robots have been introduced to solve problems such as labor shortages. Localization technology is essential for robots to carry, patrol, and monitor cargo. Although LiDAR-based localization technology is commonly used, localization may fail in environments where LiDAR is not suitable, such as large areas where the laser cannot reac...

In this paper, we propose the use of a learned model for location estimation of 3D CAD maps (Universal Map), a Cloud-Based Localization System. The system performs location estimation using a machine-learning model that uses virtual sensing images created from 3D wireframe maps as training data. To evaluate the effectiveness and feasibility of the...

This paper deals with a problem of map-based localization. When a robot has a pre-constructed map of an environment and explores there with sensing, the localization problem boils down to the problem of finding the closest data pattern to the sensing data from the map. Although, the map quality as well as the sensing data quality greatly affects to...

In localization based on image comparison, enlargement of the image database (DB) is problematic. In this research, we measured the camera posture using an inertial sensor and developed a method to correct the inclination of the captured image. As a result, reduction of the image database was achieved.

In this paper, we propose a solution method of kidnapped problem. In the case where the tracking of the self position becomes impossible after losing the feature point, we will develop a method to identify the position and restore the route by using a cloud type system that can find global localization.

This paper proposed a method of improvement of Localization Accuracy of Cloud-based Localization System using 3D CAD map (Universal Map) by gradient dilation matching. This system only prepares line segment datebase images made from 3D wireframe map in advance to estimate location. This system estimates a location by matching sensing image and data...

This paper deals with map-construction problems for visual localization. Basically, the map is an aggregation of visual landmarks, and it is desirable that such landmarks exist densely and permanently for long-term localization. However, there are no landmarks with these attributes at the same time. In order to solve this problem, we propose a hybr...

This paper proposes a method localizing omnidi-rectional image in Pre-Constructed 3D Wireframe Map. We developed new localization method based on a novel cloud-based localization infrastructure system (UMap). We create an image database from a 3D wire frame and perform localization by matching it with the captured image. We created database images...

Services using Augmented Reality (AR) are widely used with the spread of smartphones. More specifically, there are services that put messages and images into the AR space for sharing them among users who visit the place as well as services that support the user's work by superimposing the work procedure into a real object. In these services, severa...

The development of smartphones and other portable devices has expanded new ways of communication and collaboration both in private and business settings where there are used e.g. for sharing files and other information. However, this communication is not always secure and can be intercepted by a third party in the vicinity. This paper proposes an i...

We propose a novel road monitoring system named YKOB (Your Kinetic Observation Bike) based on participatory sensing. YKOB collects acceleration signals using smartphones worn by cyclists, and analyzes the collected signals to investigate road surface condition. When a bicycle passes on a bump or a dimple, its wheels vibrate. The vibrations are tran...

This paper deals with a road monitoring problem that aims to detect road anomalies with low costs. In order to cope with large area monitoring with low cost, we proposed a participatory sensing based monitoring system named Your Kinetic Observation Bike (YKOB) that only uses a smartphone and a bicycle previously. The monitoring system, YKOB, gather...

This manuscript proposes a novel localization method based on client-server model for an mobile robots and mobile devices such as smartphone. The localization process proceeds as matching calculation between a client sensing image and images in a 2D-image-database one by one. The 2D-database consists of massive amount of images with various viewpoi...

We propose a novel road monitoring system named YKOB (Your Kinetic Observation Bike) based on participatory sensing. YKOB collects acceleration signals using smartphones worn by cyclists, and analyzes the collected signals to investigate road surface condition. When a bicycle passes on a bump or a dimple, its wheels vibrate. The vibrations are tran...

The development of capable smartphones and other portable devices has ushered new ways of communication and collaboration. For example, smartphones are widely used for sharing files with friends and colleagues at meeting or a conference. In this case, conventionally, short-range radio, such as Bluetooth or Wi-Fi are used. Encrypted data can be send...

We aim to realize a novel pen based interface system that provides various digital operations for both low-tech and high-tech people. In this paper, we propose a novel sensor fusion method between IMUs (Inertial Measurement Unit) and strain gauges embedded on a pen device. By using strain gauges for obtaining the correct direction of pen tip moveme...

Quantifying athletes' training helps to improve the efficiency of the training. Though training quantification using multi-modal sensing has been widely applied recently, few cases dealt with anaerobic sports such as short-distance running. This study attempts to provide a quantitative evaluation of the track and field short-distance running using...

