Fillets and bitbanging

November 27, 2018

This week there’s been some more work on the IOTCompass project. I realised that the GPS and Compass module actually had two connectors. A serial one for the GPS functionality and a separate I2C based compass module.

The SDK for the Azure Sphere does not support I2C yet so I’ve been attempting to get that to work using software I2C aka bitbanging.

Models

I’ve also been working on the 3D CAD models for the project. I’ve created a “sweeper” to cover the reflective IR sensor once per revolution. There’s nothing particularly sophisticated about this design. I created it with similar techniques to the base plate using construction lines to find the middle and 2 more 1.6mm from the centre. A 5.2mm circle was sketch on the centre line. Straight lines were added along those 1.6mm construction lines and then the edge of the circle trimmed away. A 5.2mm counter bore was then added so the sweeper will sit down near the face of the motor.

The second part created was the pointer. This had a similar construct so that it would fit onto the motor spindle. The key feature of this design was some splines for the curved point and tail, and many fillets.

Some 2D filtets were added to the sketch so that the tips of the point and tail were not so sharp. This should help it print better. Also fillets were added around the boss the middle to ensure the junction is nice and strong.

By Andy from Workshopshed One Comment

  Posted in: IOTCompass Tags: AzureSphere, CAD, I2C