Efficient Pipeline Design for Real-Time RNN-based Anomaly Detection in Embedded Edge AI Systems

This master's thesis explores and evaluates how to design efficient edge AI pipelines for anomaly detection. The deep learning architecture used was a recurrent neural network (RNN) autoencoder, capable of reconstructing and detecting abnormal data points, suitable for resource-constrained embedded systems. It investigates how such models can be executed on the ESP32-P4 MCU using Zig as the primary programming language. The main goals are to evaluate model accuracy, latency (throughput), and memory footprint for real-time use cases. The proposed solution uses a compact Recurrent Neural Network autoencoder trained on time-series data from the SMAP and MSL datasets to detect anomalies in univariate signals. The system performs inference without any dynamic memory allocation, using compile-time Matrix and Layer types built from scratch, and compiles them into the same trained model used in PyTorch. Benchmarking on the ESP32-P4 showed a latency way below 2 ms per window, with a peak throughput (latency) of approximately 786 predictions per second for the final optimized build. The model generalization achieved an F1-score of 0.6075 and an AUROC of 0.667 on the E-3 channel (dataset), while maintaining a total memory footprint of ≈3.875 KB and an average energy consumption of 0.772 mJ per inference. The result demonstrates that deep learning models can run deterministically on low-powered hardware using Zig's safety-aware programming model. Moreover, this thesis contributes to a reproducible toolchain, a Zig runtime for RNN inference, and a benchmark methodology that links accuracy, latency, and memory usage in edge AI embedded anomaly detection.