Low-cost System Research Articles

Design and Implementation of High-reliability, Low-cost Automotive LED Driver System

Design and Implementation of High-reliability, Low-cost Automotive LED Driver System

A NOVEL COST-EFFECTIVE PRESSURE SENSOR BASED FLOOD MONITORING SYSTEM WITH IOT

Floods are one of the most frequent and destructive natural hazards in the world. Early warning and flood monitoring is beneficial in the response and preparedness for this hazard. This paper presents a novel, low-cost flood monitoring system for disaster prevention, based on a pressure sensor. The system comprises a state-of-the-art microcontroller, a pressure sensor, and a security element. It is connected to an Internet of Things (IoT) cloud service, allowing for further data processing, interaction, and storage. The sensor data is processed to provide real-time flood measurements. The calibration data obtained from the designed system demonstrates a linear correlation between the water level and the sensor output. Additionally, the system was able to provide flood level measurements with an average error of 4.08% using the calibration equation, whereas a 4.40% error was obtained when using theoretical equations to determine the flood height.

Low-Cost Non-Wearable Fall Detection System Implemented on a Single Board Computer for People in Need of Care.

This work aims at proposing an affordable, non-wearable system to detect falls of people in need of care. The proposal uses artificial vision based on deep learning techniques implemented on a Raspberry Pi4 4GB RAM with a High-Definition IR-CUT camera. The CNN architecture classifies detected people into five classes: fallen, crouching, sitting, standing, and lying down. When a fall is detected, the system sends an alert notification to mobile devices through the Telegram instant messaging platform. The system was evaluated considering real daily indoor activities under different conditions: outfit, lightning, and distance from camera. Results show a good trade-off between performance and cost of the system. Obtained performance metrics are: precision of 96.4%, specificity of 96.6%, accuracy of 94.8%, and sensitivity of 93.1%. Regarding privacy concerns, even though this system uses a camera, the video is not recorded or monitored by anyone, and pictures are only sent in case of fall detection. This work can contribute to reducing the fatal consequences of falls in people in need of care by providing them with prompt attention. Such a low-cost solution would be desirable, particularly in developing countries with limited or no medical alert systems and few resources.

A systematic literature review of low-cost 3D mapping solutions

In "low-cost" solutions, ensuring economic accessibility and democratizing the availability of emerging technologies stand as pivotal considerations. This study undertakes a systematic literature review of low-cost 3D mapping solutions. Leveraging SCOPUS as the primary database, a comprehensive bibliometric analysis encompassing 1380 publications was conducted, subsequently narrowing the focus to 87 recent publications for detailed review. This research endeavors to delineate the defining characteristics of low-cost systems, elucidate their principal applications and preferred platforms, assess accessibility level, gauge the extent of innovation in both hardware and software development, explore the contributions of Deep Learning and data fusion, evaluate the consideration of data quality, and examine the contemporary relevance of photogrammetry within low-cost context. The findings demonstrate that many authors subjectively use the term low-cost to highlight qualities of a technology, methodology or sensor, but challenges arise from data quality comparisons with high-cost systems.

Development of a Low-Cost Data Acquisition System for Analyzing the Health of a Photovoltaic System

In recent years, fault diagnosis has become a major concern for ensuring the sustainability of photovoltaic systems. This article aims to develop a low-cost data acquisition device based on the Arduino card to collect data using sensors on two photovoltaic modules. Four defects were intentionally created on a photovoltaic panel and analyzed individually based on the evolution of current and voltage parameters over time. The results indicate that in the event of a fault, the current drops suddenly with a slight decrease in voltage. Under normal conditions, the maximum observed current was 3.8 A for an irradiation of 904 W/m2, compared to 2.2 A for 909 W/m2 and 32.78°C in the event of partial shading. This value further decreases to a maximum of 1.8 A for 867 W/m2 in an open circuit. The observation reveals that the partial shading fault with a disconnected bypass diode and open circuit has similar characteristics to the open circuit fault. However, it is important to note that this cannot be generalized as the fault only occurs in a configuration of two PV modules in parallel.

