Hiroshi Ishida

Tokyo University of Agriculture and Technology | TUAT · Graduate School of Bio-Applications and Systems Engineering (BASE)

The aim of this research project is to attain accurate gas-source localization in outdoor environments with large wind fluctuations. For this purpose, we propose to use a long short-term memory deep-learning framework to time-series data collected by a sensor network consisting of multiple gas sensors and an anemometer. This paper describes impacts...

To better understand the dynamics in hazardous environments, gas distribution mapping aims to map the gas concentration levels of a specified area precisely. Sampling is typically carried out in a spatially sparse manner, either with a mobile robot or a sensor network and concentration values between known data points have to be interpolated. In th...

This paper reports the use of the first gas dispersion simulator capable of introducing large wind fluctuations into simulations. The proposed simulator enables testing of a modification made to a gas source localization algorithm in a realistic scenario in order to study how the change affects it. Gas source localization in an outdoor environment...

This paper proposes a human olfactory interface that modulates airborne odors and enables the users to selectively sniff only the odors that they want. Air containing odors is collected and exposed onto plural types of adsorbents for separation and concentration of odorous substances contained in the odors. The desorbed substances from the adsorben...

Introduction The human sense of smell plays important roles in various scenes in everyday life although we are unconscious of its importance in most cases. For example, olfaction provides alerts that lets us notice dangers or risks such as a fire and rotten food. Savory food smells and comfort flower fragrances make our lives richer. However, it is...

In this paper, the development of a quadcopter for gas sensing in a landfill site is reported. When a quadcopter with a long diagonal length flies at a low altitude, the downdrafts from the four rotors reach the ground without merging with each other, and then, spread radially along the ground surface. These downdrafts collide with each other at th...

This paper describes the utilization of the downwashes of multicopters for gas-sensing applications. Multirotor drones are an attractive platform for sensing applications. Their high maneuverability enables swift scanning of a target area with onboard sensors. When equipped with a gas sensor and used for gas-sensing applications, however, the stron...

Here we report on Tutorials and Sniffest from the ISOEN 2019 conference program. Sniffest is the student competition for machine olfaction. In ISOEN 2019, student teams brought a custom-made robot equipped with gas sensors, and competed in time trials in which the robots tried to track an odor trail laid on the floor. A short review is also reporte...

Here, we report on computational fluid dynamics (CFD) simulations conducted to develop a chemical sample collection device inspired by crayfish. The sensitivity of chemical sensors can be improved when used with a sniffing device. By collecting fluid samples from the surroundings, all solute species are also collected for the sensor. Crayfish gener...

An olfactory display is a device that presents odors to the user’s nose so that he/she can get rich virtual reality experience. The aim of this research project is to develop an olfactory display that can generate multiple different odors. Currently, the user needs to set multiple pre-mixed odorants to an olfactory display to switch between differe...

Here we report our research efforts on farm mechanization. From the animal welfare point of view, there have been increased demands for cage-free farming of poultry birds such as egg laying hens. However, cage-free operations generally require more labor than to rear hens in battery cages.When a flock of newly hatched chicks are introduced into a c...

Convolutional Long Short-Term Memory Neural Networks (CNN-LSTM) are a variant of recurrent neural networks (RNN) that can extract spatial features in addition to classifying or making predictions from sequential data. In this paper, we analyzed the use of CNN-LSTM for gas source localization (GSL) in outdoor environments using time series data from...

This paper reports on olfactory amplifying systems and reviews related technologies. We have developed two types of olfactory amplifying systems that allow the user to sense smells with amplified sensitivities. In the first system, odor molecules drifting in the air are collected using an adsorbent material. The concentrated odor vapor is generated...

Here we report our initial results on the computational fluid dynamics analysis of airflow field generated during the flight of a multicopter. We propose to utilize the airflow field to facilitate gas detection on board the multicopter. When a multicopter is flying, each rotor generates strong airflow in the downward direction. This airflow spreads...

This paper reports on olfactory amplifying systems and reviews related technologies. We have developed two types of olfactory amplifying systems that allow the user to sense smells with amplified sensitivities. In the first system, odor molecules drifting in the air are collected using an adsorbent material. The concentrated odor vapor is generated...

