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Freelance IMU Data Analyst — Ground Truth Validation & Filter Design (BLE Wearable / MEMS IMU) Engagement: Freelance / Contract (remote) Duration: 3–4 weeks Budget: open to fixed-price or hourly proposals Start: immediate ──────────────────────────────────────── ABOUT THE PROJECT ──────────────────────────────────────── We are developing a Bluetooth-LE wearable that streams 9-DOF IMU data over BLE in a fixed 68-byte packet. The firmware runs in two parallel configurations that must produce equivalent output: • Configuration A — Bosch BHI260AP: 6-axis IMU + magnetometer with on-chip sensor fusion (BHY2 virtual sensor engine), sampled at 17 Hz. • Configuration B — Bosch BMI323: 6-axis IMU only, with a Mahony filter running on the MCU for orientation, gravity, and linear acceleration, sampled at 25 Hz. Both configurations transmit the same five sensor blocks per packet: accelerometer (g), gyroscope (dps), linear acceleration (g), gravity vector (g), and orientation as Euler angles (yaw / pitch / roll, in degrees). We need an experienced IMU specialist for two related deliverables: 1. Independently VALIDATE that the data we transmit is correct — from raw int16 sensor output, through scaling and sensor fusion, to the final float32 values delivered to the host. 2. DESIGN AND ANALYSE the digital filters and fusion-filter tuning used in our pipeline — characterise sensor noise, recommend pre-filtering, and tune (or propose alternatives to) the on-MCU Mahony filter for Config B so that its output matches the BHI260AP fused output as closely as possible. ──────────────────────────────────────── SCOPE OF WORK ──────────────────────────────────────── You will be provided with a detailed validation reference document, BLE packet captures from both firmware configurations, and the hardware unit shipped to you (or remote test-bench access — to be agreed). --- PART 1: VALIDATION --- 1. Decode the 68-byte BLE packet and verify that all 60 float32 fields parse cleanly (no NaN/Inf, correct endianness, correct field order). 2. Verify scaling of raw int16 data against documented LSB constants (accel 0.000244 g/LSB, gyro 0.061 dps/LSB, orientation 0.00549°/LSB for Config A). 3. Run static / at-rest tests — confirm gravity reads ~1 g on the up-axis, gyro reads ~0 dps, linear accel reads ~0 g, and gravity vector magnitude ≈ 1 g. 4. Run dynamic tests — controlled tilts (90° on X / Y), 360° yaw rotation, free-fall drop, and known-rate angular velocity if a rate table is available. 5. Cross-validate Configuration A vs. Configuration B for the same motion sequences. 6. Verify calibration state for Config A (per-sensor accuracy bytes must reach 3 before data is considered trustworthy). --- PART 2: FILTER DESIGN & ANALYSIS --- 7. Characterise raw sensor noise — Allan variance / PSD analysis of accelerometer and gyroscope at the operating ODR; identify bias instability, random walk, and any structured noise (e.g. mains pickup, mechanical resonance). 8. Pre-filter design — propose and prototype digital filters for the raw IMU stream (typically low-pass for accel noise, high-pass / notch for gyro drift and structured noise). Provide filter coefficients, magnitude/phase plots, group-delay analysis, and quantify SNR improvement. 9. Mahony filter tuning (Config B) — tune Kp and Ki gains for our use-case, characterise convergence time, steady-state error, and yaw-drift rate. Quantify trade-offs between responsiveness and noise rejection. 10. Quaternion-norm stability check — confirm |q| stays within tolerance over long runs; flag any normalisation issues. 11. Comparative analysis — benchmark our Mahony output against at least one alternative (e.g. Madgwick, complementary filter, lightweight EKF) on the same recorded data; recommend whether to keep, retune, or replace. 12. Cross-config alignment — quantify the residual error between Config A (BHI260AP fusion) and Config B (Mahony) outputs after your tuning, and document the remaining gap. 13. Document findings with pass/fail against documented criteria, and root-cause any deviations. ──────────────────────────────────────── REQUIRED SKILLS & BACKGROUND ──────────────────────────────────────── • 3+ years hands-on experience with MEMS IMUs (Bosch, ST, InvenSense, or similar) • Strong understanding of sensor fusion: complementary / Mahony / Madgwick / EKF, quaternion math, Euler angle conventions • Solid DSP background: FIR/IIR filter design, Allan variance, PSD analysis, group delay, fixed-point vs. floating-point trade-offs • Experience tuning fusion-filter gains for embedded targets (memory and CPU constrained) • Comfortable with raw int16 sensor data, scaling, and BLE packet parsing • Proficient in Python (NumPy, SciPy, Pandas, Matplotlib) for analysis, filter design, and plotting • Experience comparing IMU output against a reference (rate table, optical tracking, surveyed reference IMU, or calibrated turntable) • Bonus: prior experience with Bosch BHI260AP or BMI323, BLE sniffing tools (Wireshark + nRF Sniffer / TI sniffer), or embedded firmware debugging ──────────────────────────────────────── DELIVERABLES ──────────────────────────────────────── 1. Validation report (PDF) — pass/fail table per test, with measured values, deviations, and plots. 2. Filter design report (PDF) — noise characterisation results, proposed filter topologies, coefficients, frequency-response plots, Mahony tuning recommendations, and comparative benchmarks against alternative fusion algorithms. 