GazeLink: A multi-language low-cost mobile eye-gesture communication system with large language models for people with amyotrophic lateral sclerosis

Amyotrophic Lateral Sclerosis (ALS) patients who have severe motor and speech impairments mostly rely on their eyes and assistive technology to communicate. However, existing high-tech products are expensive and hard to access, while low-tech products are inefficient and restrictive. To mitigate the limitations, this research proposes GazeLink, a multi-language low-cost mobile application for ALS patients to communicate efficiently with only eye movements. First, the system recognizes user eye gestures like left or up with machine learning and a template-matching algorithm. Then, it converts the eye gestures to words through a keyboard that supports English, Spanish, and Chinese. For efficiency, the system employs Large Language Models (LLMs) to generate a suitable sentence with words typed by the user and the context. Finally, the system provides text-to-speech and social media post services for both verbal and digital eye-gesture communication. Simulations conclude that sentence generation with LLMs can reduce user keystrokes by 81% while maintaining 90% of semantic similarity. Usability studies with 30 participants show that GazeLink can recognize eye gestures with 94.1% accuracy in varying lighting. After rapidly learning the user interface in under 10 attempts, first-time participants typed sentences of various lengths with their eyes at 15.1 words per minute, which is 7.2x faster than the common low-tech solution E-Tran. Experiments demonstrate GazeLinks efficiency, learnability, and accuracy in eye-gesture text entry. The system is extremely affordable (less than $0.1 a month), portable, and easily accessible online. It also supports different users, lighting, smartphones, and languages. Product testing with ALS patients and personalized LLM models will be the next step.

Development of an Automated Low-Cost Multispectral Imaging System to Quantify Canopy Size and Pigmentation.

Canopy imaging offers a non-destructive, efficient way to objectively measure canopy size, detect stress symptoms, and assess pigment concentrations. While it is faster and easier than traditional destructive methods, manual image analysis, including segmentation and evaluation, can be time-consuming. To make imaging more widely accessible, it's essential to reduce the cost of imaging systems and automate the analysis process. We developed a low-cost imaging system with automated analysis using an embedded microcomputer equipped with a monochrome camera and a filter for a total hardware cost of ~USD 500. Our imaging system takes images under blue, green, red, and infrared light, as well as chlorophyll fluorescence. The system uses a Python-based program to collect and analyze images automatically. The multi-spectral imaging system separates plants from the background using a chlorophyll fluorescence image, which is also used to quantify canopy size. The system then generates normalized difference vegetation index (NDVI, "greenness") images and histograms, providing quantitative, spatially resolved information. We verified that these indices correlate with leaf chlorophyll content and can easily add other indices by installing light sources with the desired spectrums. The low cost of the system can make this imaging technology widely available.

Development and application of a low-cost and portable multi-channel spectral detection system for mutton adulteration

It is important to develop low-cost, fast and portable meat adulteration detection systems to ensure the meat authenticity and safety in complex market environments. A multi-channel spectral detection system for meat adulteration was developed in this study. The core hardware of the system mainly includes a designed spectral module and a Raspberry pi controller. The spectral module consists of three multi-channel spectral sensors and LED lamps with specific wavelengths, containing 18 channels covering a range of 410–940 nm. The software was developed based on PyQt5. After completing the construction of the system, the detection distance was discussed and determined to be 4 mm. Based on the spectral data collected by the developed system, the models for classifying pure mutton, pure pork, mutton flavour essence adulteration, colourant adulteration and adulterated mutton with pork were established and compared. Four intelligent optimisation algorithms were further used to improve the model performance. The results of the test set showed that the support vector classification (SVC) model optimised by a sparrow search algorithm (SSA) obtained the best classification performance, with an accuracy of 97.59% and a Kappa coefficient of 0.9696. After the SSA-SVC was incorporated into the sensor software, the system performance was evaluated using external validation samples. The overall accuracy of the system was 94.29%. The system took about 5.31 s to detect a sample, and the total weight of the system was 1.55 kg. Overall, the developed portable spectral system has considerable potential to rapidly and accurately discriminate adulterated mutton in the field.