Here we report the results of experiments conducted to see if human subjects can track a faint airborne odor plume with the help of an olfactory assist system that presents the amplified olfactory stimuli to the subjects. The system consists of a gas sensor and an odor generator. The sensor measures the concentration variations of a gaseous chemica...

This paper reports on the development of compact surface plasmon resonance (SPR) sensors for mobile robot olfaction. Underwater robots benefit from olfactory sensing capabilities in various tasks including the search for unexploded ordnance and undersea wreckage. Although the SPR-based chemical sensor is a promising sensing platform, the cumbersome...

This paper reports the development of an odor concentrator for presenting intensified odors to aged people with declined olfactory abilities. The aim of this research is to develop an odor concentrator that can concentrate odor molecules wafting in the air in a short time. In the proposed system, air samples are sucked by using a pump into a flow-t...

Olfactory assist systems that allow the user to sense smells with amplified sensitivities are reported. We have developed two types of systems. The first system, an olfaction augmenter, detects the presence of a volatile organic compound in the air using a gas sensor, and presents an odor with an amplified intensity to the user using an odor genera...

A new gas source localization method that uses actively generated airflow is proposed. A gas source localization robot searches for the location of a gas source by tracking a gas plume in the upwind direction. However, the robot often fails in tracking the plume in an actual environment owing to the large fluctuations of the airflow field and the p...

Here we report on a new method for robotic gas source localization. In the method proposed in this series of work, a mobile robot equipped with gas sensors and an anemometer is used to measure the gas concentration and airflow direction at various locations in the area under consideration. The location of the gas source is estimated by applying a t...

Here we report on a new method for robotic gas source localization. Research efforts are being made to develop mobile robots that can autonomously search for gas sources. The tasks envisaged for such robots include detecting gas leaks in industrial plants and exploring gas emissions in landfill sites. If a mobile robot is provided with gas sensors,...

Mobile robots that can search for gas sources are being developed to accomplish various tasks for protecting people’s safety, e.g., detecting gas leaks in industrial plants. If highly sensitive gas sensors are provided, robots will even be able to search for explosives set by terrorists in airports and find missing persons in disaster sites, just a...

Here we report a portable wind/olfactory display system that can present a virtual airflow and/or odor source at an arbitrary position on a screen of a tablet computer. The system is named a smelling screen mini. As in our original-size smelling screen, airflows generated by four fans are made to impinge on each other, and thus, an airflow directed...

Over the past two decades, various research efforts have been made to employ chemical sensing capabilities on mobile robot platforms. This chapter presents the tasks that mobile robots are expected to accomplish with the help of chemical sensing capabilities with the technical challenges involved in those tasks. Then, it presents hardware setups th...

This paper investigates the effect of active water sampling to enhance chemical reception for small underwater robots. The search for a chemical source in a stagnant water environment is not an easy task because the chemical solution released from the source stays in the close vicinity of the source. No signal is obtained even if a robot with chemi...

Here we report on the development of an olfactory amplifier device that collects airborne odor molecules and presents condensed odors to the user. In the proposed device, gaseous chemicals contained in the air are collected onto an adsorbent. By adding heat to this adsorbent, the chemicals accumulated on its surface are desorbed, and thus, concentr...

Here we report a portable olfactory display system to be used with a tablet computer for interactive odor/airflow presentation. As its predecessor, the system can present a virtual odor and/or airflow source at an arbitrary position on the screen of the tablet computer. In the proposed system, airflows generated by four fans are made to deflect mul...

Here we propose a portable display system for presenting odor and airflow, which is used in combination with a tablet computer. The proposed display system can generate a spatial airflow distribution in front of a touch screen of the tablet computer by using four fans placed at four corners of the screen. Airflows generated by the fans are made to...

This paper reports on our efforts toward automatic estimation of an indoor airflow field for efficient mobile robot gas source localization. Advance knowledge of the entire airflow field is highly helpful for gas source localization. We propose to use a mobile robot equipped with a laser scanner and a thermal camera to measure the geometry of an in...

