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Accelerometer

Live accelerometer readings for device acceleration and tilt, with combined and per-axis graphs.

iPhoneiPadMacApple Vision ProApple TVApple Watch
Overview tab with live acceleration values

Overview​

The accelerometer measures acceleration along the device axes. This includes gravity, so the readings can be used to estimate tilt.

Table of Contents​

Tabs​

  • Overview
  • Graphs (combined)
  • Graphs (per axis)

Toolbar Controls​

All motion-sensor tools share the same toolbar controls:

  • Play / Pause: start or pause sensor updates.
  • Clear: clear history buffers used by the graphs.
  • Refresh rate: cycle between Faster, Fast, and Slow sampling rates.

Overview Tab​

The Overview tab features a real-time 3D Metal-rendered wireframe sphere that tilts based on accelerometer data. The sphere is composed of meridians and parallels, with color-coded axis arrows extending from the origin (X = red, Y = green, Z = blue) with arrowhead indicators. A low-pass filter smooths the sphere's pitch and roll derived from the X and Y acceleration values, preventing jitter from raw sensor noise.

Below the visualization, the tab shows current axis values:

  • accX (X axis)
  • accY (Y axis)
  • accZ (Z axis)

Values are shown in g.

Graphs Combined Tab​

Graphs (combined): X/Y/Z plotted together

This tab overlays X/Y/Z history on a single graph (X = red, Y = green, Z = blue). The Y-axis range is fixed at -3 to +3 g. Current values are displayed with split-precision formatting (the first 4 decimal places are bold, remaining decimals are semi-transparent). The graph retains the last 100 readings.

Graphs Per Axis Tab​

Graphs (per axis): one panel per axis

This tab shows three separate panels (X, Y, Z), each with a dedicated graph and the current value displayed alongside the axis label.

What You Can See​

  • Acceleration along the X/Y/Z axes
  • Units (commonly g or m/s^2)
  • Optional graph/history view (if available)

Notes​

  • When the device is still, most of the signal is gravity.
  • Sudden movement or vibration will show as spikes.

Notes And Limitations​

  • On Mac Catalyst, motion sensors may be unavailable.
Last updated on by Roger Hirooka