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arXiv · 2208.01201

Analog Gated Recurrent Neural Network for Detecting Chewing Events

Kofi Odame·Maria Nyamukuru·Mohsen Shahghasemi·Shengjie Bi·David Kotz
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Abstract

We present a novel gated recurrent neural network to detect when a person is chewing on food. We implemented the neural network as a custom analog integrated circuit in a 0.18 um CMOS technology. The neural network was trained on 6.4 hours of data collected from a contact microphone that was mounted on volunteers' mastoid bones. When tested on 1.6 hours of previously-unseen data, the neural network identified chewing events at a 24-second time resolution. It achieved a recall of 91% and an F1-score of 94% while consuming 1.1 uW of power. A system for detecting whole eating episodes -- like meals and snacks -- that is based on the novel analog neural network consumes an estimated 18.8uW of power.

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Kofi Odame, Maria Nyamukuru, Mohsen Shahghasemi, Shengjie Bi, David Kotz. 2022-08-02. Analog Gated Recurrent Neural Network for Detecting Chewing Events. https://arxiv.org/abs/2208.01201

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