Dynamic Characterization of Diameter for Round Surfaces using a Non-contact Optical Measurement System

Ensuring uniformity in the final round product's diameter is essential to production line operations because it permits adherence to geometry specifications and fulfills client demands. Non-contact diameter measurement systems are essential for manufacturing cost savings as well as quality monitoring. However, because of their non-linear movement, lengthy manufactured specimens like rods might be difficult to measure the diameter of precisely. Typically, analysis systems rely on costly and intricate optical components, limiting accessibility to small businesses. This research aims to address this issue by presenting a low-cost and practical optical system for measuring the diameters of round samples in continuous lines. The aim here is to obtain instant feedback through dynamic measurement and to create a continuous control mechanism that will contribute to sustainability. Experimental results show that the proposed method exhibits a high level of precision, with a measurement accuracy of 0.25% of nominal diameter.

Visible light-improved periodate activation of natural chalcopyrite particles towards effective pollutants degradation

The aim of this paper is to build an efficient and low-cost advanced oxidation system to realize the antibiotic wastewater purification which has a realistic significance. In this study, a system of visible light-assisted activation of natural chalcopyrite to activate periodate was adopted to remove tetracycline (TC). The results demonstrated that the removal efficiency (100% within 60 min) of TC in the CuFeS2/PI/Light system was significantly improved compared to the CuFeS2/PI system or PI process alone, and the degradation rates of TC in the CuFeS2/PI/Light system were 5.9 times higher than that of the CuFeS2/PI system, which is attributed to the synergistic effect of light and PI activation. The system also effectively degraded sodium butyl xanthate (SBX), chlortetracycline hydrochloride (CTC) and Rhodamine B (RhB), while the efficiency of the degradation process was further enhanced in natural water quality. The active substance quenching experiment revealed that [Formula: see text]OH, 1O2, O2[Formula: see text], IO4[Formula: see text] and IO3[Formula: see text] were the main substances to achieve effective TC removal. In addition, the cycling of Cu[Formula: see text]/Cu[Formula: see text] and Fe[Formula: see text]/Fe[Formula: see text] present in chalcopyrite improved the activation of PI. Further, visible light is conducive to the valence cycling of Cu and Fe, as well as the production of more oxidizing free radicals, thus achieving the synergy of photocatalysis and PI activation. This study provides a low-cost and efficient advanced oxidation pathway for the removal of antibiotic wastewater.

Noble-metal-free Ni(dmgH)2/CdS nanocomposite for enhanced photocatalytic H2 generation

In this study, we report an economic and noble-metal-free photosynthetic system of Ni(dmgH)2/CdS composites (dmgH = dimethylglyoxime). This system, consisting of CdS as a photocatalyst and Ni(dmgH)2 as a co-catalyst, exhibits enhanced photoresponse, accelerated charge transfer, facilitating the separation of electrons and holes, and efficient hydrogen evolution under visible light. It was found that the catalytic efficiency of CdS was significantly influenced by the loading amount of Ni(dmgH)2. An optimum activity was achieved at 10 wt% Ni(dmgH)2, resulting a stable hydrogen generation rate of 32.744 mmol h−1 g−1. This rate is nearly 98 times higher than that of bare CdS under similar conditions, indicating that Ni(dmgH)2 can be a highly efficient noble-metal-free co-catalyst for photocatalytic hydrogen evolution with CdS. The mechanism for the hydrogen evolution of the Ni(dmgH)2/CdS composites was also proposed. This study demonstrates that the combination CdS semiconductor with small proportion of transition-metal-based co-catalyst may provide a reliable platform for a stable, earth-abundant, and low-cost system for solar-to-hydrogen conversion, paving the way for promising advancements in green energy research.

