Human Footsteps Research Articles

Energy-harvesting tile incorporating an origami coupling mechanism.

We present the design and evaluation of a simple, compact and efficient electromagnetic energy harvesting tile that can be used to harness energy from footsteps. The proposed harvester incorporates a translational-rotational origami-inspired coupling mechanism to transform the axial loads exerted by human footsteps into a localized rotation of an electromagnetic generator. The coupling mechanism employs a non-rigid tunable Kresling spring, the restorative behaviour of which is tunable to maximize energy transduction from the applied load to the generator. A computational model is developed to optimize the design parameters of the mechanism, which are then utilized to fabricate a prototype of the energy harvester. The tile is tested under loading conditions that mimic a human step, where it is demonstrated that it is capable of generating 4.18 W of electrical power per step with a surface power density of 2609 μW cm-2.This article is part of the theme issue 'Origami/Kirigami-inspired structures: from fundamentals to applications'.

Piezoelectric Sensors Pressed by Human Footsteps for Energy Harvesting

Human footsteps are a sustainable energy source that is derived from kinetic energy. As a result, in this study, piezoelectric sensors placed beneath floor tiles were excited by human footsteps to provide practical electrical energy. A simple rectifying circuit with a filter was used to capture electrical power. The floor tile is 455 mm in length and 405 mm in width. Two light-emitted diodes were lit up as the actual load by utilising electrical energy obtained from the kinetic energy generated by human footsteps. The greatest attainable power that could be extracted from the suggested floor tile was 249.6 milliwatts, with an approximate cost of $10.2.

Prototyping and Performance Analysis of a Step Driven Piezoelectric Energy Generation System

This paper presents a novel approach to harness energy from human footsteps using piezoelectric sensors. With a focus on addressing the energy needs of densely populated regions such as China and India, where foot traffic is abundant, this work endeavours to convert mechanical energy from footsteps into electrical energy. A prototype hardware model has been designed and presented to generate power through human foot movement, employing piezoelectric sensors arranged in series and connected via a rectifier diode to charge a battery. Additionally, a voltage booster is integrated to amplify voltage output, while an inverter facilitates the conversion of DC to AC power. Experimental investigations were conducted by varying the weights of individuals to establish a correlation between weight and resulting voltage outputs, culminating in a graphical representation of the data. The outcomes of our study showcase the feasibility of tapping into untapped energy reservoirs from foot traffic, thereby presenting promising applications for urban settings. This work contributes towards addressing energy challenges prevalent in densely populated areas and underscores the potential of piezoelectric energy harvesting technology as a sustainable energy solution.

Energy Harvesting Floor Tile Using Piezoelectric Patches for Low-Power Applications

Abstract Purpose One of the sustainable energy sources derived from kinetic energy is human footsteps. This research sought to find a substitute for conventional power sources to lessen dependence on them. As a result, a floor tile excited by human footsteps was demonstrated and presented to generate usable electrical power. Methods Piezoelectric patches, hot melt glue sticks, wood plates, and foam plates are just a few of the commercially available materials used in the suggested technique, making it suitable and practical. In addition to the components, uncomplicated circuits like a voltage multiplier and rectifier with a capacitance filter were employed for the electrical power capture. The proposed prototype has a length of 455 mm and a width of 405 mm. Results Two LEDs were effectively illuminated as an actual load using electrical energy collected from human footsteps. The maximum useful power that could be harvested successfully via the proposed floor tile (one tile) was 246 mW, with an approximate cost of $10.2. Conclusions Designing an array of footsteps-based energy harvesting tiles covering broad areas to maximize the harvested power could be considered as a future work. Moreover, the number of pedestrians variable can be also studied for the proposed design of this study in a real excitation environment such as a railway station, subway station, street, discotheque, and wedding festival hall.

Ubiquitous Gait Analysis through Footstep-Induced Floor Vibrations.

