Body Acceleration Research Articles

Potential of accelerometer tags for monitoring of Japanese quail (Coturnix japonica) reproductive behaviour

ABSTRACT 1. Monitoring behavioural dynamics in complex animal environments, such as poultry breeding facilities, poses a challenge. Utilising technological approaches, such as accelerometers, offers a solution to assess long-term changes in reproductive activity at an individual bird level. Specifically, these sensors measure acceleration associated with the position and movements of the body over time. However, it is important to assess the most suitable method for attaching accelerometer tags to ensure they do not negatively impact behaviour and yield high-quality data. 2. The potential of tri-axial accelerometer tags for assessing reproductive behaviour in Japanese quail was evaluated. Two attachment methods – a backpack (plastic platform with elastic bands near wing bases) and a patch (accelerometer on fabric glued to the synsacrum region) – were compared. Controls were handled similarly but without tags. Eighteen pairs of females were housed in pens and assessed immediately and 24 h after handling. After a week of habituation, a male from the same treatment group was introduced into each pen on d 8. The reproductive behaviour of the males was recorded using accelerometers and video recordings. 3. The results showed that birds with patches were able to remove their conspecific’s accelerometer and displayed an increased initial immobility response compared to the control and backpack groups. The presence of accelerometer tags did not impact male/female reproductive interactions nor fear responses to a novel object. From accelerometer recordings, male reproductive behaviour was easily identified as high amplitude fluctuations in the three axial components of the acceleration vectors, which was reflected as large values of dynamic body acceleration (VeDBA). 4. In conclusion, the use of backpacks with accelerometers is a useful strategy to address highly relevant and difficult to tackle behavioural topics such as the temporal dynamic of male reproductive behaviour within breeding groups.

Static and dynamic aspects of the principle of virtual work

AbstractThe paper presents a detailed analysis of the principle of virtual work in its statics and dynamics aspects. Special attention is paid to not exact formulation and interpretation of mechanical system motion equations based upon this principle, what is presented quite often in text books. The general form of the principle of virtual work and variational formulations of the problems in statics are presented and analyzed. Additionally, the dynamic implications of the principle of virtual work and dynamics problem formulation of a system subjected to scleronomic constraints are detailed. The basis for the formulation is the dynamic implication of the principle of virtual work that specifies the relation between the constraint reactions and the body accelerations. This relation takes the form of the variation inequality. As the result, the Gauss principle which determines the body acceleration vector is presented. Furthermore, a description of impact formulation, based upon the Carnot model, caused by the constraints is provided. The theoretical development is illustrated with examples of applications of the principle of virtual work.

Using GPS and accelerometer data to remotely detect breeding events in two elusive ground-nesting steppe birds

BackgroundModern biologging technologies allow researchers to gain a better understanding of animal movements, offering opportunities to measure survival and remotely study the breeding success of wild birds, i.e., by locating nests. This is particularly useful for species whose nests are difficult to find or access, or when disturbances can impact the breeding outcome. We developed and validated, with field data, a framework to detect nesting events by two sandgrouse species, the black-bellied (Pterocles orientalis) and pin-tailed sandgrouse (Pterocles alchata), using GPS and Overall Dynamic Body Acceleration (ODBA) data. Sandgrouses are ground-nesting, cryptic, and elusive birds with biparental incubation efforts. Because both sexes take turns to incubate, a novel framework considering when tagged individuals are on incubation duty or not needs to be designed to detect nests.ResultsWe tagged 52 birds with high-resolution GPS devices to monitor their breeding during 2021–24. Using remote tracking and field data from the first 2 years (2021–22), we first determined sex-specific time windows for incubation to maximise differentiation between incubation and non-incubation behaviours. We then used a threshold-based classification to identify incubation days and inferred the minimum number of successive incubation days needed to correctly identify a nesting event. We show how ODBA and GPS data can be used to successfully detect nests incubated for only 2 or 3 days. GPS-only data or combined GPS-ODBA data had a success rate of around 95%, whereas ODBA-only data had a success rate of 100%. Cross-validation using data from 2023 to 2024 confirmed the model’s performance, showing an overall success > 90% for GPS-only and ODBA-only data and of 85% for combined GPS–ODBA data.ConclusionsBy accurately identifying nesting events, our framework offers new opportunities to study the breeding of conservation-dependent species. Besides its applicability to ground-nesting species with biparental care and sex-specific incubation schedules, the framework can be adapted to other bird species sensitive to disturbances or with inaccessible nesting sites. By doing so, it reduces the need for nest visits and associated disturbances, as well as the carbon footprint and expenses associated with fieldwork.

