There are a surprising wealth of parts inside of old laptops that can be easily scavenged, but often these proprietary tidbits of electronics will need a substantial amount of work to make them useful again. Obviously things such as hard drives and memory can easily be used again, but it’s also possible to get things like screens or batteries to work with other devices with some effort. Now, there’s also a way to reuse the trackpad as well.

This build uses a PS/2 touchpad with a Synaptics chip in it, which integrates pretty smoothly with an Arduino after a few pins on the touchpad are soldered to. Most of the work is done on the touchpad’s built in chip, so once the Arduino receives the input from the touchpad it’s free to do virtually anything with it. In this case, [Kushagra] used it to operate a stepper motor in a few different implementations.

If you have this type of touchpad lying around, all of the code and schematics to make it useful again are available on the project page. An old laptop in the parts bin is sure to have a lot of uses even after you take the screen off, but don’t forget that your old beige PS/2 mouse from 1995 is sure to have some uses like this as well.

Phone screens keep getting bigger. Computer screens keep getting bigger. Why not a large trackpad to use as a mouse? [MaddyMaxey] had that thought and with a few components and some sewing skills created a trackpad in a tablecloth.

The electronics in this project are right off the shelf. A Flora board for the brains and 4 capacitive touch boards. If you haven’t seen the Flora, it is a circular-shaped Arduino made for sewing into things. The real interesting part is the construction. If you haven’t worked with conductive fabric and thread, this will be a real eye-opener. [Maddy’s] blog has a lot of information about her explorations into merging fabric and electronics and also covers things like selecting conductive thread.

As an optional feature, [MaddyMaxey] added vibration motors that provide haptic feedback to her touchpad. We were hoping for a video, but there doesn’t seem to be one. The code is just the example program for the capacitive sensor boards, although you can see in a screenshot the additions for the haptic motors.

We’ve covered the Flora before, by the way. You could also make a ridiculously large touch surface using tomography, although the resolution isn’t quite good enough for mouse purposes.