Quantitative analysis of human gait is critical for the early discovery, progressive tracking, and rehabilitation of neurological and musculoskeletal disorders, such as Parkinson's disease, stroke, and cerebral palsy. Gait analysis typically involves estimating gait characteristics, such as spatiotemporal gait parameters and gait health indicators (e.g., step time, length, symmetry, and balance). Traditional methods of gait analysis involve the use of cameras, wearables, and force plates but are limited in operational requirements when applied in daily life, such as direct line-of-sight, carrying devices, and dense deployment. This paper introduces a novel approach for gait analysis by passively sensing floor vibrations generated by human footsteps using vibration sensors mounted on the floor surface. Our approach is low-cost, non-intrusive, and perceived as privacy-friendly, making it suitable for continuous gait health monitoring in daily life. Our algorithm estimates various gait parameters that are used as standard metrics in medical practices, including temporal parameters (step time, stride time, stance time, swing time, double-support time, and single-support time), spatial parameters (step length, width, angle, and stride length), and extracts gait health indicators (cadence/walking speed, left-right symmetry, gait balance, and initial contact types). The main challenge we addressed in this paper is the effect of different floor types on the resultant vibrations. We develop floor-adaptive algorithms to extract features that are generalizable to various practical settings, including homes, hospitals, and eldercare facilities. We evaluate our approach through real-world walking experiments with 20 adults with 12,231 labeled gait cycles across concrete and wooden floors. Our results show 90.5% (RMSE 0.08s), 71.3% (RMSE 0.38m), and 92.3% (RMSPE 7.7%) accuracy in estimating temporal, spatial parameters, and gait health indicators, respectively.

Analysis of Acoustic Signals of Footsteps from the Piezoelectric Sensor

Some materials can change their electrical polarization under the influence of a mechanical stress due to the piezoelectric effect. This stress-induced change in polarization produces a potential difference across the material. For this reason, the piezoelectric material generates an electrical signal when it is subjected to a pressure from acoustic energy. In this study, analysis of acoustic signals of footsteps from the piezoe-lectric sensor, especially for human footsteps, have been studied by considering the analytical relationship between the electrical signal generated from the sensor and the acoustic signal that provides the effect. We analyzed the acoustic signal data by assuming that the electrical output voltage of the piezoelectric sensor completely coincides with the frequency of the acoustic signals. The original signal was pre-processed using filtering systems and analyzed by the fast Fourier transform and power spectral density methods to extract descriptive spectral features of the signal. This preliminary study proposed a method as a sensor based piezoelectric security system to detect the acoustic signals that can indicate possible dangers to the safety of people or property. The source of the acoustic signal can be determined by matching it with the existing database using machine learning algorithms like face recognition systems for future goals.

Increasing the Effectiveness of Electricity-Generating Floors Through the Mechanical Energy of DC Generators

The increasing electricity consumption of the Indonesian population requires renewable energy as an alternative to electricity generation supplies. Renewable energy can be formed through mechanical energy in its simplest form, namely in the form of a footrest. Generally, energy-harvesting floors that utilise human footsteps are designed with piezoelectric sensors. This sensor is responsible for converting mechanical energy into electrical energy. However, the power generated from piezoelectrics is only around 0.041 μW to 240.59 μW. So, in this study, an alternative design for a footstep floor is proposed capable of harvesting electrical energy using a DC generator. The proposed platform consists of a platform design that utilises the translational motion of the gears on the gear rack and is assisted by four springs surrounding the sides of the iron plate. Apart from that, the platform has a power management and storage system. Unlike controllers in general, solar charger controllers are used for charging (voltage and current in the accumulator) and flowing current to the load (lights). The subjects used in this floor test ranged from 20-100 kg. Compared to floors that use piezoelectrics, the results are that floors with DC generators experience an increase in power of around 0.62%. Hence, DC generators are more effective in harvesting electrical energy.

Design of Two-Stage Force Amplification Frame for Piezoelectric Energy Harvester

This paper describes the design of a two-stage force amplification frame for the piezoelectric energy harvester to capture mechanical energy from walking human footsteps. The frame design optimises the stress distribution to improve the force amplification ratio on the existing footstep energy harvesters. The magnification of the input force exerted on a piezoelectric stack increases the system's power output. A combination of single and compound two-stage frame design with additional linkage support was proposed, which maximise the conversion of tension to compression forces. The proposed frame also significantly reduces the maximum displacement of the frame to ensure walking comfort. The frame is tested with the input force of 85 N to 120 N based on the adult footstep during walking and running. The simulated results show that the proposed frame has a force amplification ratio of 25.3, an 11.85% improvement from the existing frames. The frame also limits the maximum displacement to 1.02 mm, 22.14% compared to the existing frames.

Pump Insole with Mini AC Generator for Emergency Energy

—In innovative research, human footsteps are harnessed as a backup energy source. Researchers have developed shoe insoles equipped with a mini AC generator, which efficiently converts mechanical energy into electrical energy. This generator incorporates gears, a diode, capacitors, and an integrated circuit to regulate the output voltage, maintaining a steady 5 V. The electrical energy is stored in a battery via a DC step-up mechanism. When activated, this setup produces 4.99 V, 9.1 A, and 36.37 W of power. The study employed a three-cell storage battery with a capacity of 1800mAh for temporary energy storage. Charging the battery required 40 pumps, consuming 45.46 watts. Renewable energy sources, such as this innovative use of human footsteps, offer sustainability, environmental friendliness, and long-term cost-effectiveness. By converting mechanical energy into electrical energy, the mini AC generator embedded in the shoe insoles maximizes the utilization of human movement. This electrical energy is efficiently stored in a battery for future use through the DC step-up mechanism. The study’s findings highlight the potential of tapping into renewable energy sources to meet our energy needs sustainably.