Use of anti-motion sickness reading glasses in vehicles: study protocol for a cluster-randomised trial

Motion sickness, or kinetosis, is a common phenomenon and is usually induced during passive locomotion in vehicles, generated by different body accelerations when movement stimuli occur. Its main symptoms are nausea, vomiting, paleness, and sweating in the exposed individual. Thus, the anti-motion sickness glasses were developed, which work using a fluid that moves in rings arranged around the eyes. This study protocol aims to evaluate the possibility that these glasses can avoid the sensory conflict that causes motion sickness, attenuating or eliminating the symptoms of motion sickness while reading in vehicles. Therefore, a crossover study shall be conducted, in which volunteers in two groups will travel in a standard car using antikinetosis goggles while reading, covering a predetermined path, in a trajectory that will last for 15 minutes. The first group (G1) will use functional glasses on the first day of testing. The second group (G2), in turn, will start the tests using the adulterated glasses, similar to the functional ones in appearance, but without the proposed effects of reducing or eliminating symptoms. On the second day of testing, for each group, the previously unused model will be employed instead. At the end of each clinical trial day, a questionnaire based in the MSSQ-Short shall be applied, evaluating the intensity of possible symptoms, their duration and the time till their appearance. Thus, the persistence of symptoms or the appearance of some clinical improvement will be evaluated, making it possible to verify the effectiveness of the object of study.

Data-Driven Control Method Based on Koopman Operator for Suspension System of Maglev Train

The suspension system of the Electromagnetic Suspension (EMS) maglev train is crucial for ensuring safe operation. This article focuses on data-driven modeling and control optimization of the suspension system. By the Extended Dynamic Mode Decomposition (EDMD) method based on the Koopman theory, the state and input data of the suspension system are collected to construct a high-dimensional linearized model of the system without detailed parameters of the system, preserving the nonlinear characteristics. With the data-driven model, the LQR controller and Extended State Observer (ESO) are applied to optimize the suspension control. Compared with baseline feedback methods, the optimization control with data-driven modeling reduces the maximum system fluctuation by 75.0% in total. Furthermore, considering the high-speed operating environment and vertical dynamic response of the maglev train, a rolling-update modeling method is proposed to achieve online modeling optimization of the suspension system. The simulation results show that this method reduces the maximum fluctuation amplitude of the suspension system by 40.0% and the vibration acceleration of the vehicle body by 46.8%, achieving significant optimization of the suspension control.

Unsteady solute dispersion in large arteries under periodic body acceleration

The present study investigates the effect of periodic body acceleration on solute dispersion in blood flow through large arteries. Transport coefficients (i.e., exchange, convection, and dispersion coefficients) and mean concentration of the solute are analyzed in the presence of wall absorption. The solute is quickly transported to the wall of arteries with a smaller radius, whereas the opposite is true for arteries with a larger radius. In the presence of body acceleration, the amplitude of fluctuations of the convection coefficient K1(t) increases significantly as the radius of the artery increases. In contrast, an opposite scenario exists for the dispersion coefficient K2(t). The solute dispersion process becomes more effective in arterial blood flow as the radius of the artery decreases. More interestingly, in large arteries with body acceleration, the solute is convected, dispersed, and distributed more toward the upstream direction owing to flow reversal during the diastolic phase of pressure pulsation. Note that this important feature of flow reversal is solely due to periodic body acceleration. For an artery with a small radius, under the influence of periodic body acceleration, the mean concentration of solute Cm is the minimum, and more axial spread is noticed in the axial direction. In contrast, an opposite scenario arises in the artery with a large radius. Additionally, the effect of body acceleration on the shear-induced diffusion of red blood cells is discussed in blood flow.

Plunge-diving into dynamic body acceleration and energy expenditure in the Peruvian booby.

