.............................................................................................................................................................. 6 1 Introduction ............................................................................................................................................. 7 1.1 Motivation .......................................................................................................................................................... 7 1.2 Previous Surveys ............................................................................................................................................. 8 1.3 Overview of Technologies ........................................................................................................................... 9 1.4 Indoor Positioning Applications ............................................................................................................ 11 1.5 Structure of this Work ............................................................................................................................... 14 2 User Requirements ............................................................................................................................. 15 2.1 Requirements Parameters Overview .................................................................................................. 15 2.2 Positioning Requirements Parameters Definition ......................................................................... 17 2.3 Man Machine Interface Requirements ................................................................................................ 19 2.4 Security and Privacy Requirements ..................................................................................................... 20 2.5 Costs .................................................................................................................................................................. 20 2.6 Generic Derivation of User Requirements......................................................................................... 20 2.7 Requirements for Selected Indoor Applications ............................................................................. 21 3 Definition of Terms ............................................................................................................................. 25 3.1 Disambiguation of Terms for Positioning .......................................................................................... 25 3.2 Definition of Technical Terms ................................................................................................................ 27 3.3 The Basic Measuring Principles ............................................................................................................. 29 3.4 Positioning Methods ................................................................................................................................... 31 4 Cameras .................................................................................................................................................. 34 4.1 Reference from 3D Building Models .................................................................................................... 35 4.2 Reference from Images .............................................................................................................................. 36 4.3 Reference from Deployed Coded Targets .......................................................................................... 37 4.4 Reference from Projected Targets ........................................................................................................ 38 4.5 Systems without Reference ..................................................................................................................... 39 4.6 Reference from Other Sensors ............................................................................................................... 40 4.7 Summary on Camera Based Indoor Positioning Systems ........................................................... 40 5 Infrared ................................................................................................................................................... 42 5.1 Active Beacons .............................................................................................................................................. 42 5.2 Imaging of Natural Infrared Radiation ............................................................................................... 43 5.3 Imaging of Artificial Infrared Light ....................................................................................................... 43 5.4 Summary on Infrared Indoor Positioning Systems ....................................................................... 44

Indoor Positioning Technologies

This paper aims to provide the reader with a review of the main technologies explored in the literature to solve the indoor localization issue. Furthermore, some systems that use these enabling technologies in real-world scenarios are presented and discussed. This could deliver a better understanding of the state-of-the-art and motivate new research efforts in this promising field. Finally, focusing on one of the major challenges in the indoor localization field, i.e., the indoor animal tracking, existing indoor tracking systems have been reviewed and compared by analyzing advantages and drawbacks.

A survey on indoor positioning systems

Rfid Technology Integration for Business Performance Improvement

This paper presents an assistance equipment of human elbow joint, which aims to help patients who have elbow injury issues in smart campus environment A new type of soft pneumatic elbow pad (SPEP) which adopted soft material manufacturing technology is presented Compared with the rigid assistant equipment, the SPEP shows more comfort, smaller equipment size, and convenience of wearing Meanwhile, three different types of sensors (the air pressure sensor, bending sensor, and force sensor) are used in the SPEP to discover the two important characteristics which are applied In order to verify the effectiveness of the designed SPEP, two analysis methods are presented The surface electromyogram signal and the root mean square analysis are used in the first method, which prove that the SPEP could reduce the activity of the muscle and assist power during the elbow movement Compared with the first method, the second method which is the model of calculation after wearing SPEP can obtain specific value of assisting power in the biceps and olecranon Thus, the aforementioned methods illustrate the feasibility of the SPEP Finally, in order to make the SPEP used in daily life, a portable backpack with the control system and the energy system is applied to the field of human assistance equipment

A New Soft Pneumatic Elbow Pad for Joint Assistance With Application to Smart Campus

This paper describes the development of an angle-sensorless exoskeleton with a tap water-driven artificial muscle actuator. The artificial muscle actuator consisted of an elastic rubber tube reinforced by braided fiber. Such actuators are highly flexible, lightweight, and water-resistant, and thus are inherently safe even for operations in direct contact with humans. An estimation system for the displacement of the artificial muscle actuator based on the water flow rates detected by flowmeters was constructed for the water-hydraulic exoskeleton. In addition, estimators of the velocity and acceleration of the actuator based on the estimated displacement and the measured flow rates were derived and incorporated into the estimation system. With this system, our previous wearable upper-limb assistive exoskeleton prototype was converted into an angle-sensorless version with higher safety in wet conditions. Its assistive performance was evaluated through experiments with research participants. Experimental results demonstrated that muscle activity could be reduced, although an assistive control strategy was executed with the variables estimated, excluding force.

