Motion Energy Research Articles

Tracking motion kinematics and tremor with intrinsic oscillatory property of instrumental mechanics.

Tracking kinematic details of motor behaviors is a foundation to study the neuronal mechanism and biology of motor control. However, most of the physiological motor behaviors and movement disorders, such as gait, balance, tremor, dystonia, and myoclonus, are highly dependent on the overall momentum of the whole-body movements. Therefore, tracking the targeted movement and overall momentum simultaneously is critical for motor control research, but it remains an unmet need. Here, we introduce the intrinsic oscillatory property (IOP), a fundamental mechanical principle of physics, as a method for motion tracking in a force plate. The overall kinetic energy of animal motions can be transformed into the oscillatory amplitudes at the designed IOP frequency of the force plate, while the target movement has its own frequency features and can be tracked simultaneously. Using action tremor as an example, we reported that force plate-based IOP approach has superior performance and reliability in detecting both tremor severity and tremor frequency, showing a lower level of coefficient of variation (CV) compared with video- and accelerometer-based motion tracking methods and their combination. Under the locomotor suppression effect of medications, therapeutic effects on tremor severity can still be quantified by dynamically adjusting the overall locomotor activity detected by IOP. We further validated IOP method in optogenetic-induced movements and natural movements, confirming that IOP can represent the intensity of general rhythmic and nonrhythmic movements, thus it can be generalized as a common approach to study kinematics.

New blind navigation sensor based on triboelectrification and electrostatic induction

Triboelectric Nanogenerators (TENGs) have recently gotten a lot of attention in the realm of human mobility. Wearable TENGs can currently be employed for human motion detection and energy harvesting, as is shown by recent studies. However, the majority of these TENGs are used in direct contact with the human body, posing a great challenge for TENGs materials in terms of comfort, breathability, wear resistance, and flexibility. This manuscript presents a novel form of non-contact motion monitoring sensor, which has been designed based on triboelectrification and electrostatic induction. As the designed sensor requires only copper and PTFE materials, it reduces the manufacturing costs. The sensor does not need to be in direct contact with the person to sense the person’s approach and distance. The working principle and other factors influencing the functioning of non-contact TENGs are also investigated. This sensor can effectively detect signals within two meters, with the current signal reaching a value of 57 nA at a distance of 20 cm. More crucially, the sensor’s distance resolution can be accurate up to 1 cm, which is critical for sensing the human body’s approach and distance. Based on this, a simple-to-manufacture, highly sensitive, and easy-to-use intelligent navigation sensor for blind navigation is designed, which can assist blind people in avoiding obstacles effectively. This simple, easy-to-prepare, and efficient TENG and sensing system shows up-and-coming prospects in motion sensing and hazard warning applications.

Correlation between Ion Transport and Structural Heterogeneity in Triazole-Based Polymerized Ionic Liquids

In this study, the relationship between chemical structure, nanoscale organization, and ion transport in 1,2,3-triazolium polymerized ionic liquids (PILs) was investigated by wide-angle X-ray scattering (WAXS) and broadband dielectric spectroscopy (BDS). Analyzing the WAXS and BDS results indicated that mobile ion types and chemical structure of the pendant groups controlled structural heterogeneity and ion conduction of the PILs below Tg. The normalized heterogeneity length extracted from WAXS data was used to correlate the structural heterogeneity and ion conduction activation energy. For the polycation samples, larger TFSI– mobile anion results in a higher packed structure than small Cl– while in the polyanion samples inverse trend was observed. The calculated activation energy of the dc conductivity below Tg is quantitatively correlated to the structural heterogeneity obtained from nano structure analysis using WAXS. This suggested increasing the spatial heterogeneity of the PILs results in the reduction of the activation energy of long-range ion motions. These results highlight the role of spatial heterogeneity in designing efficient polymerized ionic liquids