The proliferation of smartphones has changed our style of handling personal information and documents. They used to be stored in personal computers, but now they are becoming to be managed in the smartphone. Since this trend accelerates sharing information among many people using smartphones, efficient file transfer among smartphones is important....

This paper discusses quantification method of proficiency of sport skill with Iaido as a subject. Iaido is a modern Japanese martial art using a Japanese sword. A player executes a sequence of actions: drawing the sword from scabbard, cutting a virtual opponent, removing blood from the blade, and sheathing the sword. We measured motions of athlete...

In Japan, comfortable lifestyle and environment realized by abundant electric power broke down after March 11 2011. This has been accompanied by augmentation of heatstroke or hypothermia risks, as well as deterioration of labor productivity. An energy-saving method has been proposed that consist in direct neck cooling or warming to avoid decline of...

We deal with a technical issue of assembling a ring part into a shaft part with the clearance of several micrometers by using a robotic manipulator. This issue is difficult because of deformation of a ring part compared with peg-in-hole assembly. We propose a precise assembly method of a ring part with finger shape to solve this issue. We also prop...

This paper deals with machine learning through interaction with a person. We developed an interactive learning system (LTIP) by concentrating on a specific situation where a user and a robot cooperatively find a lost object in real world. The LTIP consists of a gathering candidate images process, a self-categorizing process based on SOM, and a coop...

Indoor positioning and navigation cannot depend on Global Navigation Satellite System (GNSS) due to the instability or unavailability of its signal. We have designed and implemented Corridor-Level Localization for Indoor Pedestrian Navigation (NAVI Q), a system that performs positioning for indoor pedestrian navigation. Under the concept of indoor...

We often share some files or information among co-located people using mobile phones in our daily lives. Conventionally, we explicitly need to choose users to be connected in the same space. Therefore, defining co-location is useful for many applications. Based on the background, we propose XOLOC, a system to create a co-located mobile-phone users...

We aim to realize a novel pen based interface system that provides various digital operations for both low-tech and high-tech people. In this paper, we propose a novel sensor fusion method between IMUs (Inertial Measurement Unit) and strain gauges embedded on a pen device. By using strain gauges for obtaining correct direction of pen tip movement d...

Crowdsensing has been widely investigated and its applications are being explored. We have used accelerometers embedded in the smartphone carried by bicycle users to detect road surface damages. However, detected damages locations are not aggregated and often, the same road surface damage can be detected several times at different locations due to...

Indoor positioning and navigation technology cannot depend on Global Navigation Satellite System (GNSS) due to the instability or unavailability of its signal. While conventional research activities about indoor pedestrian navigation are enhancing the accuracy of positioning, our approach simplifies a model for navigation and does not necessitate a...

We aim to realize a novel pen based interface system that provides various digital operations for both low-tech and high-tech people. In this paper, we developed an algorithm that associates drawn shapes, such as a circle and a rectangle, with operating commands, such as message input, address input. Using a commercially available digital pen, we c...

This paper deals with machine learning both of recognition and communication. We developed an interactive learning system with concentrating on a specific situation where a user and a robot cooperatively find a lost object in real world. We conducted several experiments to evaluate and analyze the process of interactive learning. We confirmed that...

This paper deals with precise insertion processing (Peg-in-Hole task) for speeding up and increasing flexibility of assembly process in factory automation. When a gap between a peg and a hole is narrower than positioning accuracy of robotic manipulator, it is impossible to succeed the peg-in-hole task by conventional position control methods. Moreo...

We aim to realize a novel pen based interface system that provides various digital operations for both low-tech and high-tech people. In this paper, we propose a new digital pen device which can estimate handwriting trajectories only with embedded sensors, such as a strain gauge and a IMU (Inertia Measurement Unit). First we developed a strain gaug...

We propose a system called YKOB for road authorities to reduce road monitoring cost. It focuses on participatory sensing by cyclists wearing a smartphone. In this paper, we propose a method to classify road signal into three road conditions: positive step (PS), negative step (NS) and convex step (CS). In past studies, we tried to classify road sign...

The number of mobile devices equipped with short-range wireless communication modules such as Bluetooth, in-frared and near field communication (NFC) is increasing rapidly. People always carry the devices and use them for various purposes in their daily lives. For example, mobile users may exchange electronic business card or contact address throug...

In order to reduce a road monitoring cost, we propose a system to monitor extensively road condition by cyclists with a smartphone. In this paper, we propose two methods towards road monitoring. First is to classify road signals to four road conditions. Second is to extract road signal from a smartphone's accelerometer in three positions: pants' si...