3. Python scripts / notebooks used for decoding, analysis, filter design, and benchmarking (well-commented, runnable on a fresh environment). 4. Raw and decoded data files from each test run. 5. Drop-in C/C++ reference implementation (or pseudocode) for any new filter to be ported to the MCU. 6. Recommendations for any failures or out-of-spec behaviour, with proposed root cause and suggested fixes. 7. Wrap-up call (~1 hour) to walk us through findings. ──────────────────────────────────────── HOW TO APPLY ──────────────────────────────────────── Please include in your proposal: • A short note on your relevant IMU validation and filter-design experience (links to past work / writeups appreciated) • The reference equipment you have access to (rate table, optical mocap, reference IMU, etc.) • Your availability and proposed timeline • A fixed-price quote OR hourly rate with estimated hours, ideally split across Part 1 (validation) and Part 2 (filter design) • Any clarifying questions about the project We will share the full validation reference document and a sample BLE capture with shortlisted candidates under a brief NDA. Looking forward to working with someone who can be rigorous about the math and methodical about the testing.
Project ID: 40411045
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17 freelancers are bidding on average ₹24,671 INR for this job

With a rich background in Electrical Engineering with emphasis on firmware development, PCB design, and IoT product engineering, I guarantee a profound understanding of your project's core requirements. As an experienced professional, I have worked extensively with microcontrollers like STM32, ESP32, and Nordic nRF52/nRF53 - all highly relevant to your BLE wearable undertaking. My familiarity with software like C/C++, wireless stacks including BLE and Wi-Fi, and real-time operating systems is exceptional, having leveraged them for numerous projects in my career. On top of possessing the right skill sets for your project, my approach to full product development aligns strongly with your needs. From system architecture to PCB Design and Firmware Development -- I take a comprehensive view that includes aspects such as data analysis and control. In line with this, my expertise in AI and Machine Learning extends to intelligent algorithms for edge devices and data analysis—skills that would immensely help in the filter design and analysis process you require.
₹75,000 INR in 15 days
7.1
7.1

Hi there, I carefully read your project, and I can help you validate and optimize your IMU pipeline end-to-end—from raw sensor decoding to fusion accuracy and filter tuning . I’m Samuel Tshibangu, a mechatronics engineer with strong experience in embedded systems, sensor integration, and signal processing. I’ve worked with IMU-based systems, BLE data pipelines, and real-time filtering, so I can efficiently analyse your data integrity, validate scaling, and tune your fusion pipeline for stable and accurate outputs. I can handle both validation (packet decoding, scaling, static/dynamic tests, cross-config comparison) and filter design (noise characterization, pre-filtering, Mahony tuning, and benchmarking against alternatives), delivering clear reports and usable scripts. I’m confident I can deliver a structured, methodical analysis within your timeline. Feel free to send me a message. Best regards, Samuel Tshibangu
₹25,000 INR in 1 day
4.5
4.5

As an experienced Full-Stack Developer, my skillset extends beyond just coding web or mobile apps. I have a deep understanding of BLE technology which is crucial for your project. I have successfully built and integrated Bluetooth features into various applications, making me confident in my ability to validate the IMU data from your BLE wearable with precision. My Python expertise has prepared me well for parsing and validating complex data structures like the 68-byte BLE packet you have, ensuring that all fields parse properly and are within acceptable parameters. Having developed several AI-powered solutions involving motion sensing, I understand the nuances involved in such algorithms with respect to noise filtering and accurate readings. This makes me well-equipped to design digital filters for your raw IMU data streams, characterizing sensor noise, outputting SNR data and providing real-time validation values effectively benchmarking against industry-standard alternatives such as Madgwick for optimal resutls. With my proactive communication style, you can expect daily updates on progress along with realistic timelines; no radio silence or any unexplained gaps! Having worked with global clients before, I am comfortable working remotely and creating a perfect experience even across time zones. Invest in my skills and redefine the accuracy of your Bluetooth wearable project. Let's get started!
₹35,000 INR in 7 days
4.2
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I am an expert statistician, Research Writer, and data analyst with more than eight years of experience. I have full command of Excel analysis, SPSS, STATA, R LANGUAGE, AND PYTHON. I am an expert in creating time series prediction models, working with survey data, conducting marketing analysis, building estimators, and medical analysis. I am a perfect match for your project share other details of the work so I can start working on your project. Will complete task on time.