Imitation of human muscle by using an electromechanical system

Abstract Humanity is increasingly approaching the dream of making humanoid robots that have been imaginary for many years with advancing technology. Designs that are close to perfect in humanoid or animal-like robots emerge with the research and development studies carried out by researchers on this subject. In order to develop these robots, the movement mechanism of humans and animals must be examined again. Robots will work in place of people and can be used in wars with the development of these systems. In this study, the usability and performance of the linear actuator, which is widely used in various mechatronic systems as a linear motion provider, in the artificial muscle mechanism have been tested. Moreover, it tried to create a similar prototype by examining the working logic of skeletal muscle. The different aspect of the study is to indicate how the motion energy can be gained without using the conventional motors that are used in robot technologies. The artificial musculature is formed by arranging the electromagnets in a row, leaving a gap between them. The desired length of movement is formed as a result of the activated electromagnets gaining magnetism and closing the gap. In the study, the maximum load that the artificial muscle can pull according to the given voltage was 130.18 N and the average maximum gap length of each sarcomere was 1.68 mm. The efficiency of artificial muscle was found to be 56% compared to human muscle.

An electromagnetic rotary-translational motion energy harvester enabled by magnetic-regulated magnetic sphere

This paper describes an electromagnetic energy harvester that uses a rotary-translational magnetic regulation system to convert vibration energy into electrical power. The system consists of a springless magnetic sphere multiple rolling in a cavity and multiple magnetic disks evenly embedded in the cavity. Multiple magnetic disks are arranged with alternating magnetic pole shifts, with the goal of modulating the traditional erratic rolling of the magnetic sphere into a multi-circle regular movement with the change of the magnetic disk’s magnetic pole. Faraday’s law is used to create electromotive forces in coils due to the rotating magnetic moment. The output voltages are measured and analyzed using motion and rotation excitation, parallel, and series coil connections. Experiments on the magnetic sphere with and without magnetic regulation are carried out using a manufactured apparatus. The magnetic sphere with magnetic regulation has periodic and regular output characteristics, according to the results of the experiments. A prototype electromagnetic energy harvester can charge a 0.47 F capacitor to more than 0.40 V in less than 450 s under rotating excitation. The device's energy and effective average power are calculated to be 10.62 J and 23.60 mW. • Random motion in any orientation can be transformed into a multi-circle rotational motion. • The sphere in roll motion with the magnetic disks' regulating system has been used to harvest ambient vibration. • It is the appropriate choice for the rotation energy harvesting, which gets rid of the limited degrees of freedom.

Immediate effect of MET of shoulder horizontal abductors and active sleeper stretch on glenohumeral internal rotation deficit in Indian lawn tennis players

IntroductionThroughout the throwing motion, the glenohumeral joint (GHJ) achieves extraordinary movement speeds, forces and ranges of motion (ROMs). When the dominant arm is abducted 90°, the shoulder (GHJ) external rotation ROM is usually greater than the non-dominant arm's. Stretching, in any form, effectively increases the joint range of motion. Stretches that increase range of motion, whether active, passive, or muscle energy technique (MET), have been proven to help manage and prevent injuries related with glenohumeral internal rotation deficit (GIRD). The goal of this study was to see which protocol would be the most beneficial in terms of having an immediate effect on this condition, and if either of the stretches would produce a better result, then that could be utilised to treat athletes, the lawn tennis players in this study, to improve their posterior shoulder flexibility. Material and method30 tennis players of 16–30 years of age with GIRD were recruited for the study. The sample was taken from different lawn tennis courts in Delhi. A detailed assessment of GIRD was done. In order of recruitment for the study, each odd subject was given MET of shoulder horizontal abductors first and Active Sleeper Stretch after an interval of 24 h. The order was reversed for every even subject. Range of motion was compared with before and after the protocols readings. ResultThe result of the study says that the active sleeper stretch increases the internal rotation (IR) range of motion in 30 subjects by an average of 4.8o ± 1.95 and MET of shoulder horizontal abductor by an average of 4.73o ± 2.18. ConclusionThere are limitations of both the techniques over each other. Active sleeper stretch cannot be done by impingement syndrome athletes and MET cannot be done alone. Therefore, either of them can be used according to the convenience of the athlete.

