We propose MiShape, a millimeter-wave (mmWave) wireless signal based imaging system that generates high-resolution human silhouettes and predicts 3D locations of body joints. The system can capture human motions in real-time under low light and low-visibility conditions. Unlike existing vision-based motion capture systems, MiShape is privacy non-invasive and can generalize to a wide range of motion tracking applications at-home. To overcome the challenges with low-resolution, specularity, and aliasing in images from Commercial-Off-The-Shelf (COTS) mmWave systems, MiShape designs deep learning models based on conditional Generative Adversarial Networks and incorporates the rules of human biomechanics. We have customized MiShape for gait monitoring, but the model is well adaptive to any tracking applications with limited fine-tuning samples. We experimentally evaluate MiShape with real data collected from a COTS mmWave system for 10 volunteers, with diverse ages, gender, height, and somatotype, performing different poses. Our experimental results demonstrate that MiShape delivers high-resolution silhouettes and accurate body poses on par with an existing vision-based system, and unlocks the potential of mmWave systems, such as 5G home wireless routers, for privacy-noninvasive healthcare applications.
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MiSleep: Human Sleep Posture Identification from Deep Learning Augmented Millimeter-Wave Wireless Systems
In this work, we proposeMiSleep, a deep learning augmented millimeter-wave (mmWave) wireless system to monitor human sleep posture by predicting the 3D location of the body joints of a person during sleep. Unlike existing vision- or wearable-based sleep monitoring systems,MiSleepis not privacy-invasive and does not require users to wear anything on their body.MiSleepleverages knowledge of human anatomical features and deep learning models to solve challenges in existing mmWave devices with low-resolution and aliased imaging, and specularity in signals.MiSleepbuilds the model by learning the relationship between mmWave reflected signals and body postures from thousands of existing samples. Since a practical sleep also involves sudden toss-turns, which could introduce errors in posture prediction,MiSleepdesigns a state machine based on the reflected signals to classify the sleeping states into rest or toss-turn, and predict the posture only during the rest states. We evaluateMiSleepwith real data collected from Commercial-Off-The-Shelf mmWave devices for 8 volunteers of diverse ages, genders, and heights performing different sleep postures. We observe thatMiSleepidentifies the toss-turn events start time and duration within 1.25 s and 1.7 s of the ground truth, respectively, and predicts the 3D location of body joints with a median error of 1.3 cm only and can perform even under the blankets, with accuracy on par with the existing vision-based system, unlocking the potential of mmWave systems for privacy-noninvasive at-home healthcare applications.
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- PAR ID:
- 10492330
- Publisher / Repository:
- ACM
- Date Published:
- Journal Name:
- ACM Transactions on Internet of Things
- ISSN:
- 2691-1914
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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