Here we report on the use of an olfactory assist system to track an airborne odor plume. The system consists of a gas sensor and an odor generator. The sensor measures the concentration variations of a gaseous chemical compound wafting in the air. The odor generator presents the user with an odor with amplified concentration variations. Thus, the u...

Here we propose to use airflow actively generated by using fans to assist a gas-source localization robot. Gas molecules released from their source spread in the environment mainly by being carried by the airflow. A gas-source localization robot searches for the location of the gas source by tracking the airborne gas plume in the upwind direction....

A display system that can present a virtual odor and/or airflow source at an arbitrary position on a computer monitor screen is proposed. Potential applications of this system include multimedia digital signage. In the proposed system, airflows generated by four fans are made to deflect multiple times by making them collide with each other. Finally...

An olfactory display is a device that generates various odors and delivers them to the user's nose. It has been originally developed as part of a multimodal user interface in a virtual reality system to provide a rich experience to the user. Presenting odors together with visual images and sound is also expected to enhance the reality of various sc...

Here we propose a device that can amplify odor intensity by concentrating odorous chemicals contained in air. The device consists of an air pump, an adsorbent, and a heater. Air samples are sucked into the device by using the pump. The gaseous chemical compounds contained in the air samples are trapped on the adsorbent. The concentrated odor vapor...

Gas sensors are used to detect the presence of gaseous chemical species in air. Once the target gas is detected, it is often required to track the gas and locate its source. In principle, the gas source location can be determined by tracking the spatial gas concentration gradient, which can be measured using a spatially aligned array of gas sensors...

Here we propose to employ computational fluid dynamics simulation for mobile robot gas source localization. In a non-ventilated indoor environment, natural convection caused by the temperature distribution in the room is the main force that disperses gas molecules from their source. A mobile robot equipped with a laser scanner and a thermal camera...

This paper reports on a new display system that can present a virtual odor and/or heat source at an arbitrary position on a two-dimensional screen. By releasing a smell of coffee in a warm airflow while showing a cupful of coffee on an LCD monitor, for example, the system can make the user feel as if warm savory steam is emanating from the coffee....

In this paper, an olfaction aid system is proposed, which allows a human worker to have an enhanced sense of smell when searching for a gas/odor source. The system consists of a gas sensor and an odor generator. It measures the concentration variations of odorous chemical compounds that the user is being exposed to, and presents an odor with amplif...

We propose a new olfactory display system that can generate an odor distribution on a two-dimensional display screen. The proposed system has four fans on the four corners of the screen. The airflows that are generated by these fans collide multiple times to create an airflow that is directed towards the user from a certain position on the screen....

Crayfish are known to generate water jets by waving their special appendages with a fan-like shape. The generated jets entrain surrounding water, and thus inflow converging toward their olfactory organs is induced. Therefore, the jets are considered to help crayfish collect water samples to search for the smell of a prey. Although crayfish are also...

The smelling screen is a new olfactory display that can generate a localized odor distribution on a two-dimensional display screen. The generated odor distribution is as if an odor source had been placed on the screen, and leads the user to perceive the odor as emanating from a specific region of the screen. The position of this virtual odor source...

Robots are generally equipped with at least several different modalities of sensors. Vision and range sensors are the most popular, especially in mobile robots. On the other hand, olfaction (or chemical sensing in general) had long been ignored in the robotics community because of the technical difficulties involved in realizing artificial olfactio...

A new device for determining the direction of a gas source is proposed. Peltier elements are used to transfer heat from the center of the device to its left and right sides. Ascending air currents generated from the warmed sides of the device bring a gaseous chemical substance trailing along the floor toward the right and left gas sensors. A descen...

A new olfactory display system that can generate odor distribution along a two-dimensional screen is reported. In the proposed system, airflows generated by four fans are made to deflect multiple times by making them collide with each other. Thus, an airflow directed toward the user from a certain position on the screen is generated. By introducing...

In this paper, we propose a new device for determining a direction of a gas source using thermal air currents generated by Peltier elements. The use of thermal convective flow is advantageous in gas sensing. For example, a gaseous chemical substance trailing along the floor can be collected toward a gas sensor placed at an elevated height using the...