Daily energy expenditure (DEE) is the result of decisions on how to allocate time among activities (resting, commuting, and foraging) and the energy costs of those activities. Dynamic body acceleration (DBA), which measures acceleration associated with movement, can be used to estimate DEE. Previous studies of DBA-DEE correlations in birds occurred on species foraging below their thermoneutral zone, potentially decoupling the DBA-DEE relationship. We used doubly-labelled water (DLW) to validate the use of DBA on plunge-diving seabirds, Peruvian boobies (Sula variegata), foraging in waters above their thermoneutral zone (>19 °C). Mass-specific DEEDLW in boobies was 1.12 kJ/d/g, and higher in males than in females. DBA alone provided the best fitting model to estimate mass-specific DEEDLW compared to models partitioned per activity and time-budget models. Nonetheless, the model parametrizing activity at and away of their onshore breeding colony was the most parsimonious model (r=0.6). This r value, although high, is lower than all other avian studies, implying that temperature is not the main cause of DBA-DEE decoupling in birds. Time at the colony (∼80% of the day) was the largest contributor to DEE as it was the most time-consuming activity and involved nest defense. However, foraging was the most power-consuming activity (4.6 times higher activity-specific metabolic rate than resting at the colony), and commuting-flight was higher than in other gliding seabirds. In short, DBA alone can act as a proxy for DEE, opening avenues to measure the conservation energetics of this seabird in the rapidly-changing Peruvian Humboldt Current System.

Innovative Chair and System Designs to Enhance Resistance Training Outcomes for the Elderly.

This study aims to provide a safe, effective, and sustainable resistance training environment for the elderly by modifying chairs and movement systems used during training, particularly under unsupervised conditions. The research focused on investigating the effect of modified chair designs on enhancing physical stability during resistance training by involving 19 elderly participants (mean 72.1, SD 4.7). The study measured changes in the body's acceleration during movements to compare the effectiveness of the modified chairs with those commonly used in chair-based exercise (CBE) training in maintaining physical stability. A system was developed based on experimental video data, which leverages MediaPipe to analyze the videos and compute joint angles, identifying whether the actions are executed correctly. Comparisons revealed that modified chairs offered better stability during sitting (p < 0.001) and stand-up (p < 0.001) resistance training. According to the questionnaire survey results, compared to the regular chair without an armrest, the modified chair provided a greater sense of security and a better user experience for the elderly. Video observations indicated that the correct completion rate for most exercises, except stand-up resistance training, was only 59.75%, highlighting the insufficiency of modified chairs alone in ensuring accurate movement execution. Consequently, the introduction of an automatic system to verify proper exercise performance is essential. The model developed in this study for recognizing the correctness of movements achieved an accuracy rate of 97.68%. This study proposes a new chair design that enhances physical stability during resistance training and opens new avenues for utilizing advanced technology to assist the elderly in their training.

Time-energy budgets outperform dynamic body acceleration in predicting daily energy expenditure in kittiwakes, and estimate a very low cost of gliding flight relative to flapping flight.

Energy is a common currency for any living organism, yet estimating energy expenditure in wild animals is challenging. Accelerometers are commonly used to estimate energy expenditure, via a dynamic body acceleration (DBA) or time-energy budget approach. The dynamic body acceleration approach estimates energy expenditure directly from acceleration but may lead to erroneous estimates during inactivity when acceleration is zero but energy expenditure is not. The time-energy budget approach uses accelerometers and other data streams to assign a behaviour to each time step, and then calculates energy expenditure based on activity-specific metabolic rates assigned to each behaviour. Here, used GPS-accelerometry in breeding black-legged kittiwakes (Rissa tridactyla, n=80) to calculate DBA and time-energy budgets derived from simple biologging metrics (speed, wing beat frequency, GPS position). We then compared these two approaches to estimates of energy expenditure from doubly-labelled water. Energy expenditure estimated from DLW correlated with DBA, but the best model to estimate energy expenditure was based on time-energy budgets. Energy costs of flapping flight were higher than all other kittiwake behaviours (5.54 x basal metabolic rate, BMR). Energetic costs of gliding flight (0.80 x BMR) were the lowest of all behaviours, and equivalent to the cost of resting at the colony. DEE for our birds estimated from our calibration coefficients are similar to DEE for our birds estimated with the model coefficient published using different methods. We conclude that once calibrated with DLW, GPS-accelerometry provides a simple method for measuring energy expenditure in wild kittiwakes based on time-energy budgets.

