pi-car-companion/notes/first-test-drive.md

title, aliases, project, type, status, date, source, tags

title	aliases	project	type	status	date	source	tags
Pi Car Companion - First Test Drive	First Test Drive Notes	Pi Car Companion	field-notes	Follow-up required	Unknown	https://git.molberg.cloud/alex/pi-car-companion	pi-car-companion mg4 first-test-drive telemetry android networking

Pi Car Companion: First Test Drive

[!info] Purpose Notes from the first real-world test drive of Pi Car Companion. This document is a pickup point for later project work. It records observations and questions, not an instruction to implement every item immediately.

Scope and handling

[!important] Do not over-implement The larger investigations and feature requests below must not be started automatically. They are notes for later pickup.

Small, explicit, low-risk fixes for a specific listed problem may be made without separate approval. The inverted wheel animation in the web UI is an example of this kind of fix.

Power, networking, ADB reliability, telemetry accuracy, Android Auto, battery-service access, new phone-app features, shell access, power controls, and map-provider changes require separate investigation and approval before implementation.

Quick overview

Area	Observation	Status
Power	Raspberry Pi desktop showed a low-voltage warning while powered by the power bank	Investigate later
ADB	Connection dropped during the drive	Investigate later
Speed	Readings were a few km/h low	Investigate later
Peak speed	Trip report missed the observed top speed	Investigate later
Wi-Fi	Hotspot disconnected repeatedly	Investigate later
Phone GPS	GPS should stop when the Pi is unreachable	Feature request
Phone app	More controls and trip features requested	Feature request
Trip map	OpenStreetMap Referer handling or another map solution needed	Investigate later
Android Auto	Repeated disconnects and unstable connection	Investigate later
Battery	Battery data could not be read	Investigate later
Web UI	Wheel animation direction is inverted	Simple fix candidate
Phone app	Wheel animation requested	Feature request

Detailed notes

Raspberry Pi low-voltage warning while using the power bank

• The Raspberry Pi showed a desktop-environment notification saying: "Low voltage. Please check power supply."
• This happened while the Pi was running from the power bank.
• The power bank itself did not report the warning.
• Possible relation to the Pi, the AWUS1900, Wi-Fi instability, or other USB hardware is unknown.

Follow-up question: Is the power bank providing stable and sufficient power to the Raspberry Pi under load?

ADB connection drops

• The ADB connection dropped during the test drive.
• The problem was visible in the phone app and in the trip GPS data.

Follow-up questions:

• Was the ADB connection drop caused by power, Wi-Fi, USB, or the infotainment system?
• How does the dropout affect trip recording and phone-app state?

Speed and peak-speed data

• Speed was a few km/h off:
  • Approximately 65 km/h in reality.
  • Approximately 63-64 km/h reported.
• Peak speed may not be logged quickly enough:
  • Real top speed: 126 km/h.
  • Trip report: 116 km/h.
  • Phone app: 124 km/h.

Follow-up questions:

• Is the difference caused by sampling interval, timestamp alignment, GPS smoothing, or trip aggregation?
• Why was the phone-app value closer to the observed top speed than the trip report?

Wi-Fi hotspot instability

• The Wi-Fi hotspot disconnected constantly.
• A power-supply problem is suspected as one possible cause.
• The AWUS1900 may be rebooting because of insufficient power.

Follow-up questions:

• Does the AWUS1900 reset when the Raspberry Pi reports low voltage while powered by the power bank?
• Do Wi-Fi disconnects occur at the same time as ADB and Android Auto disconnects?
• Is the built-in Pi Wi-Fi adapter still stable when the AWUS1900 drops?

Phone-app behavior when the Pi is unreachable

The phone app should eventually be able to:

• Stop sending GPS data when there is no connection to the Pi.
• Hide its notification while disconnected.
• Enter a low-power sleep state until the Pi connection returns.
• Resume GPS updates and the notification after reconnecting.

[!note] Scope This is a behavior change in the Android companion, not a simple documentation or UI correction. Leave it as a later feature unless explicitly picked up.

Additional phone-app features requested

• Edit shortcut apps.
• Possibly provide shell access.
• Reboot or power off the Pi.
• View trip data.
• Add a Settings page containing:
  • Hotspot settings.
  • Software update controls.

[!warning] Safety and scope Shell access, reboot, and power-off are operational features with security and safety implications. Do not implement them from this note alone. Any future implementation must preserve the project's restricted, authenticated design.

Trip-report map

• The trip-report map needs a Referer header for OpenStreetMap requests.
• Consider an alternative map provider.
• Consider whether map data could be pre-baked into the Android app and web UI.

Follow-up questions:

• Can the existing map integration send the required header correctly?
• Would an alternative provider or offline map data better fit the local-first design?
• What attribution and licensing requirements would apply?

