Merge branch 'master' into book-announcement

Author: dannystaple

Diff for: content/2025/02/12-rcwl-1601-dimensions/rcwl-1601-distance-sensor-dimensions.png

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+---
+title: Metric Dimensions for the RCWL-1601 Ultrasonic Sensor
+date: 2025-02-12
+tags: [3d cad, robotics cad, robot building, robotics at home, robot sensors, ultrasonic distance sensors]
+description: Metric dimensions for the RCWL-1601 ultrasonic sensor
+thumbnail: content/2025/02/12-rcwl-1601-dimensions/rcwl-1601-distance-sensor-dimensions.png
+---
+These are surprisingly hard to find. So I've made measurements using my digital calipers.
+
+The RCWL-1601 is an ultrasonic distance sensor, which can use the same protocol as the HC-SR04 (but also has i2c and UART modes). It's dimensions do not match the HC-SR04, especially the big cans up front.
+
+So I've modelled in FreeCAD. Here are the dimensions:
+
+![Dimensioned drawing of the RCWL-1601 sensor](/2025/02/12-rcwl-1601-dimensions/rcwl-1601-distance-sensor-dimensions.png)
+
+There are a few caveats to note here:
+
+- I've not drawn the tiny corner holes, they are too small to sensibly use for mounting.
+- My dimensions may not be perfect. I've probably made errors.
+- I've made the board thickness account for the components on the board, so it's a little thicker than the actual board.
+- I've similarly gone for a block for the connectors at the back, which includes space for a connector to be inserted.
+
+Their cans are around 12mm deep, their centres are 22mm apart, and they have a diameter of 16mm.
+
+I hope this is useful to other robot builders out there!