User Height Research Articles

Design of a Digital Height and Weight Measuring Instrument Using Ultrasonic Sensors and Weight Sensors Based on Arduino Uno

Digital height and weight measuring devices are important tools in monitoring individual health. In this study, we propose the design of a height and weight measuring instrument that uses an ultrasonic sensor and a weight sensor based on Arduino Uno. Ultrasonic sensors are used to measure body height by sending ultrasonic waves towards the user and then detecting the time required for the waves to return to the sensor after being reflected by the surface above the user's head. Using simple trigonometry principles, the user's height can be calculated accurately. Meanwhile, a weight sensor is used to measure body weight. The user's weight is placed on a platform equipped with a weight sensor. The data generated by the sensor is then processed by Arduino Uno to calculate body weight with precision. The height and weight measurement data is displayed digitally on the LCD screen installed on the tool. In addition, this tool is also equipped with the ability to save measurement data so that users can track changes in their height and weight over time. Testing is carried out to verify the accuracy and reliability of the tool. Test results show that this tool is able to measure height and weight with a high level of accuracy. Thus, this tool can be an effective and efficient solution for monitoring personal health.

A Study on Adjustable Height Stand for Temperature Scanner

This research project aimed to transform a common temperature scanner stand into a user-friendly adjustable stand holder temperature scanner. The temperature scanner automatically adjusts its height according to the user's height, reducing the risk of contact infection by using an ultrasonic sensor to detect the user in front of the scanner. The experiment involved measuring the time taken for the thermometer to move from the starting position to the maximum height of different individuals with varying heights. A frame capture application on a smartphone was used to record the motion and time, capturing data at a rate of 33 frames per second for accuracy. The tests were conducted using a constant motor speed of 100 revolutions per minute. The results showed that the duration of waiting time for the adjustable stand holder temperature scanner was valid for individuals with heights ranging from 100 cm to 180 cm. The constructed adjustable stand successfully served its purpose and demonstrated functionality and reliability in real-life testing. To improve the accuracy and expand the capabilities of the adjustable stand holder temperature scanner, future work are needed such as utilizing smart system programs to cater to user preferences, implementing material modifications to reduce vibrations, and introducing additional features to indicate a person's height and weight.

Noise segmentation for step detection and distance estimation using smartphone sensor data

As for the low-cost and accuracy benefits of integrating Artificial Intelligence (AI) technologies in smartphones, the embedded smart sensors have been utilized in indoor localization and distance estimation applications rather than the requirement of wearable sensors. However, the effect of a potential noise during the user’s movement is still an issue, i.e. irrelevant movements. Knowing that the noise can severely impair the accuracy of distance estimation by increasing or decreasing the number of estimated steps. Therefore, this paper proposes a distance estimation method based on dynamic step size and shape. It aims at removing the noise from the bit signal and detecting the number of steps regardless of the noise using the magnitude value for the three-axis accelerometer data. Furthermore, it involves the variables of the user's height with relation to the step size to estimate the walking distance. The experiment sets allow four phases including data collection and filtering, peak detection, dynamic step size detection, and distance estimation. The low-pass filter is applied to remove the resultant noise of irrelevant movements such as handshaking, texting, swinging, etc. The experimental results showed that the proposed method of step detection, step size, and walking distance estimations achieved significant accuracy improvement over existing current approaches reaches (98%) when a pedestrian was walking in multiple mode changes.

Design of Digital Height Measurement Based Microcontroller AT89C51

Height measuring instrument is a tool that can be used by humans to assist in the process of determining height. Most height gauges in use today are analog or manual height gauges. In today's technological developments, the author will make an automatic height measuring device using ultrasonic sensors to calculate data from received objects. The sensor is used to measure the working distance at a frequency of 40 KHz so as not to interfere with human hearing. As the control center of this measuring instrument, it uses the Arduino Uno Microcontroller. This measuring instrument is capable of measuring an object with the accuracy of the sensor reading the data, namely the maximum height of 195 cm and the minimum height of 50 cm. The advantage of this tool is that it uses a microcontroller and sensor technology, while to display measurement results using an LCD and LCD measuring instruments can move according to the height of the object, to move the LCD a DC motor is used as the driver. And the measurement results are issued through the speaker in the form of sound that has been stored on the SD Card in WAV format, making it easier for blind people to know the user's height. The drawback of this tool is the construction of the tool and sensor readings, so that the results obtained from the measurements still contain some errors.