This paper deals with a precise insertion processing (Peg-in-hole task) for speeding up and increasing efficiency in factory automation. When the clearance between the peg and the hole is narrower than the positioning accuracy of the robotic manipulator; for example, the former is 10[μm] and the latter is ±20[μm], it is near-impossible to insert th...

We aim to realize a novel pen based interface that provides various digital operations for both low-tech and high-tech people. In this paper, we propose a new digital pen device using strain gauges for detecting the force added on pen tip so as to estimate handwriting trajectories. The prototype system successfully estimated handwriting within 15%...

In recent years, touch-type mobile device such as a tablet and a smartphone has been popularized, but some people do not familiar with them, other people do not use them efficiently. we focus on writing movement and propose “New Generation Digital Pen” that is able to access the Internet more easily and flexibly. In software side, We had constructe...

Iaido is a modern Japanese martial art using Japanese sword. A player executes a sequence of actions: drawing the sword from scabbard, cutting a virtual opponent, removing blood from the blade, and sheathing the sword. Then multiple graders judge his/her mastery of skills subjectively. So, the judgment has possibility of including impropriety on va...

In order to reduce a road monitoring cost, we propose a system to monitor extensively road condition by cyclists with a smartphone. In this paper, we propose two methods towards road monitoring. First is to classify road signals to four road conditions. Second is to extract road signal from a smartphone's accelerometer in three positions: pants' si...

背景：現行のネックウェアはスタンドアロン型のため、駆動状態や制御状態は把握できない。また、不快指数を 用いた自動制御アルゴリズムは個人差を考慮していないという制約が挙げられる。本研究は、スマートフォンと の双方向通信によるウェアラブル個別適合冷暖房システムを提案している。 方法：ネックウェアの駆動状態抽出や制御指令受け取りを無線通信にて行なえるような仕組みを活用し、スマー トフォンにより操作プロトコルとインターフェースを実装した。また、小型無線心拍センサからのデータをリア ルタイムにスマートフォンで処理できるインターフェースも開発し、そのデータから算出できる副交感神経系の 活動指標をもとにネックウェアを制御する仕組みをしている。 結論・考察：副交感神経の活動指標とし、快不快の推定を行い、ネッ...

Crowdsensing is a powerful system to utilize the activities by people carrying mobile phones embedded many kinds of sensors. We have developed a system called vCity Map which uses crowdsensing to visualize the city environment for two kinds of information: sound and road conditions. For sound, we analyze the sound of passing automobiles. Collecting...

Recently, bicycle accidents have been increasing. One of the causes is poor road maintenance because of its high costs. The purpose of this study is the reduction of maintenance cost. We propose a method to detect road damage from cyclists pedaling motion. First, cyclists wear a smartphone in their pants' side pocket and collect acceleration signal...

This paper proposes a novel alternative interface system that enables a user to control an electrical device without his/her hands. The system reads the operational intentions of the user from his/her tongue motions. Although the tongue is the most maneuverable organ besides the hands, it is difficult to detect its motions noninvasively. We develop...

This paper proposes a novel pen type interface system that enables us to send an e-mail only by writing. The system consist of a digital pen which records the trajectory of pen, and a command-classify algorithm which we developed. For sending e-mail, at least 3 commands are required; message command (MC) which assigns the message user wants to send...

This paper proposes the method for assembling a ring into a shaft with the clearance of several micrometers by using a robot manipulator. Assembly by a robot manipulator is difficult compared with other production processes in a factory. This is because there are some problems of the robot positional accuracy, the size tolerance and the deformation...

Patients with muscle weakness such as muscular dystrophy usually need someone’s assistance in their daily activities. In order to reduce the caregiver burden and to improve quality of life (QOL) of the patients, various robotic technologies have been developed. This paper presents an exoskeletal assistance system EMAS II for the patients, which ass...

We propose an assembly algorithm using accurate shape properties of parts for precision assembly. This method realizes the position adjustment between a ring and a shaft passively without RCC devices or complex compliant control. The algorithm requirements are derived from geometrical analysis. The proposed method evaluated experimentally, and the...

This paper proposes an alternative interface system with novel architecture flexible enough to adapt to various types of physically challenged person and able-bodied person, and also capable of connecting to various devices, using a tablet computer as a central system with which a user are interacting. For this interface system surface myoelectrici...

