MotionEase

Vehicle Motion Cues for Windows | Built by KeepSimple.io

MotionEase draws subtle, animated reference dots around your screen edges to help reduce motion sickness when using a laptop in a moving vehicle. Inspired by Apple’s Vehicle Motion Cues, reimagined as a lightweight, portable Windows desktop app.

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How It Works

Motion sickness occurs when your eyes and inner ear disagree about movement. MotionEase places peripheral visual anchors around your screen that sway at 0.2 Hz – the exact frequency band where motion sickness peaks (Diels & Howarth, 2013). These dots give your visual system a stable reference frame, reducing the sensory conflict without interrupting your work.

The overlay is fully transparent and click-through – you work normally while the dots do their job in your peripheral vision.

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Download

MotionEase.exe – single portable file, no installation required.

Double-click and go. No Python, no dependencies, no setup.

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System Requirements

Requirement	Details
OS	Windows 10 (1809+) / Windows 11
Architecture	x86-64
Display	Single monitor (primary)
Permissions	No admin rights required
Size	~16 MB

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Modes

Mode	Key	Description
Drift (default)	Ctrl+Alt+3	Dots sway automatically at scientifically-relevant frequencies, simulating vehicle motion cues
Static	Ctrl+Alt+1	Dots stay fixed with a gentle breathing animation – simple peripheral anchors
Keyboard	Ctrl+Alt+2	Arrow keys manually control dot movement – useful for testing or fine-tuning
Sensor	Ctrl+Alt+4	Real motion from a USB IMU drives the dots — optional, requires a ~$27 IMU sensor — see Sensor Mode below

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Keyboard Shortcuts

Shortcut	Action
Ctrl+Alt+1 / Ctrl+Alt+2 / Ctrl+Alt+3 / Ctrl+Alt+4	Switch mode (static / keyboard / drift / sensor)
Ctrl+Alt+4 (in sensor mode)	Recalibrate gravity reference
Ctrl+~	Toggle dot color (light / dark)
Ctrl+H	Hide / show dots
Ctrl+Up/Down	Increase / decrease dot size
Ctrl+Left/Right	Increase / decrease motion sensitivity
Arrow keys	Simulate motion (keyboard mode only)
Ctrl+Esc	Quit

You can also right-click the system tray icon for Instructions or Quit.

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Running from Source

If you prefer to run from source or want to modify the code:

# Install dependencies
pip install pygame-ce pywin32

# Optional: only needed for Sensor mode (Ctrl+Alt+4)
pip install pyserial

# Run
python motionease.py

Requires Python 3.10+.

To run the unit tests for the sensor parser (no hardware required):

python -m unittest test_sensor_reader.py -v

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Building the .exe

pip install pyinstaller pyserial
pyinstaller --onefile --noconsole --name MotionEase ^
  --hidden-import=serial --hidden-import=serial.tools.list_ports ^
  motionease.py

Output: dist/MotionEase.exe

(--hidden-import flags are needed because pyserial is loaded lazily inside
sensor_reader.start(). Omit them only if you want a build that intentionally
disables sensor mode.)

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The Science

MotionEase is grounded in motion sickness research:

• Sensory Conflict Theory – motion sickness arises from mismatch between visual and vestibular inputs. Peripheral visual anchors reduce this conflict.
• Rest Frame Hypothesis (Prothero, 1999) – the brain needs to identify what is truly stationary. Providing clear rest-frame cues resolves ambiguity.
• 0.2 Hz peak frequency (Diels & Howarth, 2013) – motion sickness peaks at one cycle per 5 seconds. MotionEase’s drift mode targets this band.
• Acceleration-based cues outperform velocity-based cues with less distraction (Applied Ergonomics, 2026).
• Peripheral vision drives spatial orientation – the University of Michigan’s patented approach also targets peripheral light stimuli (US Patent US9862312B2).

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Sensor Mode

Sensor mode (Ctrl+Alt+4) drives the dots from real vehicle motion using a USB IMU — the same kind of acceleration/turn-rate data Apple’s iOS implementation uses.

Hardware

Optional — MotionEase works great without any hardware (drift mode). Sensor mode adds real-time vehicle tracking for a more precise experience.

Currently supported: UeeKKoo RP2350 Development Board (~$27 on Amazon) — a compact IMU (Inertial Measurement Unit) combining an accelerometer and gyroscope on a single board. The factory firmware streams 6-axis IMU data over USB CDC at ~5 Hz; no flashing required. Just plug it in with a USB-C data cable (charge-only cables won’t work).

How it works

1. Press Ctrl+Alt+4. MotionEase auto-detects the device by USB VID/PID (2E8A:0009), opens the COM port, and asserts DTR — the firmware only streams once a real terminal is listening.
2. First launch: hold the device still for ~1 second in its mounted position while gravity and gyro bias are calibrated (5 samples averaged). The result is saved to motionease_sensor_calibration.json next to the exe.
3. Subsequent launches: the saved calibration loads instantly — no wait. The device IS the rest reference until you say otherwise.
4. Live motion mirrors Apple’s iOS Vehicle Motion Cues: dots flow opposite the felt acceleration (so the world appears to pass by like scenery out the window), and the gyroscope’s yaw rate is the primary turn signal — it leads centripetal G during turn entry by ~200 ms, giving snappy response to wheel input.
5. To recalibrate after re-mounting the device, press Ctrl+Alt+4 again. Fresh calibration overwrites the saved file.

Sensitivity

Sensor mode shares the global sensitivity slider — Ctrl+Left / Ctrl+Right adjusts in 0.2 steps from 0.2 to 3.0 (default 1.0). At the default, ~0.2 g of sustained acceleration saturates the dot displacement; gentle road motion produces visible response, hard turns/brakes hit the cue clamp. The current sensitivity is logged to console on every entry into sensor mode.

Fallbacks

• Hardware not connected / cable is charge-only / pyserial not installed: pressing Ctrl+Alt+4 shows a tray balloon with the cause and stays in your previous mode. Modes 1/2/3 keep working exactly as before — sensor support is purely additive.
• Device unplugged mid-session: auto-falls back to drift mode with a tray balloon.
• Saved calibration looks corrupt (gravity magnitude outside 500–1500 mg): MotionEase ignores the file and falls back to fresh runtime calibration; the offending file is logged to motionease_error.log.

Adding other devices

sensor_reader.py is self-contained. To support a different IMU board, change DEVICE_VID/DEVICE_PID and adjust the regexes in _RE_ACC / _RE_GYRO to match its serial output format. The unit tests in test_sensor_reader.py cover the parser and orientation math without hardware.

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License

MIT License. See LICENSE.

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Built with care by the KeepSimple.io team.