A power generation roadbed based on direct current triboelectric nanogenerators for human kinetic energy harvesting

ABSTRACT As the foundation of intelligent cities, many intelligent sensors require energy to support their work, such as batteries. Harnessing energy from the environment or human movement is a viable solution to this issue. The device which collects this part of energy and convert it into electric energy, can supply electricity to electrical appliances. This research proposes a human kinetic energy collection device based on a direct current triboelectric nanogenerator. Compared to the traditional TENG, the spinning energy collector triboelectric nanogenerator (SEC-TENG) can directly output direct current without a rectifier unit. By combining the SEC-TENG with the rack and pinion mechanism, the vertical motion can convert into rotary motion to drive the SEC-TENG to generate electric energy. The best-matched impedance of the device is 1 MΩ, and the device has a power generation performance of 450 V open circuit voltage and 11 µA short circuit current at a rotational speed of 300 r/min. The device can collect the kinetic energy of human footsteps and pedaling actions as a power generation roadbed, which provides electricity to the sensors on the roadside. It provides a potential energy supply plan for constructing intelligent cities.

SEISMIC WAVE RECORDER DESIGN FOR DEVELOPMENT FOOTSTEP HUMAN DETECTION ALGORITHMS

The article shoving the results of development seismic signal recorder for purpose of registration human footstep seismic signals. Design of recorder was adopted for collection seismic signals and store it on PC, for next seismic signal processing and creation signal detection and classification algorithms.
 The article provides an overview of the types of seismic waves, their classification is given. The conditions for the propagation of seismic waves are determined, and the features of Rayleigh waves are clarified. The design structure of the seismic sensor has been developed. The specifics of the functioning of the seismic sensor are described, the place and conditions of power supply and placement of the external interface are recognized. The specifics of using the sensor of an electromechanical transducer - geophone and the features of measurements using a stationary earth are described. It is shown that the development of a seismic signal sensor circuit implies the placement of input amplifiers in its structure. The main amplitude-frequency and phase-frequency characteristics of the geophone are presented. Geophone equivalent circuit, amplifier circuit, low-pass filter circuit are presented. Illustrations of types of seismograms are given, recommendations on the features of digital signal processing are given. The order of seismic signal processing is connected with its transmission from the sensor through the amplifying stage, passing through a low-pass filter in order to minimize noise and interference. The next step is to send a signal to the ADC. From the presented graphs of sensitivity and phase shift of the geophone, it follows that special attention should be paid to the curve corresponding to the sensor with an open output. This configuration of the sensor is optimal in the context of the formation of the maximum equal frequency response.
 As papers result was proposed structural and schematic design for all main recorders blocks and software features that required for properly using recorder. Tests in real conditions on test sites have shown the correctness of the choice of schemes of technical solutions for the task of registering seismic waves.

Engineering Triboelectric Charge in Natural Rubber-Ag Nanocomposite for Enhancing Electrical Output of a Triboelectric Nanogenerator.

An environmentally friendly triboelectric nanogenerator (TENG) is fabricated from a natural rubber (NR)-Ag nanocomposite for harvesting mechanical energy from human motions. Ag nanoparticles (AgNPs) synthesized with two different capping agents are added to NR polymer for improving dielectric constant that contributes to the enhancement of TENG performance. Dielectric constant is modulated via interfacial polarization between AgNPs and NR matrix. The effects of AgNP concentration, particle size and dispersion in NR composite, and type of capping agents on dielectric properties and electrical output of the NR composite TENG are elucidated. It is found that, apart from AgNPs content in the NR-Ag nanocomposite, cations of CTAB capping agent play important roles not only on the dispersion of AgNPs in NR matrix but also on intensifying tribopositive charges in the NR composite. In addition, the application of the NR-Ag TENG as a shoe insole is also demonstrated to convert human footsteps into electricity to power small electronic devices. Furthermore, with the presence of Ag nanoparticles, the fabricated shoe insole also exhibits antibacterial property against Staphylococcus aureus that causes foot odor.