Robust H∞ Control Design for Improving Handling and Ride Comfort in Semi-Active Suspension Systems

This study investigates the application of robust H∞ control design for semiactive suspension systems. The goal is to achieve a balance between ride comfort and handling. A quarter-car model is used to simulate the system's dynamics. The findings demonstrate that the robust H∞ control approach with μ-synthesis offers significant advantages compared to traditional passive control and nominal H∞ control methods. When compared to the passive system, the robust H∞ controller with μ-synthesis results in a 50% reduction in body displacement (from 0.04 meters to 0.02 meters) during a simulated road bump. It also achieves a 25% reduction in peak body acceleration (from 4 m/s² to 3 m/s²) and a 37.5% reduction in suspension deflection (from 0.04 meters to 0.025 meters). These improvements translate to a smoother ride with less body movement and improved handling due to better tire contact with the road. The μ-synthesis method specifically addresses uncertainties like passenger weight and road conditions. This leads to more consistent performance in real-world driving scenarios. Overall, this study highlights the effectiveness of robust H∞ control design in achieving a well-balanced suspension system that enhances both ride comfort and handling.

Dynamic soaring decouples dynamic body acceleration and energetics in albatrosses.

Estimates of movement costs are essential for understanding energetic and life-history trade-offs. Although overall dynamic body acceleration (ODBA) derived from accelerometer data is widely used as a proxy for energy expenditure (EE) in free-ranging animals, its utility has not been tested in species that predominately use body rotations or exploit environmental energy for movement. We tested a suite of sensor-derived movement metrics as proxies for EE in two species of albatrosses, which routinely use dynamic soaring to extract energy from the wind to reduce movement costs. Birds were fitted with a combined heart-rate, accelerometer, magnetometer and GPS logger, and relationships between movement metrics and heart rate-derived V̇O2, an indirect measure of EE, were analyzed during different flight and activity modes. When birds were exclusively soaring, a metric derived from angular velocity on the yaw axis provided a useful proxy of EE. Thus, body rotations involved in dynamic soaring have clear energetic costs, albeit considerably lower than those of the muscle contractions required for flapping flight. We found that ODBA was not a useful proxy for EE in albatrosses when birds were exclusively soaring. As albatrosses spend much of their foraging trips soaring, ODBA alone was a poor predictor of EE in albatrosses. Despite the lower percentage of time flapping, the number of flaps was a useful metric when comparing EE across foraging trips. Our findings highlight that alternative metrics, beyond ODBA, may be required to estimate energy expenditure from inertial sensors in animals whose movements involve extensive body rotations.

Mammals show faster recovery from capture and tagging in human-disturbed landscapes

Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4–7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals.

Research on Ride Comfort Control of Air Suspension Based on Genetic Algorithm Optimized Fuzzy PID

The air suspension system’s superior variable stiffness, low vibration frequency, and resistance to road impacts significantly elevate both the comfort of vehicle occupants and the overall ride quality. By effectively controlling the air suspension system, its superior characteristics can be fully exploited to enhance the overall performance of vehicles. However, the parameter tuning process of the fuzzy PID controller for air suspension involves subjectivity and blindness, which affects the performance of the suspension system. To overcome these shortcomings, a control strategy combining genetic algorithms with fuzzy PID control is proposed. This strategy involves a genetic algorithm-optimized fuzzy PID air suspension control approach specifically targeting the fuzzy PID controller for air suspension. A 1/4 two-degree-of-freedom air suspension fuzzy PID controller is designed in MATLAB 2019a, utilizing genetic algorithms to optimize the PID parameter tuning process. The ride comfort of the fuzzy PID air suspension after tuning is then investigated. In the study of ride comfort on Class B road surfaces, the simulation and experimental results were consistent. Using a genetic algorithm to optimize a fuzzy PID-controlled air suspension resulted in reductions of the root mean square values for vertical body acceleration, suspension deflection, and wheel dynamic load by 30%, 26%, and 9%, respectively, compared to passive suspension. These reductions are further improvements over the corresponding indices controlled by the fuzzy PID alone, which decreased by 23%, 18%, and 6%, respectively. Thus, the control effect of the genetic algorithm-optimized fuzzy PID is superior to that of the fuzzy PID control. This demonstrates that the fuzzy PID control of air suspension optimized by genetic algorithms can further improve the comfort of vehicle occupants and the ride comfort of driving, providing a reference for active control of air suspension systems.