Dynamic study of pendulum systems through smartphone-based laboratory experiments

The dynamic study of pendulum systems is considered an indispensable subject for physics and mechanics students in colleges and high schools. In this paper, a detailed methodology is given concerning the use of smartphones in pedagogical practical work for studying the dynamics of pendulum systems. Whereas, three aspects have been discussed through three cases concerning the study of the oscillatory motion, trajectories, and the energy aspect. Besides, some recommendations were provided regarding the process of data acquisition and curve-fitting processing to mitigate measurement errors. Experimental results exhibit a good agreement with theoretical results regarding the period of motion, trajectories, and mechanical energy. This makes the smartphone highlights a real opportunity to be a useful instrument to perform an overall study of the pendulum systems, the thing that was impossible without the intervention of professional equipment.

การสร้างแบบทดสอบวินิจฉัยมโนทัศน์ที่คลาดเคลื่อนแบบสี่ชั้นวิชาฟิสิกส์ เรื่อง งานและพลังงานสำหรับนักเรียนระดับชั้นมัธยมศึกษาปีที่ 4 สำนักงานเขตพื้นที่การศึกษามัธยมศึกษาเขต 18

This research aimed to 1) construct the four-tier diagnostic test for detecting the physics Misconceptions on work and energy of motion for the  grade students, 2) to validate the difficulty, the discrimination, the validity and the reliability of the test, 3) detecting physics misconceptions, and 4) to create the teacher manual of the test. The sample of the research was selected by stratified random sampling technique. The sample consisted of 701 students who studied in  and  grade of schools under Chon Buri–Rayong Secondary Educational Service Area Office. The research instrument was a 20-item of four–tier diagnostic test for detecting the physics misconceptions in work and energy.The research findings revealed that diagnostic test met the requirements of content validity with IOC indices which ranged between 0.80 and 1.00. The construct validity was between 0.72 and 0.95. The difficulty of all items ranged between 0.38 and 0.44. The discrimination index was calculated by Whitney and Sabers which ranged between 0.50 and 0.63. The reliability of the test according to Livingston Method ranged from 0.91 to 0.97. The cutting score calculated by Angoff Methed was 13 points from 20 points. The diagnostic test results showed that all most of the students had correct conception in power, did not understand the concept in meaning of kinetic energy, misconceived in power transform of the law of conservation and error in the meaning of conservation forces.

Tapping-Actuated Triboelectric Nanogenerator with Surface Charge Density Optimization for Human Motion Energy Harvesting.

In this article, triboelectric effect has been used to harvest mechanical energy from human motion and convert it into electrical energy. To do so, different ways of optimizing the energy generated have been studied through the correct selection of materials, the design of new spacers to improve the contact surface area, and charge injection by high-voltage corona charging to increase the charge density of dielectric materials. Finally, a triboelectric nanogenerator (TENG) has been manufactured, which is capable of collecting the mechanical energy of the force applied by hand tapping and using it to power miniaturized electronic sensors in a self-sufficient and sustainable way. This work shows the theoretical concept and simulations of the proposed TENG device, as well as the experimental work carried out.

Motion energy analysis during speech tasks in medication-naïve individuals with at-risk mental states for psychosis

Movement abnormalities are commonly observed in schizophrenia and at-risk mental states (ARMS) for psychosis. They are usually detected with clinical interviews, such that automated analysis would enhance assessment. Our aim was to use motion energy analysis (MEA) to assess movement during free-speech videos in ARMS and control individuals, and to investigate associations between movement metrics and negative and positive symptoms. Thirty-two medication-naïve ARMS and forty-six healthy control individuals were filmed during speech tasks. Footages were analyzed using MEA software, which assesses movement by differences in pixels frame-by-frame. Two regions of interest were defined—head and torso—and mean amplitude, frequency, and coefficient of variability of movements for them were obtained. These metrics were correlated with the Structured Interview for Prodromal Syndromes (SIPS) symptoms, and with the risk of conversion to psychosis—inferred with the SIPS risk calculator. ARMS individuals had significantly lower mean amplitude of head movement and higher coefficients of movement variability for both head and torso, compared to controls. Higher coefficient of variability was related to higher risk of conversion. Negative correlations were seen between frequency of movement and most SIPS negative symptoms. All positive symptoms were correlated with at least one movement variable. Movement abnormalities could be automatically detected in medication-naïve ARMS subjects by means of a motion energy analysis software. Significant associations of movement metrics with symptoms were found, supporting the importance of movement analysis in ARMS. This could be a potentially important tool for early diagnosis, intervention, and outcome prediction.

