DIY SpaceMouse Makes Fusion 360 Navigation Easy

Comuter-aided design is difficult for many reasons, but the biggest challenge for most people is learning to translate the image of a 3D object in their heads into a series of 2D profiles and operations. That is further exacerbated by the fact that our tools (our computer monitors and mice) work on 2D planes, so even navigating within the virtual 3D environment of a CAD software can be tricky. Special input devices can make that much easier and the 3Dconnexion SpaceMouse is one of the most popular. But that's pricey, so Salim Benbouziyane designed his own DIY alternative.

The goal of the 3Dconnexion SpaceMouse and this DIY version is to make 3D navigation more intuitive. The user can manipulate the SpaceMouse almost like they're interacting with the virtual 3D model, so manipulating the SpaceMouse causes the view port to either orbit or pan around the object. That is much easier to wrap one's head around than trying to remember which buttons to press while moving a conventional mouse on a 2D plane (the desk or mouse pad). This DIY SpaceMouse also has two shortcut buttons: one to move the model into the home view orientation and one to fit the model to the screen.

There are many, many ways that a person could design a device to achieve this effect. Benbouziyane chose an elegant solution that keeps the hardware complexity to a minimum. The key component is an Adafruit TLV493D triple-axis magnetometer. That mounts onto a small platform and several permanent magnets mount onto a base. A system of six springs (three compression springs and three extension springs) suspends the platform above the base, but still lets the user manipulate the platform's position relative to the base. As they do, the magnetometer registers changes in the magnetic fields in the three axes so it can monitor its own orientation.

An Adafruit QT Py RP2040 development board monitors the values of those axes. Benbouziyane configured it to appear as a standard USB HID keyboard and mouse when connected to a computer. In response to manipulation of the platform (onto which a handle attaches), it sends the appropriate key presses and mouse cursor movements needed to reorient the view port to match.

All of the mechanical components, aside from the springs and fasteners, are 3D-printable. Benbouziyane uploaded the STL files, code, and instructions here to Hackster, so you can build this SpaceMouse yourself to improve your CAD experience. This is set up specifically for Fusion 360, but the code can be tweaked to work with other software.