ChromaFlash: Snapshot Hyperspectral Imaging Using Rolling Shutter Cameras

Hyperspectral imaging captures scene information across narrow, contiguous bands of the electromagnetic spectrum. Despite its proven utility in industrial and biomedical applications, its ubiquity has been limited by bulky form factors, slow capture times, and prohibitive costs. In this work, we propose a generalized approach to snapshot hyperspectral imaging that only requires a standard rolling shutter camera and wavelength-adjustable lighting. The crux of this approach entails using the rolling shutter as a spatiotemporal mask, varying incoming light quicker than the camera's frame rate in order for the captured image to contain rows of pixels illuminated at different wavelengths. An image reconstruction pipeline then converts this coded image into a complete hyperspectral image using sparse optimization. We demonstrate the feasibility of this approach by deploying a low-cost system called ChromaFlash, which uses a smartphone's camera for image acquisition and a series of LEDs to change the scene's illumination. We evaluated ChromaFlash through simulations on two public hyperspectral datasets and assessed its spatial and spectral accuracy across various system parameters. We also tested the real-world performance of our prototype by capturing diverse scenes under varied ambient lighting conditions. In both experiments, ChromaFlash outperformed state-of-the-art techniques that use deep learning to convert RGB images into hyperspectral ones, achieving snapshot performance not demonstrated by prior attempts at accessible hyperspectral imaging.

Validation of a micro-doppler radar for measuring gait modifications during multidirectional visual perturbations

BackgroundChanges in spatio-temporal gait parameters and their variability during balance-challenging tasks are markers of motor performance linked to fall risk. Radio frequency (RF) sensors hold great promise towards achieving continuous remote monitoring of these parameters. Research questionsTo establish the concurrent validity of RF-based gait metrics extracted using micro-Doppler (µD) signatures and to determine whether these metrics are sensitive to gait modifications created by multidirectional visual perturbations. MethodsFifteen participants walked overground in a virtual environment (VE) and VE with medio-lateral (ML) and antero-posterior (AP) perturbations. An optoelectronic motion capture system and one RF sensor were used to extract the linear velocity of the trunk and estimate step time (ST), step velocity (SV), step length (SL), and their variability (STV, SVV, and SLV). Intra-class coefficient for consistency (ICC), mean and standard deviation of the differences (MD), 95 % limits of agreement, and Pearson correlation coefficients (r) were used to determine concurrent validity. One-way repeated-measures analysis of variance was used to analyze the main and interaction effects of visual conditions. ResultsAll outcomes showed good to excellent reliability (r>0.795, ICC>0.886). Average gait parameters showed good to excellent agreement, with values obtained with the RF sensor systematically smaller than the values obtained with the markers (MD of 0.001 s, 0.09 m/s, and 0.06 m). Gait variability parameters showed poor to moderate agreement, with values obtained with the RF sensor systematically larger than those obtained with the markers (MD of 1.9 %-3.9 %). Both measurement systems reported decreased SL and SV during ML perturbations, but the gait variability parameters extracted with the radar were not able to detect the higher STV and SLV during this condition. SignificanceThe radar µD signature is a valid and reliable method for the assessment of average spatio-temporal gait parameters but gait variability measures need to be viewed with caution because of the lower levels of agreement and sensitivity to ML visual perturbations. This work represents an initial investigation for the development of a low-cost system that will facilitate aging-in-place by providing remote monitoring of gait in natural settings.

A predictive control method for multi-electrolyzer off-grid hybrid hydrogen production systems with photovoltaic power prediction

To accommodate the high-frequency and low-frequency power fluctuations of renewable energy generation with a lower system cost, a multi-electrolyzer hybrid hydrogen production system demonstrated potential for application. This study achieved the integration of proton exchange membrane electrolyzers and alkaline electrolyzers through hybrid control in a photovoltaic (PV)- transformer-electrolyzer coupled system for the first time, enabling the pre-regulation of the electrolyzer power based on the LSTM forecast of the power generation of PV, to avoid the impact of sudden large power fluctuations on the electrolyzers, with a lower system cost and higher production rate. Experiment results indicate that this hybrid hydrogen production system reduces system initial investment cost by 27.2% compared to a pure PEMWE system and increases hydrogen production by 58.7% compared to a pure AWE system.