Investigation of the Physical Mechanism of Acoustic Attenuation in Viscous Isotropic Solids

The traditional acoustic attenuation coefficient is derived from an analogy of the attenuation of an electromagnetic wave propagating inside a non-ideal medium, featuring only the attenuation of wave propagation. Nonetheless, the particles inside viscous solids have mass, vibrating energy, viscosity, and inertia of motion, and they go through transient and damping attenuation processes. Based on the long-wavelength approximation, in this paper, we use the energy conservation law to analyze the effect of the viscosity of the medium on acoustic attenuation. We derive the acoustic attenuation coefficient by combinations of the dynamical equation of a solid in an acoustic field with conventional longitudinal wave propagation under a spring oscillator model. Considering the attenuation of propagating waves and the damping attenuation of particle vibration, we develop a frequency dispersion relation of phase velocity for the longitudinal wave propagating inside viscous solid media. We find that the acoustic impulse response and vibrational system function depends on the physical properties of the viscous solid media and their internal structure. Combined with system function, the impulse response can be an excellent tool to invert the physical properties of solids and their internal structures. We select a well-known rock sample for analysis, calculate the impulse response and vibrational system function, and reveal new physical insight into creating acoustic attenuation and frequency dispersion of phase velocity. The results showed that the newly developed acoustic attenuation coefficients enjoy a substantial improvement over the conventional acoustic attenuation coefficients reported in the literature, which is essential for industrial applications; so are the dispersion characteristics.

Nonverbal Synchrony in Technology-Mediated Interviews: A Cross-Cultural Study.

Technology-mediated communication has changed the way we interact. Since the onset of the COVID-19 pandemic in March 2020, this trend became even more pronounced. Media interviews are no exception. Yet, studies on nonverbal behaviors, especially nonverbal synchrony during such mediated settings, have been scarce. To fill the research gap, this study investigated synchronized patterns between interview hosts’ and guests’ facial emotional displays and upper body movement during mediated interviews recorded in the countries in Western (mainly the US, with the addition of the UK) and Eastern cultures (Japan). The interviews were categorized into information- or entertainment-driven interviews, depending on the social attributes of the guest. The time series of the valence in facial displays and upper body movement was automatedly measured using FaceReader and Motion Energy Analysis software, respectively, which was analyzed in terms of simultaneous movements, a primary component of synchrony. As predicted, facial synchrony was more prevalent in information-driven interviews, supporting the motivational and strategic account of synchrony. In addition, female-hosted interviews had a higher degree of synchrony, especially in information-driven interviews. Similar patterns were seen in movement synchrony, although not significant. This study is the first evidence of synchrony in technology-mediated interviews in which a host and a guest appear on split-screen to inform or entertain audiences. However, no cultural differences in synchrony were observed. Situational demands in front of the interactants and the goal-driven nature of communication seemed to play a more prominent role than cultural differences in nonverbal synchrony.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10919-022-00416-3.