This paper introduces a novel human-computer interface, which uses the electrical signals produced by any residual muscle of persons with a physical disability and translates it to signals to control the cursor of an electronic device. The system also includes electrostimulation signals as feedback to the user to improve performance. The feedback i...

This paper proposes a detection method of tongue motions based on EMG signal around a frontal neck, which is used to control a support device for quadriplegic patient. This method extracts some features of EMG signal that is measured by multiple array electrodes attached on a skin surface of a frontal neck. A Support Vector Machine (SVM) in the met...

This paper proposes a novel human-computer interface system, with architecture flexible enough to adapt to various types of physical disabilities and able-bodied person, and also capable of connecting to various devices via a wireless protocol, using a tablet PC as a central system with which a user are interacting. For this interface system surfac...

This paper proposes a detection method of tongue motions based on BEP signal around a frontal neck, which is used to control a support device for a quadriplegic patient. This method extracts some features of BEP signal that is measured by multiple array electrodes attached on a skin surface of a frontal neck. A Support Vector Machine (S VM) in the...

This paper proposes a novel interface system with using signals of surface electromyogram (sEMG) as inputs for controlling and manipulating mouse pointer. The aim of this system is to extract additional intention of user while user doing deskwork. The characteristic sEMG patterns, which are registered when agonistic and antagonistic muscles contrac...

This paper proposes a new control device based on tongue motions to control and communicate with a support system for a paralyzed patient. We focus on the tongue movements as one of output of human intentions, because the tongue has one of capable parts for the motions and it does not affected by spinal cord damage. The tongue motion is easily obse...

This paper proposes a new control device based on tongue motions to control a physical support system for a paralyzed patient. We focus on the tongue movements as one of output of human intentions, because the tongue has one of capable parts for the motions and it does not affected by spinal cord damage. The tongue motion is easily observed from hi...

This paper describes a communication system by autonomous robots, each of which is equipped with a different type of internal representation respect to same real world. In the advanced robots intelligence, the dimension size of internal representation space should become as large as that of the real world and should be larger than that of sensor sp...

This paper deals with a unified system of fully distributed meshed sensor network and mobile robot cooperation which serves as a sink node. A novel communication timing control employing coupled-oscillator dynamics, named Phase Diffusion Time Division method (PDTD) has been proposed so far, aiming at realization of ad-hoc collision free wireless co...

This paper deals with a unified system of fully distributed meshed sensor network and mobile robot cooperation that serves as a sink node. The meshed sensor network in this paper is composed of static wireless nodes, and is capable of fully distributed peer-to-peer (P2P) ad hoc communication with ZigBee-based protocol. A novel communication timing...

This paper deals with a cooperative object tracking with mobile robotic sensor network. The occlusion problem, which is one of the most important problems of mobile object tracking, will be solve with utilizing the mobile robotic sensor network. Additionally, the high quality information of the object can be observed, since the robotic sensor netwo...

This paper deals with a multihop teleoperation by mobile robotic sensor network in an unknown environment. A mobile robotic sensor network is composed of distributed collection of mobile robots, each of which has sensing, computation, communication and locomotion capabilities. Such a network is capable of changing the network topology in order to g...

This paper deals with a self-deployment of the mobile sensor network in an unknown environment. A mobile sensor network is composed of distributed collection of nodes, each of which has sensing, computation, communication and locomotion capabilities. Such a network is capable of self-reconfiguration of the network topology in order to gather distri...

This paper deals with a cooperative object tracking with mobile robotic sensor network. The occlusion problem, which is one of the most important problems of mobile object tracking, will be solve with utilizing the mobile robotic sensor network. Additionally, the high quality information of the object can be observed, since the robotic sensor netwo...

This paper deals with a self-deployment of the mobile sensor network in an unknown environment. A mobile sensor network is composed of a distributed collection of nodes, each of which has sensing, computation, communication and locomotion capabilities. Such a network is capable of self- reconfiguration of the network topology in order to gather dis...

There are many electric power generators employing dynamos. However, most of them require large mechanical energy input at a time to get large electric power output. This task is not easy for elders because of heavy load. Therefore, we aimed to develop a new ubiquitous power generator suited for light power input. In order to generate large electri...

There are many electric power generators employing dynamos. However, most of them require large mechanical energy input at a time to get large electric power output. This task is not easy for elders because of heavy load. Therefore, we aimed to develop a new ubiquitous power generator suited for light power input. In order to generate large electri...