Automatic rehabilitation exercise task assessment of stroke patients based on wearable sensors with a lightweight multichannel 1D-CNN model

Approximately 75% of stroke survivors have movement dysfunction. Rehabilitation exercises are capable of improving physical coordination. They are mostly conducted in the home environment without guidance from therapists. It is impossible to provide timely feedback on exercises without suitable devices or therapists. Human action quality assessment in the home setting is a challenging topic for current research. In this paper, a low-cost HREA system in which wearable sensors are used to collect upper limb exercise data and a multichannel 1D-CNN framework is used to automatically assess action quality. The proposed 1D-CNN model is first pretrained on the UCI-HAR dataset, and it achieves a performance of 91.96%. Then, five typical actions were selected from the Fugl-Meyer Assessment Scale for the experiment, wearable sensors were used to collect the participants’ exercise data, and experienced therapists were employed to assess participants’ exercise at the same time. Following the above process, a dataset was built based on the Fugl-Meyer scale. Based on the 1D-CNN model, a multichannel 1D-CNN model was built, and the model using the Naive Bayes fusion had the best performance (precision: 97.26%, recall: 97.22%, F1-score: 97.23%) on the dataset. This shows that the HREA system provides accurate and timely assessment, which can provide real-time feedback for stroke survivors’ home rehabilitation.

Low-Cost and Paper-Based Micro-Electromechanical Systems Sensor for the Vibration Monitoring of Shield Cutters.

Vibration sensors are widely used in many fields like industry, agriculture, military, medicine, environment, etc. However, due to the speedy upgrading, most sensors composed of rigid or even toxic materials cause pollution to the environment and give rise to an increased amount of electronic waste. To meet the requirement of green electronics, biodegradable materials are advocated to be used to develop vibration sensors. Herein, a vibration sensor is reported based on a strategy of pencil-drawing graphite on paper. Specifically, a repeated pencil-drawing process is carried out on paper with a zigzag-shaped framework and parallel microgrooves, to form a graphite coating, thus serving as a functional conductive layer for electromechanical signal conversion. To enhance the sensor's sensitivity to vibration, a mass is loaded in the center of the paper, so that higher oscillation amplitude could happen under vibrational excitation. In so doing, the paper-based sensor can respond to vibrations with a wide frequency range from 5 Hz to 1 kHz, and vibrations with a maximum acceleration of 10 g. The results demonstrate that the sensor can not only be utilized for monitoring vibrations generated by the knuckle-knocking of plastic plates or objects falling down but also can be used to detect vibration in areas such as the shield cut head to assess the working conditions of machinery. The paper-based MEMS vibration sensor exhibits merits like easy fabrication, low cost, and being environmentally friendly, which indicates its great application potential in vibration monitoring fields.

Single-carrier 220-Gbit/s sub-THz wireless transmission over 214 m using a photonics-based system.

We have demonstrated, for the first time to our knowledge, a single-carrier 220-Gbit/s wireless link over 214-m distance within hard-decision forward error correction (HD-FEC) limit using a 300-GHz-band photonics-based system incorporated with on-line digital signal processing (DSP). The approach to obtaining these results was to optimize the transmission system by using a low-noised two-tone laser system to the transmitter and receiver and to apply the unique Fresnel region of the antenna to achieve longer distances. These research results are expected to serve as a low-cost and basic communication system technology for promising backhaul wireless communications in the sixth-generation era.

Building efficient and effective OpenQA systems for low-resource languages

Question answering (QA) is the task of answering questions posed in natural language with free-form natural language answers extracted from a given passage. In the OpenQA variant, only a question text is given, and the system must retrieve relevant passages from an unstructured knowledge source and use them to provide answers, which is the case in the mainstream QA systems on the Web. QA systems currently are mostly limited to the English language due to the lack of large-scale labeled QA datasets in non-English languages. In this paper, we show that effective, low-cost OpenQA systems can be developed for low-resource contexts. The key ingredients are (1) weak supervision using machine-translated labeled datasets and (2) a relevant unstructured knowledge source in the target language context. Furthermore, we show that only a few hundred gold assessment examples are needed to reliably evaluate these systems. We apply our method to Turkish as a challenging case study, since English and Turkish are typologically very distinct and Turkish has limited resources for QA. We present SQuAD-TR, a machine translation of SQuAD2.0, and we build our OpenQA system by adapting ColBERT-QA and retraining it over Turkish resources and SQuAD-TR using two versions of Wikipedia dumps spanning two years. We obtain a performance improvement of 24–32% in the Exact Match (EM) score and 22–29% in the F1 score compared to the BM25-based and DPR-based baseline QA reader models. Our results show that SQuAD-TR makes OpenQA feasible for Turkish, which we hope encourages researchers to build OpenQA systems in other low-resource languages. We make all the code, models, and the dataset publicly available at https://github.com/boun-tabi/SQuAD-TR.