Solution‐Tube‐Based Volume Effect Triboelectric Nanogenerator with Salt and pH Sensitivity

AbstractDue to the advantages of natural softness and flexibility of water, liquid–solid‐based triboelectric nanogenerators (TENGs) have aroused wide attention recently and much effort has been devoted to improving its output performance. Herein, the performance of liquid–solid‐based TENG is greatly improved through two simple steps. First, an end electrode is added into the traditional tube‐based TENG and the volume effect is successfully realized, with the output voltage improved by ≈40 times to 240 V. Then, the output voltage of the tube‐based TENG can be further improved to 461 V by replacing water with NaOH solution and an impressive peak power density of 1910 Wm−3 and an average power density of 459 Wm−3 can be achieved. Additionally, the demonstration shows that the solution‐tube‐based volume effect TENG can work well at various operation modes and generate power from multiple mechanical energy sources. In addition to wearable human motion energy recovery, wave energy recovery, and electrochemical cathodic protection systems, the device also shows its application potential in biochemical sensing based on the solute concentration‐dependent output signal.

Fluorescence calorimetry of an ion crystal

Motivated by the challenge of identifying intruder ions in a cold ion crystal, we investigate calorimetry from emitted fluorescence light. Under continuous Doppler cooling, the ion crystal reaches a temperature equilibrium with a fixed level of fluorescence intensity and any change in the motional energy of the crystal results in a modification of this intensity. We theoretically determine the fluorescence rate of an ion crystal as a function of the temperature, assuming that laser light is scattered along a two-level electronic transition, which couples to the crystal's vibrations via the mechanical effects of light. We analyze how the heat dissipated by collisions of an incoming intruder ion alters the scattering rate. We argue that an energy change by an incoming ${}^{229}{\mathrm{Th}}^{10+}$ ion can be unambiguously detected within 100 $\ensuremath{\mu}\mathrm{s}$ via illuminating a fraction of a ${10}^{3}$ ion crystal. This method enables applications including capture and spectroscopy of charged states of thorium isotopes and investigation of highly charged ions.

A Self-Powered Wearable Sensor for Continuous Wireless Sweat Monitoring.

Wireless wearable sweat analysis devices can monitor biomarkers at the molecular level continuously and in situ, which is highly desired for personalized health care. The miniaturization, integration, and wireless operation of sweat sensors improve the comfort and convenience while also bringing forward new challenges for power supply technology. Herein, a wireless self-powered wearable sweat analysis system (SWSAS) is designed that effectively converts the mechanical energy of human motion into electricity through hybrid nanogenerator modules (HNGMs). The HNGM shows stable output characteristics at low frequency with a current of 15mA and a voltage of 60V. Through real-time on-body sweat analysis powered by HNGM, the SWSAS is demonstrated to selectively monitor biomarkers (Na+ and K+ ) in sweat and wirelessly transmit the sensing data to the user interface via Bluetooth.

Open Sea Lab: An integrated Coastal Ocean Observatory Powered by Wave Energy

Current advances in wave energy technologies have enabled the development of new integrated measurement platforms powered by the energy of wave motion. Instrumentation is now being deployed for the long-term observation of the coastal ocean, with the objectives of analyzing the performance of wave energy converters (WECs) and studying their interactions with the surrounding environment and marine life. In this work, we present the most relevant findings of the installation and initial operation of the Open Sea Lab (OSL), the first coastal observatory in Latin America powered entirely by a WEC device. We evaluated the preliminary data regarding the combined operation of the system, the generation of energy, and the observations obtained by the continuous monitoring of physical variables at the site. The data showed the seasonal variability of the energy produced by the WEC for a range of wave heights during the period of observation. We also investigated the rapid development of biofouling on mooring lines, junction boxes, and other parts of the system, which is characteristic of the settlement and growth of organisms in this ocean region. These analyses show how this new facility will advance our understanding of the coastal environment in the south Pacific Ocean and foster new interdisciplinary collaborations addressing environmental and technical challenges, thereby contributing to the development of wave energy on the continent.