Statistical Characterization of GNSS Signal-in- Space Ranging Errors for the User Within and Beyond Space Service Volume

The number and scope of space applications of global navigation satellite systems have grown significantly. However, the availability and the navigation performance for a spacecraft operating within and beyond the space services volume are different from those of terrestrial service volume users. To effectively evaluate the space service performance of navigation satellite systems, we present the calculation method of signal-in-space ranging error for space users. Considering the geometric visibility and the constraints of the lowest carrier-to-noise ratio, we analyze the feasibility of receiving the signal transmitted from the different off-nadir angles and obtain the coverage area of navigation satellite. Then, the relationship between the weighting factors of ephemeris errors and the orbital height of the user spacecraft is analyzed. Finally, the statistics characteristic of signal-in-space ranging error of typical navigation satellites is presented. The results show that the signal-in-space ranging error increases first and then decreases as the orbital height of the user increases. Generally, when the user's orbital height is slightly higher than the orbital height of the navigation satellite, the signal-in-space ranging error reaches a maximum. In particular, due to the significant horizontal orbit error, global signal-in-space ranging error of the Beidou geostationary orbits satellites increase significantly compared with the user located on the ground. Therefore, the impact of user height changes on the statistical properties of signal-in-space ranging error cannot be ignored when evaluating the navigation performance of the space user.

Rehabilitation motion recognition based on the international biomechanical standards

Since 1990, the International Society of Biomechanics (ISB) has made efforts to provide uniformity to motion description. However, the majority of user studies and technological systems that use motion recognition for rehabilitation, such as virtual and augmented reality (VR and AR), do not follows this standard. Typically, VR and AR techniques recognize motion by comparing human joint positions to a pre-recorded movement, direction, or position relative to an interactive object. Aiming to fill a lack of biomechanical reference on joint motion recognition and analysis for rehabilitation interactive systems, this paper proposes a movement description and recognition method following the ISB standard. The developed method aims to provide computational solutions which are clinically relevant and that uses clinical jargon known to the rehabilitation therapists. The proposed method will also allow motion analysis independent of user's height or its position relative to sensor. We conclude this paper by presenting a comparative analysis of the effectiveness of the Kinect sensors (versions 1 & 2) regarding the recognition of patient exercise motions related to the biomechanical standard. Our solution consists of biomechanical motion classification by identifying in which 3D plane the motion occurs. The motion recognition solution also provides patient posture, motion, and information about incorrect exercise performance. The method was developed by first implementing a body representation and Joint Coordinate System based on ISB standard and then motion angle and biomechanical classifications were performed. Specific methods to measure axial rotations were developed inspired by the traditional goniometry strategy. Also, experiments to evaluate if the method is able to classify the biomechanical motions and, thus, detect whether or not they are being performed correctly were performed using both Kinect v1 and Kinect v2. Motions were performed in correctly and wrongly to also verify false positives. Each classified motion was performed 100 times: 70 correct repetitions (35 at normal speed and 35 fast ones) and 30 wrong ones (out of their respective plane). The motion recognition method showed good efficacy in classifying the biomechanical motions correctly. Most of motions presented great success rate of recognition . higher than 80%, mainly using a 20 degrees tolerance.

PEMODELAN APLIKASI MOBILE MODUL PERKULIAHAN BERBASIS CLIENT SERVER

The faster technological development makes it easier for us to carry out life activities more easily. currently mobile applications have not been used so much in a lecture that an application is needed that can meet these shortcomings. For that I try to model a mobile application that can help lecturers and students in sharing learning material at each meeting so as to facilitate the process of a lecture. Which is based on client server where this application can change its data at any time according to the user's height and will be modeled using the Unifield Modeling Language (UML) tool.

An assistive lower limb exoskeleton for people with neurological gait disorders.