In this paper, a display system that can present a virtual airflow and/or odor source on a screen is proposed. The system can give the user a sensation that airflow and/or odor is coming from a certain position on a computer screen. Four fans are used in the proposed display and are placed at the four corners of the screen. Airflows generated by th...

A localization method based on klinotaxis is proposed to contribute to improve the environment of lakes using the underwater robot that imitates fish. By using the method, the source can be found from the change of stimulation during wave propulsion in a dispersion field. An experiment is performed using a mechanism of sniffing to explore the relat...

A new olfactory display that can present a virtual odor source at an arbitrary position on a two-dimensional screen is proposed in this paper. The proposed device can give a sensation that an odor is emanating from a certain position on the screen. Fans are placed at the four corners of the screen. The airflows generated by the fans are deflected m...

In this chapter, the authors describe fluid dynamics considerations regarding odor dispersal in real environments and their relationship with realistic odor presentation using an olfactory display. The authors propose the use of a Computational Fluid Dynamics (CFD) simulation in conjunction with the olfactory display. A CFD solver is employed to ca...

Here we report the results of our investigations on designing an amperometric electrochemical sensor probe with multiple disk working electrodes. The sensor can not only detect a chemical substance dissolved in water but also can determine the direction of its flow by using the shielding effect that appears between closely arranged working electrod...

In this study, a new robotic system equipped with an active stereo nose (ASNose) is proposed to localize a gas source. ASNose is equipped with two suction pumps and two gas sensors, and determines the direction of the gas source by comparing the left and right sensor responses to the sucked air samples. In the proposed mobile robot, ASNose is mount...

Mobile robots equipped with gas sensors have been applied to measure gas distributions in given areas. Here we present experimental results to show that the obtained distributions are, at least in some cases, distorted because of upward air currents created by self-generated heat of the robot. The results of CFD simulations show that human olfactio...

An autonomous robot and an odor compass could help find the source of a leak

A new device has been developed for generating airflow field and odor-concentration distribution in a real environment for presenting to the user. This device is called a multi-sensorial field (MSF) display. When two fans are placed facing each other, the airflows generated by them collide with each other and are radially deflected on a plane perpe...

A new method of detecting the flow direction of an aqueous solution of a chemical substance is proposed. The detection mechanism is based on the shielding effect that appears between multiple working electrodes of an amperometric electrochemical sensor. When the sensor is exposed to the flow of a chemical solution, a smaller response current is obt...

Olfaction is now becoming available in Multiple Sensorial Media because of recent progress of an olfactory display. One of the important functions of the olfactory display is to blend multiple of odor components to create a variety of odors. We have developed the olfactory display to blend up to 32 odor components using solenoid valves. High -speed...

A new gas sensing system is proposed, which uses an actively generated air curtain to determine the direction of a gas source. The system is equipped with two gas sensors and two pumps. Air is sucked through two intake pipes, and is delivered to the left and right gas sensors to make lateral comparison of the gas concentration. The exhaust of the p...

In this paper, we present our initial experiments to collect a database for studying mobile robot olfaction. Mobile robots with olfactory sensing capabilities are expected to be used in various applications including gas distribution mapping and gas source localization. Owing to the turbulent nature of the airflow field and the gas distribution, th...

This article reports on an underwater robot that searches for chemical sources in stagnant water. Biological studies suggest that crayfish in search of foods generate water currents by using their fan organs (maxillipeds). The proposed robot is equipped with two pairs of fanning arms mimicking crayfish maxillipeds. The chemical substance staying ne...

In this paper, a system for interactive odor presentation based on computational fluid dynamics (CFD) simulation is described. The devices to present olfactory stimuli are called olfactory displays. To provide high-presence olfactory stimuli, a model of the virtual environment shown on the computer screen is provided to a CFD solver. The airflow fi...

This article describes the investigations on the effect of airflow on the perception of odors presented by an olfactory display device. A clear sensation of the direction to an odor source can be given to the user of the olfactory display when the air currents are provided to the user's face by using fans. When the air currents are not provided, th...

This paper reports on an olfactory display system that enables the synchronized presentation of odors with airflow in a virtual reality environment. In the proposed system, computational fluid dynamics simulation is conducted to calculate how an odor released from its source is spread in a given airflow field. An odor vapor with an appropriate conc...