An electromagnetic energy harvester for applications in a high-speed rail pavement system

Energy harvesting from ambient environment is one of the effective solutions to supply power for low power electronic devices. There are still some challenges such as poor space utilization and low power density for pavement energy harvesters. In this paper, an electromagnetic energy harvester with the double rockers is proposed to harvest the human footstep energy from high-speed rail pavement environment. Combined with two one-way bearings, the proposed double-rocker structure converts up and down motion of plate into a unidirectional rotation motion of the shaft. As the effect of the inertia flywheel, the velocity attenuation of the shaft of generator is slowed down. The dynamic model of the energy harvester with the engagement and disengagement phase is explored. Moreover, the input force and the angular velocity are simulated under the input of the various sinusoidal displacements and frequencies. The simulation and experimental results show that it can obtain the maximum output power of 466.6 mW under the vibration frequency of 5 Hz and the displacement of 10 mm. Further, the inertia flywheel can enhance the system stability and achieve the improvement of average output power by 49.45 % compared with no flywheel system. A pavement block with four energy harvesters is assembled and the actual field test proves it can obtain the maximum voltage of 54.4 V and the output power of 1.034 W, which proves the proposed electromagnetic energy harvester has great potential to achieve self-powered monitoring system and power for the low power electronic devices in high-speed rail environment.

Acoustic scene analysis using analog spiking neural network

Sensor nodes in a wireless sensor network for security surveillance applications should preferably be small, energy-efficient, and inexpensive with in-sensor computational abilities. An appropriate data processing scheme in the sensor node reduces the power dissipation of the transceiver through the compression of information to be communicated. This study attempted a simulation-based analysis of human footstep sound classification in natural surroundings using simple time-domain features. The spiking neural network (SNN), a computationally low-weight classifier derived from an artificial neural network (ANN), was used to classify acoustic sounds. The SNN and required feature extraction schemes are amenable to low-power subthreshold analog implementation. The results show that all analog implementations of the proposed SNN scheme achieve significant power savings over the digital implementation of the same computing scheme and other conventional digital architectures using frequency-domain feature extraction and ANN-based classification. The algorithm is tolerant of the impact of process variations, which are inevitable in analog design, owing to the approximate nature of the data processing involved in such applications. Although SNN provides low-power operation at the algorithm level, ANN to SNN conversion leads to an unavoidable loss of classification accuracy of ∼5%. We exploited the low-power operation of the analog processing SNN module by applying redundancy and majority voting, which improved the classification accuracy, taking it close to the ANN model.

Design of a More Efficient Rotating-EM Energy Floor with Lead-Screw and Clutch Mechanism

There is an interest in harvesting energy from people’s footsteps in crowded areas to power smart electronic devices with low consumption. The average power consumption of these devices is approximately 10 μW. The energy from our footsteps is green and free, because walking is a routine activity in everyday life. The energy floor is one of the most efficient pieces of equipment in vibration-based energy harvesting. The paper aims to improve the previous design of the energy floor—called Genpath—which uses a rotational electromagnetic (EM) technique to generate electricity from human footsteps. The design consists of two main parts of (1) the EM generator, including the lead-screw mechanism for translation-to-rotation conversion, and (2) the Power Management and Storage (PMS) circuit. The improvement was focused on the part of the EM generator. A thorough investigation of the design components reveals that the EM generator shaft in the previous Genpath design cannot continuously rotate when the floor-tile reaches the bottom end, resulting in no energy gain. Therefore, a one-way clutch is implemented to the system to disengage the generator shaft from the lead-screw motion when the floor-tile reaches the allowable displacement. During the disengagement, the EM generator shaft still proceeds with a free rotation and could generate more power. In our analysis, the dynamic model of the electro-mechanical systems with the one-way clutch was successfully developed and used to predict the energy performances of the VEH floors and fine-tune the design parameters. The analytical result is shown that the spring stiffness mainly affects the force transmitted to the EM generator, and then the induced voltage and power of the generator, thus, the value of the stiffness is one of the critical design parameters to optimize. Finally, the new prototype consisting of 12-V-DC generator, mechanisms of lead-screw and clutch, as well as coil springs with the optimal stiffness of 1700 N/m was built and tested. The average energy produced by the new prototype is 3637 mJ (or average power of 3219 mW), per footstep which is 2935 mJ greater than that of the previous design. Moreover, to raise the social awareness about energy usage, the sets of Genpath have been used to organize an exhibition, “Genpath Empower our Journey”. The people who stroll forward on the paths can realize how much energy they gain from their footsteps.