Android Auto disconnects

• Android Auto repeatedly disconnected.
• The connection was unstable.

Possible causes mentioned during the test:

• ADB instability.
• Wi-Fi interference.
• Bluetooth interference.
• Power instability.

No cause has been confirmed.

Battery telemetry unavailable

• Battery data could not be read during the test.

The cause is unknown. The UI should continue to show battery values as unavailable rather than substituting unrelated Android head-unit battery data.

Wheel animation

• The wheel animation is inverted in the web UI.
• The phone app should also receive a wheel animation.

[!tip] Simple fix candidate Correcting the direction of the existing web UI wheel animation is an explicitly listed, small UI fix and may be handled independently. Adding a new wheel animation to the phone app is a separate feature and should not be assumed to be included in that permission.

Later pickup checklist

Reliability investigation

• Investigate the low-voltage warning from the power bank.
• Determine whether the AWUS1900 is rebooting or losing power.
• Investigate ADB connection drops.
• Investigate repeated Wi-Fi hotspot disconnects.
• Investigate Android Auto disconnects and possible Wi-Fi/Bluetooth interference.

Telemetry investigation

• Review the small speed discrepancy.
• Review peak-speed sampling and trip aggregation.
• Investigate why battery data cannot be read.

Phone-app feature work

• Design disconnected GPS behavior.
• Consider shortcut editing.
• Consider trip data support.
• Consider a phone-app Settings page.
• Evaluate whether shell, reboot, and power-off controls are appropriate.
• Consider adding wheel animation to the phone app.

Map work

• Decide between fixing the OpenStreetMap request headers, using another provider, or supporting offline/pre-baked map data.

Explicitly allowed simple fix

• Correct the inverted wheel animation in the web UI.

English rewrite

• Raspberry Pi: The desktop environment showed a low-voltage warning saying, "Low voltage. Please check power supply." while the Pi was running from the power bank.
• ADB connection dropped.
  • This was visible in the phone app and in the trip GPS data.
• Speed was a few km/h off.
  • Approximately 65 km/h was shown as 63-64 km/h.
• Peak speed may not be logged quickly enough.
  • Real top speed: 126 km/h.
  • Trip report: 116 km/h.
  • Phone app: 124 km/h.
• The Wi-Fi hotspot disconnected constantly.
  • Could this be a power-supply problem?
  • Could the AWUS1900 be rebooting because of insufficient power?
• The phone app should stop sending GPS data when it has no connection to the Pi.
  • Hide the notification and enter a low-power sleep state until the Pi connection returns.
• The phone app needs more features.
  • Edit shortcut apps.
  • Shell access?
  • Reboot or power off the Pi.
  • Trip data.
  • Settings page:
    • Hotspot settings.
    • Software updates.
• The trip-report map needs a Referer header for OpenStreetMap.
  • Alternative map provider?
  • Could map data be pre-baked into the Android app and web UI?
• Android Auto repeatedly disconnected and had an unstable connection.
  • Was it caused by ADB?
  • Wi-Fi/Bluetooth interference?
• Battery data could not be read.
• The wheel animation is inverted in the web UI.
  • Add wheel animation to the phone app.

Original notes in Danish

• Raspberry Pi desktop environment showed a low-voltage warning ("Low voltage. Please check power supply") while running through the power bank
• ADB connection dropper ud
  • Ses på telefon app, og trip GPS data
• Speed er få km/h off (65 -> 63-64 km/h)
• Peak speed logges ikke hurtigt nok?
  • Ramte real 126 km/h top speed (trip siger 116 km/h)
  • Telefon app viste 124 km/h
• WiFi hotspot disconnecter konstant.
  • Power supply problem?
  • Måske fordi AWUS 1900 rebooter pga lav strøm?
• Telefon app skal kunne stoppe med gps data når ingen forbindelse til pi
  • skjul notifikation og gå i dvale indtil reconnect med pi
• Telefon app skal have flere features
  • edit shortcut apps
  • shell?
  • Reboot/power off pi
  • Trip data
  • Settings page
    • Hotspot settings
    • Software Update
• Trip report map skal have Referer header til openstreetmap.
  • Alternativ kort?
  • Prebaked ind i App og web ui?
• Android Auto blev ved med at disconnect og havde sporty connection
  • Skyldes ADB?
  • WiFi/Bluetooth interference?
• Battery data kan ikke læses
• Wheel animation er inverted på web ui
  • Tilføj wheel animation på telefon app

Related project

• Pi Car Companion
• Repository: alex/pi-car-companion

Changelog

• Added as a project note under notes/.
• Preserved the original Danish notes.
• Added a structured English rewrite.
• Marked broad work as later pickup and separated the simple web wheel-animation fix.

[!note] No implementation was made from this note.