In this paper, we present our initial experiments to collect a database for studying mobile robot olfaction. Mobile robots with olfactory sensing capabilities are expected to be used in various applications including gas distribution mapping and gas source localization. Owing to the turbulent nature of the airflow field and the gas distribution, th...

This paper investigates the applicability of a gas-source localization method in outdoor environment. In the proposed method, a mobile robot is used to scan the area under consideration and to collect data on gas concentration and airflow velocity at various locations. The location of the gas source is estimated by applying a turbulent diffusion mo...

We present a mechanical design and implementation of spherical ultrasonic motor (SUSM) that is an actuator with multiple rotational degrees of freedom (multi-DOF). The motor is constructed of 3 annular stators and a spherical rotor and is much smaller and simpler than conventional multi-DOF mechanisms such as gimbals using servomotors. We designed...

This paper reports on the improvements of an autonomous wheeled underwater robot designed to localize chemical sources in stagnant water. The robot can generate water currents by waving its arms mimicking fan organs of crayfish (maxillipeds). Generated water currents help the robot detect chemical substances by drawing water samples from the surrou...

This paper reports on an underwater wheeled robot designed to locate chemical sources by mimicking the behavior of a crayfish in still water. Crayfish in search of food generate water currents by waving their fan organs, i.e., the maxillipeds, to collect the food odors from the surroundings to the chemoreceptor organs. Similarly, the robot waves th...

Mobile robots equipped with gas sensors can be used for automated measurement tasks including odor trail following, gas source localization, and gas distribution mapping. This article reports on the development of a blimp robot for mapping three‐dimensional gas distribution in indoor environments. The blimp robot is programmed to fly randomly so th...

This article describes the experiments on an interactive application of an olfactory display system into which computational fluid dynamics (CFD) simulation is incorporated. In the proposed system, the olfactory display is used to add special effects to movies and virtual reality systems by releasing odors relevant to the scenes shown on the comput...

The results of our current multidisciplinary research efforts on the development of an olfactory display system are demonstrated. To present odors with a vivid sense of reality, we propose to use computational fluid dynamics (CFD) simulation in conjunction with the olfactory display system. In this demonstration, an odor is released with a movie cl...

An active stereo nose (ASNose) is proposed for localization of gas sources. Dogs actively deform their nostrils when they sniff. The air in front of a dog is drawn to the nose by inhalation, and then, ejected backward. This backward jet further induces air currents flowing from the front of the dog to the nose, which assist in collecting odors. To...

This paper describes some fluid dynamic considerations for attaining realistic odor presentation using an olfactory display. Molecular diffusion is an extremely slow process and, therefore, odor molecules released from their source are spread by being carried off by airflow. Since the flow we encounter is almost always turbulent, the intensities of...

An olfactory display is a device that delivers various odors to the user's nose. It can be used to add special effects to movies and games by releasing odors relevant to the scenes shown on the screen. In order to provide high-presence olfactory stimuli to the users, the display must be able to generate realistic odors with appropriate concentratio...

In this paper we present initial experiments towards environmental monitoring with a mobile platform. A prototype of a pollution monitoring robot was set up which measures the gas distribution using an ldquoelectronic noserdquo and provides three dimensional wind measurements using an ultrasonic anemometer. We describe the design of the robot and t...

An active stereo nose (ASNose) is proposed to develop a robot dog for gas source localization. Dogs are known to actively deform their nostrils when they sniff. The air samples in front of a dog are drawn to the nose by inspiring air. In the expiration phase of sniffing, air is ejected backward. This backward jet induces air currents flowing from t...

This paper describes an underwater wheeled robot designed to search for a chemical source under stagnant flow conditions. In the absence of the flow, the released chemical stays in the immediate vicinity of the source. Therefore, no chemical is detected even if the robot is only a few centimeters away from the source. Crayfish in search for food ar...

This paper reports on the development of an autonomous wheeled underwater robot designed to localize chemical sources under stagnant flow conditions. Crayfish in search of food generate water currents using their fan organs, i.e., exopodites of maxillipeds. The generated currents help in collecting odors from the surroundings to their chemosensory...