A sensitive wavelength-enhanced reconstruction algorithm for track quality assessment based on measured data and vehicle dynamics

High-speed railways are extensively utilized worldwide. However, with prolonged operation, track irregularities increasingly pose significant challenges, adversely affecting the safety and stability of train operations. This paper proposes a sensitive wavelength-enhanced reconstruction algorithm based on the cmplete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) method to address this issue. This method evaluates the influence of reconstructed track irregularities on vehicle dynamic response, considering sensitive wavelengths and amplification factors. The algorithm effectively enhances these sensitive wavelengths while maintaining the integrity of the input signal, utilizing measured track irregularities. After applying the algorithm, the maximum vertical body acceleration rises by 206.09%. The study validates a coupled train model and analyzes the mapping relationship between single-wave irregularities and vertical body acceleration. Compared to random irregularities, the maximum vertical acceleration can amplify up to 122.80% under various operating conditions. The periodic sensitive wavelengths of track irregularities significantly impact the train’s dynamic response.

Small energy benefits of in-wake flying in long-duration migratory flights.

During long-distance migrations, some bird species make use of in-wake flying, which should allow them to profit from the upwash produced by another bird. While indirect evidence supports energy saving as the primary benefit of in-wake flying, measurements are still missing. We equipped migrating northern bald ibises (Geronticus eremita) with high-precision global navigation satellite system data loggers to track their position in the flock. We estimated birds' energy expenditure through different proxies, namely dynamic body acceleration (DBA), heart rate and effective wingbeat frequency. During active flapping flight, DBA estimates dropped off when in-wake compared with when not-in-wake. In addition, effective wingbeat frequency decreased, suggesting an increased use of intermittent gliding flight during in-wake periods. Heart rate varied greatly among individuals, with a clear decrease during gliding-corroborating its energy-saving function. Furthermore, we found consistent proof for decreased heart rate during in-wake flying, by up to 4.2%. Hence, we have shown that flying in the wake of another individual reduces birds' DBA, heart rate and effective wingbeat frequency, which could reflect reduced energy requirement.

A robust and fail-safe semi-active vertical damper to improve ride comfort

In recent years, the technical progress in railway engineering has led to the integration of electronic elements in suspension components that once were purely mechanical. Many studies have been carried out, developing active and semi-active suspensions. Among these, semi-active suspensions are particularly attractive due to their simpler design compared to fully active ones. In this context, this paper proposes a semi-active vertical damper to be implemented on the secondary suspension stage of rail vehicles. A prototype is developed by modifying a pre-existing passive damper through the addition of an external servo-valve which manages an additional by-pass channel between the compression and rebound chambers. The prototype is characterised on a dedicated test rig. A reduced vehicle model is then developed as the starting point in developing a sliding mode controller to manage the semi-active feature of the damper. A time-varying sliding surface containing the state of the system and car body accelerations is proposed. Finally, the damper prototype is tested on a hardware-in-the-loop test rig, focusing the experimental campaign on quantifying the damper performance, the evaluation of the controller robustness and a failure analysis to study the behaviour of the proposed solution even in the case of unexpected failures.

Design of robust active suspension system for performance improvement and vibration control of railway vehicles: An H∞andμ-synthesis perspective