Flexible polymer-based triboelectric nanogenerator using Poly(vinylidene fluoride) and bombyx mori silk

This paper demonstrates a flexible triboelectric nanogenerator (TENG) using Poly(vinylidene fluoride) (PVDF) and silk by exploiting their inherent susceptibility for gaining and losing electrons. Bombyx mori silk possesses a strong capability of losing electrons whereas PVDF has the penchant for gaining electrons. Hence the combination of silk and PVDF could be explored as a novel and unique triboelectric pair for the fabrication of triboelectric nanogenerator. With this motivation, silk-PVDF-based TENG was fabricated on flexible substrate along with the systematic evaluation of its output performance. The primary objective of this paper is divided into two major parts. Initially, a comprehensive study was carried out to investigate the maximum output voltage of the TENG and its correlation with the morphology and composition of PVDF films. The structural optimization of the TENG was also performed in order to deduce the maximum output. Finally, various practical applications of silk-PVDF-based TENG were demonstrated. Through proper optimization, the maximum short circuit current and open circuit voltage acquired from the TENG was experimentally found out to be 11.3 μA and 611 V (peak to peak value), respectively. A relatively high output power density of 1.85 W/m2 was obtained from the optimized nanogenerator for a load resistance of 10 MΩ. The efficacy of this prototype was investigated by powering up commercial red LEDs, charging of capacitors, and harvesting energy from human body movement. The TENG is not only capable to light up 56 commercial red LED bulbs but also is able to harvest mechanical energy from body motion. The highest amount of energy was scavenged from human footsteps.

Footstep Power Generation using Piezo Electric Sensors

The country's population is growing, and as a result, so is the demand for electricity. The amount of energy squandered is also rising in many different ways simultaneously. The primary approach is to regenerate this energy in a form that can be used. In this project, human footsteps are used to generate electricity, which is then used to recharge the battery. A battery that can be used to charge electronic gadgets stores the power. The Atmega 328 processor powers this system, which also includes an Arduino IDE, an RFID sensor, a USB cable, and an LCD. The system goes into registration mode when we turn it on. We are able to add three users. After each user has logged in, the system prompts them to swipe their cards and connect their chargers. Every user initially receives 5 minutes of charging time by default.

Design and Comparative Study of a Small-Stroke Energy Harvesting Floor Based on a Multi-Layer Piezoelectric Beam Structure.

Recently, research on the energy harvesting floor is attracting more and more attention due to its possible application in the smart house, invasion monitoring, internet of things, etc. This paper introduced a design and comparative study of a small-stroke piezoelectric energy harvesting floor based on a multi-layer piezoelectric beam structure. The multi-layer piezoelectric beams are designed based on simply supported beams in an interdigitated manner. Theoretical analysis is explored to find out the beam number and layer number of the structure. Through this design, the input power from the human footsteps was effectively utilized and transformed into electrical power. The designed piezoelectric energy harvesting floor structure was tested by our designed stepping machine, which can simulate the stepping effect of a walking human on the floor with different parameters such as stepping frequency. Comparative studies of the energy harvester are carried out regarding different stepping frequencies, external circuits, and initial beam shapes. The experimental results showed that the maximum output power of a group of four-layer prototypes was 960.9 µW at a stroke of 4 mm and a step frequency of 0.83 Hz, with the beams connected in parallel.

Rancang Bangun Alat Pengukur Jarak Tempuh Lari Laun Menggunakan Sensor Inertial Measurement Unit (IMU) Berbasis Mikrokontroler

Jogging is a form of trotting or running at a slow or leisurely pace. So far, the measurement of running distance is determined by wearables Global Positioning System (GPS) and pedometers. The use of wearables with GPS commonly used by joggers cannot be used in indoor conditions. In addition, the use of a pedometer for measuring the number of steps cannot calculate the specific distance due to the inconsistency of human footsteps. This study aims to design a device to measure the distance traveled in jogging. To measure the distance traveled in a run, an Inertial Measurement Unit (IMU) sensor can be used with a linear acceleration output then reduce the measurement noise by using a Kalman Filter. The acceleration signal is processed into a velocity signal and the velocity signal is processed into a distance signal through integration. From the results of the prototype design, it is able to measure a distance of 25m with an error of 0.78%, a distance of 50m with 0.53% and a distance of 75m with 0.22%.

Boosting the Power Output of a Cement-Based Triboelectric Nanogenerator by Enhancing Dielectric Polarization with Highly Dispersed Carbon Black Nanoparticles toward Large-Scale Energy Harvesting from Human Footsteps

Boosting the Power Output of a Cement-Based Triboelectric Nanogenerator by Enhancing Dielectric Polarization with Highly Dispersed Carbon Black Nanoparticles toward Large-Scale Energy Harvesting from Human Footsteps