Lower limb exoskeletons have already proven the capability to give back mobility to people suffering from spinal cord injury (SCI). Other important populations such as people with multiple sclerosis or muscular dystrophy, frail elderly and stroke victims, suffer from severe gait impairments and could benefit from similar technology. The work presented in the current paper describes a novel design of a 6-actuated degrees of freedom (DOFs) assistive lower limb exoskeleton for people with moderate mobility impairments. The electrical actuators are all remotely located on the back of the user for a more compact design with high dynamics. Cable driven solutions are used to transmit the flexion/extension of the hip and knee joints, while a powerful ballscrew carries out the hip adduction/abduction. The design of this exoskeleton, named AUTONOMYO, follows the key specifications of being highly back-drivable and able to perform dynamic motions at low energy consumption. AUTONOMYO is capable to assist the user's balance by providing complementary torques at the hip and the knee. Results show that the projected level of assistance for sit-to-stand transition varies from 50% to 100% in function of the user's bodyweight and height while higher level of assistance are reached for walking and stairs climbing activities.

Kinesthetic Force Feedback and Belt Control for the Treadport Locomotion Interface.

This paper describes an improved control system for the Treadport immersive locomotion interface, with results that generalize to any treadmill that utilizes an actuated tether to enable self-selected walking speed. A new belt controller is implemented to regulate the user's position; when combined with the user's own volition, this controller also enables the user to naturally self-select their walking speed as they would when walking over ground. A new kinesthetic-force-feedback controller is designed for the tether that applies forces to the user's torso. This new controller is derived based on maintaining the user's sense of balance during belt acceleration, rather than by rendering an inertial force as was done in our prior work. Based on the results of a human-subjects study, the improvements in both controllers significantly contribute to an improved perception of realistic walking on the Treadport. The improved control system uses intuitive dynamic-system and anatomical parameters and requires no ad hoc gain tuning. The control system simply requires three measurements to be made for a given user: the user's mass, the user's height, and the height of the tether attachment point on the user's torso.

Real-time dangling objects sensing: A preliminary design of mobile headset ancillary device for visual impaired.

Blinds and severe visual impairments can utilize tactile sticks to assist their walking. However, they cannot fully understand the dangling objects in front of their walking routes. This research proposed a mobile real-time dangling objects sensing (RDOS) prototype, which is located on the cap to sense any front barrier. This device utilized cheap ultrasonic sensor to act as another complement eye for blinds to understand the front dangling objects. Meanwhile, the RDOS device can dynamically adjust the sensor's front angle that is depended on the user's body height and promote the sensing accuracy. Meanwhile, two major required algorithms, height-angle measurement and ultrasonic sensor alignment, are proposed with this prototype. The research team also integrated the RDOS device prototype with mobile Android devices by communicating with Bluetooth to record the walking route.

Step length estimation using handheld inertial sensors.

In this paper a novel step length model using a handheld Micro Electrical Mechanical System (MEMS) is presented. It combines the user's step frequency and height with a set of three parameters for estimating step length. The model has been developed and trained using 12 different subjects: six men and six women. For reliable estimation of the step frequency with a handheld device, the frequency content of the handheld sensor's signal is extracted by applying the Short Time Fourier Transform (STFT) independently from the step detection process. The relationship between step and hand frequencies is analyzed for different hand's motions and sensor carrying modes. For this purpose, the frequency content of synchronized signals collected with two sensors placed in the hand and on the foot of a pedestrian has been extracted. Performance of the proposed step length model is assessed with several field tests involving 10 test subjects different from the above 12. The percentages of error over the travelled distance using universal parameters and a set of parameters calibrated for each subject are compared. The fitted solutions show an error between 2.5 and 5% of the travelled distance, which is comparable with that achieved by models proposed in the literature for body fixed sensors only.

Toward accessible self-service kiosks through intelligent user interfaces

Public self-service kiosks provide key services such as ticket sales, airport check-in and general information. Such kiosks must be universally designed to be used by society at large, irrespective of the individual users' physical and cognitive abilities, level of education and familiarity with the system. The noble goal of universal accessibility is hard to achieve. This study reports experiences with a universally designed kiosk prototype based on a multimodal intelligent user interface that adapts to the user's physical characteristics. The user interacts with the system via a tall rectangular touch-sensitive display where the interaction area is adjusted to fit the user's height. A digital camera is used to measure the user's approximate reading distance from the display such that the text size can be adjusted accordingly. The user's touch target accuracy is measured, and the target sizes are increased for users with motor difficulties. A Byzantine visualization technique is employed to exploit unused and unreachable screen real estate to provide the user with additional visual cues. The techniques explored in this study have potential for most public self-service kiosks.

