# Battery drain analysis - extract mV readings per device per session # E:/Watcherr/07-testing/battery-testing/WatcherrPro Battery life.xlsx import openpyxl, pandas as pd wb = openpyxl.load_workbook("WatcherrPro Battery life.xlsx", data_only=True) ws = wb["Battery Test"] # Collect (date, time, device_mac, battery_pct) rows records = [] for row in ws.iter_rows(min_row=4, values_only=True): date, time, batt_pct, notes = row[1], row[2], row[3], row[4] if batt_pct is not None: records.append({"date": date, "time": time, "battery": batt_pct}) df = pd.DataFrame(records) df["datetime"] = pd.to_datetime(df["date"].astype(str) + " " + df["time"].astype(str)) drain_per_day = df.groupby(df["datetime"].dt.date)["battery"].agg(["first","last"]) drain_per_day["drain"] = drain_per_day["first"] - drain_per_day["last"] print(drain_per_day)

HardwareMobile

Hardware & Firmware QA - IoT Wearable Platform

QA gating across 23 test cycles, from bring-up to production release.

Test Reports Filed

97.4%

Pass Rate

3 Devices

Watcherr Lite · Pro · Gateway

Tech Stack

Test PlanningExcelPythonAndroid E2EBattery AnalysisRisk Assessment

The problem

If an elderly resident presses their distress button and the wristband fails to send the alarm, that's a patient safety incident - not just a bug. The firmware had to be rigorously tested before every release across three different device versions, and battery life had to be tracked separately because each firmware update could silently drain the battery faster.

The challenge

IoT wearable firmware for a care-home safety device has zero tolerance for missed alarms or false negatives - a failure to transmit a distress signal in a real emergency is a patient safety incident. At the same time, the device ships to non-technical care staff who cannot diagnose or work around bugs in the field. QA had to catch defects before every release, validate that behaviour matched the firmware spec across three distinct hardware variants (B7, B8, W7), and maintain a structured test record trail for regulatory purposes. Battery life also had to be validated continuously as firmware changes to the BLE stack, sleep modes, and alarm logic affected drain rates unpredictably.

QA Process & Test Structure

Full test reports and master test plan available upon request

QA was structured around three artefacts: a Master Device Test Plan covering 49 hardware test cases across all product lines (firmware OTA, BLE reconnection, alarm trigger, battery drain, LED, geofencing, fall detection), a Software Test Plan covering 103 app and dashboard cases (Android/iOS install, login flows, alert flows, dashboard sync), and per-release Test Reports filed in Excel tracking firmware version, hardware variant, tester, pass/fail per case, and bug severity. Battery testing ran in parallel: devices were held in controlled conditions (within and outside gateway range) with periodic manual alerts, reading battery percentage and mV at regular intervals across multiple-day sessions to produce drain curves per firmware version. An Android E2E automation suite covered the companion app's critical alert and provisioning flows.

Results

Across 23 test cycles spanning Watcherr Lite v1.0.4 through v1.0.32 and Watcherr Pro, 344 test cases passed against 9 failures - a 97.4% pass rate. Each failure was documented with severity, reproduction steps, and linked to the firmware fix. Battery testing across 5+ devices in both gateway-proximity and out-of-range conditions established baseline drain curves used to validate the firmware's adaptive duty-cycling implementation. The structured test trail provided a formal QA record for regulatory and partner validation reviews. Release gating reduced post-deployment field issues across care-home deployments in Belgium and the Netherlands. Watcherr subsequently rebranded as ixicare; the device family and platform continue under that brand.

Gallery & Demos

Gateway Dashboard - Monitoring Interface

Control center for care home staff showing all wearable devices, connection status, and real-time alert feed.

Installation Guide

Setup documentation showing how to pair devices, configure gateway, and deploy system across care facility.

Device Alarm Activation

Visual demonstration of resident activating device alarm when assistance is needed.

Click any image or video to expand · ← → keys navigate

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