A Water-Hydraulic Upper-Limb Assistive Exoskeleton System with Displacement Estimation

We propose an Infrared-Ray (IR) type azimuth sensor system for use in indoor environments. The feature of this sensor is an adequate conic-shaped linear polarizer film. Because of the drift in the sensor, azimuth information provided by the angular velocity sensor (gyroscope) is unreliable. It is not currently possible, in virtually any indoor environment like an office or factory, to use geomagnetism to detect the existence of iron-based furniture or reinforced concrete. Our sensor system can recognize a position measured from the non-drift azimuth information based on the installation of only one landmark. We created a prototype of the sensor based on this concept and discuss the sensing properties, as indicated by experimental results.

Indoor IR azimuth sensor using a linear polarizer

Wearable robotic assist devices need to be safe for the user. Pneumatic actuators are suitable for driving those devices because they are highly safe for humans. However, the responsiveness of pneumatic actuators is lower than that of electric actuators. In this paper, we propose an approach to muscle-burst onset detection by monitoring surface electromyogram (EMG) signals, and utilize it to trigger the actuator of a pneumatic power-assist device for the human arm. Experimental verification demonstrates the validity of our approach for detecting muscle-burst onset by EMG signals online, and the applicability of the EMG trigger for the pneumatic power-assist device.

A pneumatic arm power-assist system prototype with EMG-based muscle activity detection

Robotic technologies for supporting human activities have received much attention in recent years. The purpose of this study is to develop a wearable power assist device with a water-hydraulic artificial muscle actuator. This power assist device aims at helping wearer’s elbow-joint movement. Since our power assist device is directly driven by tap water, it does not require pumps or compressors. Therefore, it needs much lower electric power than typical pneumatic and electric actuators. An artificial muscle actuator is used to actuate the power assist device because artificial muscle actuators are lightweight and highly flexible and would not hurt a person even in a collision, as this type of actuator consists of a flexible rubber tube surrounded by a braided-fiber shell. The control system of the power assist device comprises impedance control and amplification control. The impedance control is able to adjust the characteristics of dynamic interaction between the power assist device and a wearer, i.e. inertia, damping, and stiffness. The amplification control enables the power assist device to enhance torque exerted by a wearer. The power assist device developed in this study was worn by subjects and its effectiveness was examined based on surface electromyogram signals which reflect muscle activity. Experimental results demonstrated that our water-hydraulic power assist device leads to a decrease of muscle activity for all the subjects.

https://www.jstage.jst.go.jp/article/transjsme/82/841/82_16-00174/_pdf

Development of an elbow power assist device with a water-hydraulic muscle actuator

(1) Background: A mouth-free interface is required for functional electrical stimulation (FES) in people with spinal cord injuries. We developed a novel system for clenching the human metacarpophalangeal (MP) joint using an earphone-type ear canal movement sensor. Experiments to control joint angle and joint stiffness were performed using the developed system. (2) Methods: The proposed FES used an equilibrium point control signal and stiffness control signal: electrical agonist–antagonist ratio and electrical agonist–antagonist sum. An angle sensor was used to acquire the joint angle, and system identification was utilized to measure joint stiffness using the external force of a robot arm. Each experiment included six and five subjects, respectively. (3) Results: While the joint angle could be controlled well by clenching with some hysteresis and delay in three subjects, it could not be controlled relatively well after hyperextension in the other subjects, which revealed a calibration problem and a change in the characteristics of the human MP joint caused by hyperextension. The joint stiffness increased with the clenching amplitude in five subjects. In addition, the results indicated that viscosity can be controlled. (4) Conclusions: The developed system can control joint angle and stiffness. In future research, we will develop a method to show that this system can control the equilibrium point and stiffness simultaneously.

/pdf/earable-o-omega-a-novel-clenching-interface-using-ear-canal-1811qc0x.pdf

Earable Ω (OMEGA): A Novel Clenching Interface Using Ear Canal Sensing for Human Metacarpophalangeal Joint Control by Functional Electrical Stimulation

In recent years, wearable interfaces have attracted research attention. As wearing masks has become common worldwide after the appearance of the coronavirus disease 2019, we devised a system to measure facial information from a mask, focusing on facial expressions in this study. Specifically, the expansion and contraction of the mask was measured to classify facial expressions. We conducted classification experiments under various conditions, achieving high classification accuracy, especially for facial expressions in the non-woven fabric mask to which a conductive thread was attached. We found that conductive threads are affordable and easy to sew into masks, and they can be used to construct a wearable interface. 

Keita Atsuumi

Papers

Indoor IR azimuth sensor using a linear polarizer

A pneumatic arm power-assist system prototype with EMG-based muscle activity detection

Development of an elbow power assist device with a water-hydraulic muscle actuator

Earable Ω (OMEGA): A Novel Clenching Interface Using Ear Canal Sensing for Human Metacarpophalangeal Joint Control by Functional Electrical Stimulation

A Facial Expression Discrimination System Using the Expansion and Contraction of Face Masks and the Conductive Thread