Body height-workstation settings matrix: A practical tool for ergonomic VDT workstation adjustment

This paper discusses the development of a body height-workstation settings (BH-WS) matrix for a quick and convenient ergonomic visual display terminal (VDT) workstation adjustment. The matrix is intended to be a practical tool to help VDT users adjust their workstations in order to obtain a proper seated posture. The BH-WS matrix uses two parameters, the user's body height and sex, to estimate recommended workstation settings (in numerals) based on ergonomics principles. Three estimation processes have been used. Firstly, relevant body member measurements are estimated from the body height. Then, both x- and y-coordinates of key body reference points are calculated. Finally, the coordinates of the VDT workstation's reference points are determined to match with those of the body reference points. The recommended settings are then derived from these reference points.

Analysis of ocular surface area for comfortable VDT workstation layout

This paper proposes a comfortable visual display terminal (VDT) workstation layout based on an analysis of ocular surface area (OSA). A large OSA induces eye irritation and eye fatigue because the eye surface is highly sensitive to various stimuli. The authors considered that OSA must be one of the useful indices of visual ergonomics and applied it to evaluate VDT workstation layout. Each subject was asked to perform a word processing task using four different VDT workstation layouts. It was found that the main factor affecting OSA was not cathode ray tube (CRT) height itself but the distance between the CRT and keyboard. Thus the following workstation layout is recommended to realize comfortable VDT operation: (1) the desk height should be adjusted to the user's height; and (2) the CRT display should be set closer to the keyboard to provide a smaller OSA.

An inexpensive, simple device for viewing stereoscopic films.

Stereoscopic x-ray viewers commercially available in the United States are generally of two types: (a) units that produce excellent stereoscopic images but are expensive, bulky, relatively immobile, and require several square feet of floor space (e.g., Stanford Pedestal Model Stereoscope, $529.00); (b) compact and light-weight hand-held models that produce good images only if held perfectly still, a difficult thing to do (General Electric Hand Stereoscope, $55.00). The viewer described in this communication is light and compact and can easily be fabricated in a small workshop at a cost of under $15.00 for materials. Stereoscopic images are as good as those obtained with the expensive units since this viewer is not hand-held but is rigidly attached to existing conventional viewboxes. The viewer consists of a 3 × 4-inch front surface mirror glued to a Lucite sheet of the same size which is attached to the bottom of a vertical tube by a universal joint. The top of the tube is attached to one end of a horizontal bar having two strong horseshoe magnets bolted to the other end. The horizontal bar is adjustable in length, and the tube, by sliding on the bar, is adjustable in height (Fig. 1). In use, the viewer is magnetically attached to the top of a steel viewbox in a position so that the horizontal bar projects from the front of the box and perpendicularly to the face (Fig. 2). If the box is of nonmagnetic material, one can first attach a sheet of steel to the top or use strong suction cups in place of the magnets. With the stereo shift running horizontally, a pair of films is placed on the viewbox on either side of the bar. The position of the right film is horizontally reversed in relation to the left film since it will be viewed as a mirror reflection. The user places the mirror along the right side of his nose; with both eyes open he looks toward the left film and sees the right film as a reflection in the mirror. Rotating and, if necessary, angling the mirror to superimpose the right image on the left produce the stereoscopic effect. The function of the mirror is in limiting the sight of each eye to its respective film. The smaller the films, the closer they should be viewed. Therefore, the bar length adjusts from about 22 inches for an 8 × 10-inch film to 28 inches for a 14 × 17-inch film. Ideally, the vertical tube should be set so that the mirror is halfway between the upper and lower edges of the films. However, because of the user's height, this setting may be uncomfortable. If the mirror is instead set at eye level, even if it is off center in relation to the films, there is no significant loss of image quality. The placement of a single mirror alongside the nose for viewing stereoscopic films was described by E. S. Kerekes (1), but that mirror was hand-held.