SIH26172HardwareSmart Automation
₹1,50,000 Prize (₹75k Joint)
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Deadline: 20 September 2026
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Submitted Ideas: 0/500

Low Latency and Efficient Voice Activator for Edge Devices

Ministry / Organization: Indian Space Research Organisation(ISRO)
Department: Department of Space / Indian Space Research Organisation
Technical Complexity
8/10
Dataset Accessibility
7/10
36h Hackathon Viability
9/10
Step 0 • Zero-Jargon Layman Summary

“We are building an ultra-efficient voice assistant trigger that runs on tiny microcontrollers without needing the internet. When it hears a specific secret command word, it instantly wakes up and securely streams subsequent voice instructions to a remote cloud server.”

The DecodeX PS Decoder™

Deconstructed Problem Blueprint

Step 1

WHAT TO BUILD?

An embedded TinyML Keyword Spotting (KWS) firmware paired with a low-latency audio streaming daemon running on an edge microcontroller (like an ESP32 or Raspberry Pi Pico W).

Step 2

WHO IS IT FOR?

ISRO space scientists, field engineers, and mission control operators who require hands-free, low-power, offline voice activation for equipment and IoT setups.

Step 3

WHY DOES IT EXIST?

Relying entirely on cloud processing for voice assistants causes high latency, severe privacy risks, and excessive battery/bandwidth consumption, making edge wake-word detection essential.

Step 4

INPUT → PROCESS → OUTPUT ARCHITECTURE PIPELINE

01 • Inputs & Telemetry

Continuous real-time audio feed from an I2S digital microphone (e.g., INMP441) capturing ambient sound.

02 • Processing & AI Core

Audio framing, Mel-Frequency Cepstral Coefficients (MFCC) feature extraction, inference via a quantized TinyML model (<256KB RAM footprint), followed by packetization and UDP/WebSocket streaming upon keyword confirmation.

03 • Actionable Deliverables

An immediate hardware interrupt trigger and a low-latency compressed audio stream directed to a remote Automated Speech Recognition (ASR) server.

Step 5

CONSTRAINTS

  • Strict memory footprint: Under 256KB of RAM available on the target microcontroller.
  • Low CPU usage: Under 10% utilization during idle continuous listening mode.
  • No proprietary SDKs or pre-trained generic wake words ('Hey Google', 'Alexa'); must train on a custom keyword.
  • Open-source frameworks only (TensorFlow Lite for Microcontrollers or PyTorch Mobile).
Step 6

JURY METRICS

  • Model RAM and Flash memory footprint
  • Idle CPU utilization percentage
  • True-positive keyword detection accuracy with near-zero false-positive rates
  • Latency delta between keyword ending and cloud ASR reception
Step 7

CORE BOTTLENECK

Balancing high keyword detection accuracy with extremely strict RAM (<256KB) and low idle CPU (<10%) limits on resource-constrained microcontrollers without triggering false positives from background noise.

Why You Should Choose This PS (Pros)

  • Extremely clear problem scope with precise, measurable evaluation metrics.
  • Hardware track solutions with live physical demos always stand out to judges.
  • Direct relevance to space tech automation, IoT, and defense-grade edge computing.

Challenges & Risks to Watch (Cons)

  • Requires actual hardware setup (ESP32/Raspberry Pi + microphone) during presentation, which can fail unexpectedly.
  • Training and quantizing custom acoustic models from scratch requires dataset collection and signal processing expertise.
Hackathon Blueprint

Recommended Tech Stack & Grand Finale Features

Frontend & Mobile
React.js dashboard for monitoring connected edge nodes and cloud ASR transcription output
Backend & APIs
Python FastAPI for the cloud ASR and streaming serverWebSockets for real-time low-latency audio packet transmission
AI / ML & Models
TensorFlow Lite for Microcontrollers (TFLite Micro)Custom lightweight Depthwise Separable CNN or MicroSpeech architectureOpenAI Whisper (tiny/base) or Vosk on the cloud ASR side
Database & Cloud
SQLite for logging device telemetry and command history

Killer Features to Impress the SIH Jury

Dynamic Noise Adaptation: On-device background noise profiling that auto-adjusts audio threshold gates.
Zero-Loss Pre-Roll Buffer: Circular buffer capturing audio 500ms *before* the keyword ends so no initial syllable is clipped.
Acoustic Fingerprint Validation: Cryptographic token validation sent alongside the audio stream to prevent spoofing attacks.
View Official SIH 2026 Portal Raw Text
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Background As voice-controlled IoT proliferate, processing everything in the cloud is too costly, privacy-invasive, and slow. The future belongs to hybrid architectures where the edge handles the initial 'wake-up' and the cloud handles the heavy lifting.

Description Build an ultra-lightweight, highly accurate keyword spotting (KWS) model that runs locally on a low-power device. Upon detecting the keyword, the system must instantly and efficiently stream the subsequent audio to a remote Automated Speech Recognition (ASR) server with minimal data overhead and latency.

Key Metrics for Evaluation

•Efficiency: Model size (RAM/Flash footprint) and CPU usage during idle listening.
•Accuracy: High true-positive rate for the keyword with near-zero false activations.
•Latency: The time delta between the keyword ending and the cloud ASR receiving the audio stream.

Software & Framework Restrictions

•Open-Source Only: The use of proprietary, closed-source, or commercial voice-activation SDKs is strictly prohibited.
•Allowed Frameworks: Teams must build their keyword spotting (KWS) pipelines using open-source machine learning and TinyML frameworks. Recommended tools include TensorFlow Lite for Microcontrollers, PyTorch Mobile or similar.
•No Pre-Trained Global Keywords: Teams cannot use models pre-trained on generic smart-assistant keywords like 'Hey Google' or 'Alexa'. They need to train on a custom key word.

Expected Solution Teams are expected to deliver a robust, deployable system architecture. A successful submission must strictly satisfy the following technical boundaries:

•Hardware & Runtime Environment: The edge software application must run smoothly within an environment restricted to less than 256KB of RAM and consume under 10% CPU utilization while idling in continuous listening mode. Heavy or uncompressed pre-trained transformers are disqualified. Solutions will be formally evaluated on physical low-power microcontrollers (e.g., Raspberry Pi or ESP32).
•Model should work for the given custom key word.