High Throughput Screening of Electroactive Bacteria Using a Cross-Bar Architecture in a 3D Design Array

Promoting extracellular electron transfer (EET) in bacteria has many widespread applications including wastewater treatment and environmental remediation. With the development of synthetic biology technologies that can alter microbial electron transfer routes and enhance their electrogenic capacity, there is a need for high throughput systems to identify the responsible genes and the consequent metabolic pathways in an expeditious way. Conventional platforms utilizing single electrodes, or electrochemical cells, and colorimetric detection suffer from low sensitivity and low throughput. Moreover, they require bulky equipment for readout and fluid handling. Moving towards a nuanced miniaturized electrochemical detection, we propose individually addressable microwells used to monitor electron flux from EET-capable bacteria with the ability to screen a large number of electroactive bacteria for various applications. Materials and method : The device is simple and fabricated with cost-effective electrodes. Carbon felt is used as the working electrode to improve bacterial entrapment and assist in capturing maximum electrons donated by the electroactive bacteria. Silver-silver chloride ink (Ag/AgCl) as the reference electrode will help maintain the potential of with respect to the working electrode. Conductive carbon ink as the counter electrode will promote current collection. The proposed device has the elements of a traditional three electrode system arranged in two different planes resulting in a 3D configuration of electrodes. The reference and counter electrode are on the bottom plane with acrylic wells housed right above each electrode pair, while the working electrode is used in the cross-bar architecture from the top plane as shown in Figure 1(a). The fabrication steps are illustrated in Figure 1(b). This system can be scaled to have 10000 microwells on a single platform with individual addressability of each micro-well array. With this layout, connections from the innermost wells can be drawn effortlessly without any signal damping from the surrounding wells. As a proof of concept, we have fabricated a 9 by 9 array (20cm by 20 cm) as shown in Figure 1(a). Five strains of Shewanella oneidensis MR-1, the wild type organism and four modified strains overexpressing variants of MtrA (unmodified MtrA, IV-205, IV-261 and an empty vector), were screened for their current producing capacity [1]. Results:A bacterial load of OD600= 0.065 was sufficient to give a reliable current signal. For each strain, the working electrode was biased at 0.205 V with respect to the reference electrode (Ag/AgCl), and the resulting chronoamperometry signal was recorded as shown in Figure 1(c). The values obtained helped identify the current-producing capacity of each mutant. Among them, the highest peak current was given by mtr A+ (20 μA), and IV – 261 gave a low peak current (2 μA) within 3 minutes, validating the difference in the genetic make-up and EET capabilities. Technical and biological replicates were also conducted for all the 5 strains. The average standard deviation for the technical and biological replicates (n=3, OD600=0.065) was 0.09 μA and 0.56 μA respectively. A similar current trend for the same set of strains was obtained by Ian et al., [1] using a traditional bioelectrochemical system, thus validating our platform’s functionality and integrity. This system allows for parallel screening of wild type and mutant variations of multiple electroactive bacteria as demonstrated. The high throughput feature enabled by this device can also find application to characterize mutants generated by directed evolution workflows. Additionally, mechanical and electrical multiplexing can further improve the electronic instrumentation and connections between the wells for parallel readout and will also minimize human intervention during the current measurements. Chronoamperometry measurements is an important technique to characterize EET. Thus, a low-cost system like ours will help do that in a shorter time frame with minimal bacterial inoculum and for a larger number of electroactive bacterial species. In conclusion, we aim to show that a 3D carbon felt platform is miniaturized, and can be scaled to understand and characterize EET from electroactive bacteria in a high throughput manner. References Ian J. Campbell, Joshua T. Atkinson, Matthew D. Carpenter, Dru Myerscough, Lin Su, Caroline M. Ajo-Franklin, and Jonathan J. Silberg Biochemistry 2022 61 (13), 1337-1350 Figure 1