₹12,500 INR in 1 day
4.1
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Hi, I am an IITian , worked at fortune 500 companies. I will make it a reality for you. With 7+ years of experience I will analyze the provided BLE wearable IMU data, identify potential errors or inconsistencies, and develop a ground truth validation plan to ensure equivalent output between Configurations A and B using statistical methods and sensor calibration techniques. Kindly click on the chat button so we can discuss and get started. Will share you my prior projects done and my resume too. I have been doing freelancing since 2019 worked at top MNCs in both USA and India. Lets connect
₹12,500 INR in 7 days
2.7
2.7

I have hands-on BLE wearable and MEMS IMU experience — including a shipped wearable with nRF BLE, 3-axis IMU, and quaternion-based orientation. Python data decoding, LSB scaling verification, and sensor fusion validation are work I've done before. I will cover all 8 scope items: packet decode (60 float32 fields, endianness, NaN/Inf), LSB scaling verification, static + dynamic tests, Config A vs B cross-validation, Mahony filter quaternion norm + yaw drift, and BHI260AP calibration accuracy byte check (threshold: 3). Reference equipment: IMU reference board + calibrated turntable. No rate table — being upfront. Delivery in 2 days: PDF report, Python notebooks, raw/decoded data files, wrap-up call. Please share the sample BLE capture so I can verify packet parsing before we start.
₹12,500 INR in 3 days
2.2
2.2

With my extensive experience in handling MEMS IMUs, specifically from Bosch, ST, InvenSense, alongside strong comprehension of sensor fusion algorithms such as complementary / Mahony / Madgwick / EKF and quaternion math, I am well-positioned to take up your project. Python proficiency allows me to comfortably work with int16 sensor data, scaling, and BLE packet parsing for data analysis using the popular data science libraries like NumPy, Pandas and Matplotlib. My prior exposure validating IMU outputs against reference systems aligns perfectly with your requirements. Be it calibrated turntables or rate tables for known angular velocities or employing optical tracking or surveyed reference IMUs - I have adopted various techniques to ensure precise validation hence minimizing discrepancies. Lastly, my vast knowledge includes debugging embedded firmware which could prove useful in identifying and resolving any intermittent issues that may arise in Bosch BHI260AP or BMI323 aiding uninterrupted evaluation of Configuration A vs Configuration B. This multi-faceted approach ensures a comprehensive understanding pivotal for successful completion of this project within your required timeframe.
₹12,500 INR in 7 days
1.9
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I will validate your 9-DOF IMU pipeline end-to-end using Python (NumPy, Pandas, Matplotlib), decoding BLE packets, verifying float32 parsing, endianness, and scaling against LSB constants. I’ll conduct static/dynamic tests, compare Config A (BHI260AP) vs Config B (BMI323 + Mahony), and assess quaternion stability, drift, and calibration states. Deliverables include detailed validation report, plots, reproducible scripts, and root-cause analysis with corrective recommendations, ensuring mathematically rigorous and test-driven verification. NovaEra Solutions
₹20,000 INR in 7 days
0.0
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Hi, I have worked with BLE both software and hardware in a low power design and implement sensors fusion, I have implemented firmware in Zephyr RTOS , also I have worked on DSP and digital filter like kalman filter to get most reliable data from IMU sensors.
₹25,000 INR in 7 days
0.0
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Hi, your project caught my attention because matching BLE 9 DOF IMU output from BHI260AP fusion and BMI323 with MCU Mahony is exactly the kind of sensor validation and DSP work I enjoy. Recently I built a Python validation pipeline for a wearable motion tracker that decoded BLE IMU packets, checked int16 scaling, compared gravity, linear accel, gyro, and Euler output, and tuned fusion gains against a reference IMU. The hardest part was yaw drift and packet timing mismatch. I first tried comparing Euler angles frame by frame, but it gave false errors when sample rates differed, so I switched to quaternion based alignment with NumPy, SciPy, Pandas, and PSD plus Allan analysis, because it handles wraparound and timing better than plain angle checks. For your Phase 1, I would build a clean decoder first, then run static and motion tests with pass fail plots, design low pass or notch filters with clear delay checks, and tune Mahony against BHI260AP while also testing Madgwick or a light complementary filter. Do you already have a trusted motion reference for the dynamic tests, such as a rate table, calibrated turntable, optical tracking, or should I plan the comparison mainly against the BHI260AP output? I can review the reference document and sample BLE capture under NDA this week, then map the tests, scripts, reports, and C style filter notes. Best, adam
₹12,500 INR in 6 days
0.0
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Looking for reliable and high-quality software development? You're in the right place. I specialize in building scalable, efficient, and user-friendly applications tailored to your specific needs. Whether you're a startup, business, or individual, I can turn your ideas into fully functional software solutions. What I Offer: Custom Web Application Development (Frontend & Backend) Mobile App Development (Android & iOS) Desktop Software Development API Development & Integration Bug Fixing & Performance Optimization Database Design & Management UI/UX Implementation Technologies I Work With: JavaScript (React, Node.js) Python (Django, Flask) Java / Kotlin C# (.NET) SQL & NoSQL Databases RESTful APIs Why Choose Me: Clean, maintainable, and scalable code On-time delivery Clear communication throughout the project Customized solutions based on your requirements Post-delivery support How It Works: Share your project requirements Get a tailored plan and timeline Development & regular updates Testing and final delivery Note: Please contact me before placing an order to discuss your project details and ensure the best results. Let’s build something great together.