The ride comfort of a high-speed railway vehicle is a significant factor in assessing its performance. Despite having sound suspension systems and efficient control algorithms, the suspension system performance deteriorates with time. Hence, in this paper, a robust active vibration control system used in railway vehicles has been proposed. For analysis, a 27-degree of freedom (DOF) model consisting of structured and unstructured uncertainties has been considered. Two different robust control techniques, [Formula: see text] and [Formula: see text]-synthesis integrated with the Kalman estimator, have been adopted. The robust stability and the robust performance of the proposed control strategies have been evaluated using the structured singular values. The time and frequency domains of the closed loop perturbed responses to random track disturbances are shown. The root mean square (RMS) values of the accelerations of the car bodies are used to compare the suggested control schemes to the passive system. The primary focus of this study is to examine the level of ride comfort provided by the railway vehicle. To achieve this, simulated findings are compared and verified against experimental data collected and reported by the Research Designs and Standards Organization (RDSO). The observational data demonstrates that the results obtained from the suggested control methods are in close agreement with the experimental findings, with a minimal disparity ranging from 2.36% to 8.81% for lateral motion and 2.84% to 6.30% for vertical motion. Also, the % improvement of RMS values with [Formula: see text]-synthesis controller confirms the enhancement of the ride comfort as compared to other techniques.

Tradeoff analysis of the energy-harvesting vehicle suspension system employing inerter element

This paper explores the vibration isolation performance and vibration energy recovery performance of an energy-harvesting vehicle suspension system employing inerter element. The study takes into account the structural changes in the suspension caused by introducing the inerter as a new type of vibration isolation element. According to the parallel-series combination of an inerter and a damper, two different structures of energy-harvesting suspension dynamic models are constructed. The mechanism of the suspension parameter uptake on vehicle ride comfort and energy-harvesting characteristics is analyzed. A multi-objective optimal design method for the energy-harvesting vehicle suspension system employing inerter element is proposed, which considers both vehicle ride comfort and energy-harvesting characteristics. A trade-off was found between suspension isolation performance and energy-harvesting efficiency. The results indicate that various structures of energy-harvesting vehicle suspension systems employing inerter element exhibit different vibration isolation performances. Compared with the conventional energy-harvesting suspension, the series structure reduces body acceleration by 15.9 %, and the root mean square (RMS) of energy-harvesting power of the suspension is 22.2 W. The parallel structure reduces the RMS of body acceleration by 14.3 % and the RMS of energy-harvesting efficiency is 56.3 %, with the RMS energy-harvesting power of 84.9 W. The parallel structure demonstrates superior overall performance.

Estimation of speed-related car body acceleration limits with quantile regression

PurposeThis study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration. Consequently, a low-cost, data-driven approach was proposed for analyzing speed-related acceleration limits in metro systems.Design/methodology/approachA portable sensing terminal was developed to realize easy and efficient detection of car body acceleration. Further, field measurements were performed on a 51.95-km metro line. Data from 272 metro sections were tested as a case study, and a quantile regression method was proposed to fit the control limits of the car body acceleration at different speeds using the measured data.FindingsFirst, the frequency statistics of the measured data in the speed-acceleration dimension indicated that the car body acceleration was primarily concentrated within the constant speed stage, particularly at speeds of 15.4, 18.3, and 20.9 m/s. Second, resampling was performed according to the probability density distribution of car body acceleration for different speed domains to achieve data balance. Finally, combined with the traditional linear relationship between speed and acceleration, the statistical relationships between the speed and car body acceleration under different quantiles were determined. We concluded the lateral/vertical quantiles of 0.8989/0.9895, 0.9942/0.997, and 0.9998/0.993 as being excellent, good, and qualified control limits, respectively, for the lateral and vertical acceleration of the car body. In addition, regression lines for the speed-related acceleration limits at other quantiles (0.5, 0.75, 2s, and 3s) were obtained.Originality/valueThe proposed method is expected to serve as a reference for further studies on speed-related acceleration limits in rail transit systems.

Human action recognition based on smart sensors

Abstract This paper focuses on human activity recognition using LSTM (Long Short-Term Memory) for handling time series data issues. Because LSTM can better deal with the correlation and long-term correlation of time-series data, the model is utilized to build a human-computer interaction action recognition system. The experimental steps include the following: first, the bracelet sensor obtains the human body acceleration signal to obtain a data set containing a variety of motion postures and preprocesses the data. Then, LSTM is used to extract the features of the dataset, and the feature vector is utilized as the input to train the model iteratively. Finally, to improve the accuracy of recognition, a variety of machine learning models will be applied to compare the performance with the LSTM model. The experimental results indicate that the proposed model can better capture the acceleration changes of human motion in various life scenes, and can accurately distinguish various sudden action patterns of the human body in daily life. This also makes the human movement behavior recognition system proposed in this study more comprehensive.