Degradation and Protection Mechanisms of Platinum-Based Catalysts in Hydrogen-Bromine Flow Batteries

Cost-effective and large-scale electrical energy storage is pivotal in facilitating the assimilation of renewable energy sources like wind and solar, as well as enhancing the resilience of the future electricity grid. Hydrogen-Bromine flow battery (HBFB) technology is a candidate for a low cost and flexible system. Bromine is abundantly available on Earth. In addition, the reaction between bromine and bromide is characterized by rapid kinetic properties, thus no platinum group metals (PGMs) are required on the bromine side of the cell as a catalyst to sustain a high current density of >500 mA/cm2. Moreover, hydrogen-based flow batteries can be coupled with hydrogen pipelines & electrolyzers to boost the integration of new energy systems.However, the selection of bromine brings technical challenges that can limit the commercial deployment of such HBFB systems. We have proven a lifetime of more than 8,000 hours of continuous cycling at the lab scale. During this proof-of-concept validation, we found that bromine species (liquid) crosses through a dense proton exchange membrane to the hydrogen side of the cell. On this side, a Platinum-based catalyst layer is present to promote hydrogen oxidation-evolution reactions (HOR/HER). The crossover liquid interacts first with the catalyst layer before it crosses through the gas diffusion layer and exits the membrane electrode assembly (MEA). Chemical interactions between the crossover liquid and the catalyst can lead to catalyst migration, Ostwald ripening, or even permanent catalyst dissolution. This is a concern and must be addressed. The root of this concern is that the Platinum-based catalyst is highly reactive (high surface-active area respective to the loading, m2/g), and also the crossover bromine species are likely corrosive (highly acidic, pH <0, and contain polybromides). Therefore, chemical interaction cannot be fully avoided. Nevertheless, the cathodic protection reduces this interaction, which prolongs the lifetime of the electrochemical system. The cathodic protection consists of an applied positive potential and the presence of hydrogen gas on the catalyst nanoparticles. The catalyst degradation together with cathodic protection needs to be better understood and quantified to gain the confidence that the HBFB system fundamentally can last for more than 10 years of continuous operation. This confidence is essential to deliver a minimum viable product (MVP) of HBFB, e.g. on a 100 kW – 1 MW scale, to the market.To address the aforementioned scientific challenges, this work studies the liquid crossover phenomena and the interaction between the crossover liquid and platinum-based catalyst in depth. Liquid crossover rate, concentration, and bromine speciation from working electrochemical cells are quantified at different states of charge (SoCs) and different modes (charge or discharge). This information is used to set up further ex-situ experiments to understand and determine the chemical interaction between crossover liquid and catalyst. Electrochemical ex-situ tests for Pt dissolution measurement such as determination of the electrochemically active surface area (ECSA), are performed before and after soaking hydrogen electrodes in different concentrations of hydrogen bromide solutions that mimic the crossover liquid. These results are then combined with in-situ tests, where the catalyst dissolution rate is quantified in actual crossover liquid and electrolyte by the inductively coupled plasma (ICP) method. Finally, post-mortem analyses on the catalyst layer based on scanning electron microscopy (SEM), transmission electron microscopy (TEM), etc. will give quantitative and qualitative insights into the impact of cycling and liquid crossover on the catalyst performance, morphology, crystal structure, and chemical state of the catalyst.The goal of this work is to quantify the extrapolated lifetime of HBFB systems within a high confidence level. Then conclude if this technology is fundamentally sound and can be scaled up to an MVP to be deployed to the market. As a low cost energy storage solution, the HBFB’s lifetime should be at least 5 years and preferably more than 10 years to attract commercial attention. Moreover, the collective knowledge gained in this work about the catalyst degradation mechanisms will spark further ideas and guide the next generation of the system and its operating conditions to reduce the degradation rate. These presented ideas may also shine a light on catalyst degradation and protection mechanisms in other electrochemical applications that operate in corrosive conditions.Figure 1 Membrane electrode assembly architecture, incl. electrochemical reactions and species transport phenomena in the charge and discharge modes. Figure 1