₹25,000 INR in 7 days
0.0
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Ross here from Arasaka Systems, hope you’re doing well. I recently completed a similar IMU data validation and filter design project, ensuring clean, professional, and high-performing sensor fusion outputs. Your need for thorough validation of BLE 9-DOF IMU data and precise Mahony filter tuning for Config B shows a commitment to integrated, quality solutions. I ran Arasaka Systems from Cape Town, South Africa, focusing on embedded sensor analytics, and I’m now expanding internationally to bring that expertise to your project. With 3+ years in MEMS IMUs, DSP filter design, and Python-based analysis, I offer comprehensive, methodical validation and filter optimisation. I need: 3 weeks (21 days) the cost will be: $310 Im just wrapping up a system enhancement program, so i am available I appreciate you looking over my proposal, it would be a pleasure to be of assistance. Regards, Ross, Arasaka Systems
₹29,400 INR in 21 days
0.0
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Hi, I have hands-on experience with MEMS IMU integration, sensor fusion, and embedded systems, and I can handle both parts of this project. I have worked with Bosch and ST Micro IMUs in BLE wearable designs, including raw sensor data parsing, scaling, and fusion filter implementation. I am comfortable with Mahony and Madgwick filters, quaternion math, and Allan variance analysis. For Part 1, I will decode and validate your 68-byte BLE packets, verify scaling constants, and run static and dynamic tests across both Config A and Config B to confirm output correctness. For Part 2, I will characterise sensor noise using PSD and Allan variance, design pre-filters, tune the Mahony gains for Config B, and benchmark against alternatives such as Madgwick and complementary filter on the same recorded data. Deliverables I will provide: - Validation report with pass/fail table and plots - Filter design report with noise analysis, coefficients, and Mahony tuning recommendations - Well-commented Python notebooks for decoding, analysis, and benchmarking - C/C++ reference implementation for any new filter - Wrap-up call to walk through findings I am available to start immediately. Happy to sign an NDA and review the sample BLE capture before confirming the timeline and fixed-price quote.(3 DAYS) Thank you.
₹12,500 INR in 7 days
0.0
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We at HardFault have strong experience with MEMS IMU validation and sensor-fusion pipelines, including devices like Bosch BHI260AP and Bosch BMI323. We can handle your requirement end-to-end—from BLE packet decoding and raw data validation to noise analysis, filter design, and Mahony tuning—ensuring both configurations align closely with accurate, stable outputs. Our expert team will deliver clear validation reports, optimized filter designs, and ready-to-use Python + embedded implementations, making it easy for your firmware team to integrate improvements. Do you already have any reference setup for ground-truth comparison, or should we define the validation approach based on controlled motion tests?
₹40,000 INR in 7 days
2.3
2.3

I am very interested in your IMU validation and filter design project. With over 4 years of hands-on experience in embedded systems and drone flight controller development, I have worked extensively with MEMS IMUs, sensor fusion algorithms, and real-time data processing—making this project highly aligned with my expertise. In my current role as a Lead Engineer in an R&D environment, I design and develop firmware for drone flight control systems, where IMU data accuracy and fusion reliability are critical. I have practical experience working with accelerometers, gyroscopes, and magnetometers, including calibration, scaling, and validation of raw sensor data. I have also implemented and tuned sensor fusion algorithms such as complementary and Mahony filters for stable attitude estimation. Additionally, I have significant experience working with Nordic Semiconductor (nRF) BLE SoCs, including BLE data streaming, packet structuring, and decoding—directly relevant to your 68-byte packet validation requirements. Relevant Experience 1. Firmware development for drone flight controllers with real-time IMU processing 2. Implementation and tuning of Mahony/complementary filters for orientation estimation 3. Strong understanding of quaternion math, Euler angle conversions, and coordinate systems 4. Experience handling raw int16 IMU data, scaling, and sensor calibration 5. BLE communication using nRF series (data acquisition, packet parsing, debugging)
₹20,000 INR in 22 days
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