Decoding spatiotemporal features of emotional body language in social interactions

How are emotions perceived through human body language in social interactions? This study used point-light displays of human interactions portraying emotional scenes (1) to examine quantitative intrapersonal kinematic and postural body configurations, (2) to calculate interaction-specific parameters of these interactions, and (3) to analyze how far both contribute to the perception of an emotion category (i.e. anger, sadness, happiness or affection) as well as to the perception of emotional valence. By using ANOVA and classification trees, we investigated emotion-specific differences in the calculated parameters. We further applied representational similarity analyses to determine how perceptual ratings relate to intra- and interpersonal features of the observed scene. Results showed that within an interaction, intrapersonal kinematic cues corresponded to emotion category ratings, whereas postural cues reflected valence ratings. Perception of emotion category was also driven by interpersonal orientation, proxemics, the time spent in the personal space of the counterpart, and the motion–energy balance between interacting people. Furthermore, motion–energy balance and orientation relate to valence ratings. Thus, features of emotional body language are connected with the emotional content of an observed scene and people make use of the observed emotionally expressive body language and interpersonal coordination to infer emotional content of interactions.

Co-Optimization of Motion, Communication, and Sensing in Real Wireless Channel Environments via Monte Carlo Tree Search

We consider the problem where a robot navigates from a start position to a destination and needs to sense some sites along the way. The robot collects data when sensing each site and needs to transmit all collected data to a remote station by the end of its trip, as it moves along its path, under time/energy constraints, and while operating in real wireless fading environments. Our goal is to minimize the robot's total motion and communication energy costs by co-optimizing its path, data transmission along the path, and sensing decisions, under given constraints and while considering the stochastic wireless channel. In this paper, we show how to solve this co-optimization problem efficiently and with performance guarantees. More specifically, we formulate a specially-designed Markov Decision Process (MDP) and utilize Monte Carlo Tree Search (MCTS) to efficiently and optimally solve it. While the co-dependence of communication, sensing, and motion decisions makes this joint optimization challenging, we show that by considering the transmission optimization in the terminal reward and motion actions in the state transitions, we can iteratively optimize the sensing/motion and the communication parts in different stages of MCTS, in a way that allows us to equivalently solve the original co-optimization problem efficiently. We mathematically prove the convergence of our approach, characterize its convergence speed, and derive key properties of the optimum solution. We extensively evaluate our approach in realistic wireless environments where the channel experiences path loss, shadowing, and multi-path fading and is unknown to the robot.

Versatile Carbon Nanofiber-Based Sensors.

Carbon nanofibers (CNFs) display colossal potential in different fields like energy, catalysis, biomedicine, sensing, and environmental science. CNFs have revealed extensive uses in various sensing platforms due to their distinctive structure, properties, function, and accessible surface functionalization capabilities. This review presents insight into various fabrication methods for CNFs like electrospinning, chemical vapor deposition, and template methods with merits and demerits of each technique. Also, we give a brief overview of CNF functionalization. Their unique physical and chemical properties make them promising candidates for the sensor applications. This review offers detailed discussion of sensing applications (strain sensor, biosensor, small molecule detection, food preservative detection, toxicity biomarker detection, and gas sensor). Various sensing applications of CNF like human motion monitoring and energy storage and conversion are discussed in brief. The challenges and obstacles associated with CNFs for futuristic applications are discussed. This review will be helpful for readers to understand the different fabrication methods and explore various applications of the versatile CNFs.

Design of vibro-impact electromagnetic ocean-wave energy harvesting system; an experimental study

Ocean wave energy is a stable renewable energy source, which has realistic application prospects. Based on the intermittent and irregular nature of ocean-wave, researchers have designed many ocean-wave energy harvesters, with several advantages and disadvantages. The main goal of this study is to present a new ocean wave energy harvester, which works based on the small pitch motion of moving floaters. Unlike almost all the previously presented systems, the presented ocean wave energy harvester can work in moving forward ships and boats like emergency boats. To do so, a ibro-impact system is designed to gather the kinetic energy of small pitch motions and transmit it to the vibratory part of the system via impulsive load. A mechanical rectifier that gets its input energy from the oscillations of the vibratory part, provides continuous rotations needed by the electromagnetic transducer. The governing electromechanical equation of motion for the discussed system is derived to study the effects of changing the ocean-wave properties on the application of the energy harvester. It is shown the gap size of the impact part of the system and the ocean-wave period have important effects on the output electrical energy.