A few of us have been talking about experimenting with different sensors on the pivot arms. I've been considering several different types of hall sensors from simple 3 wire ratiometric sensors to more complicated rotary/angle encoders. SC-Maik is working on a design using a similar 3 wire sensor, and zdayton was discussing using a angular encoder.
I was hoping we could centralize this discussion here rather than in various posts across our different build threads.
For those wanting to try out similar builds, one option would be ordering samples. Some manufacturers offer limited free samples, you just need to register on their site.
I requested samples from AMS. You can request 3 of each of 3 different products per month for free for sample purposes. Here's the listing page. http://ams.com/eng/Products/Position-Se ... on-Sensors
I'll have a couple of TSSOP-14 and SOIC-8 chips to test with. I'll need to go back over the data sheets and see which I'm more interested in working with. This one in particular is interesting - http://ams.com/eng/Products/Position-Se ... ors/AS5600
That chip provides a linear analog output of 0-360 degrees, but that range can be programmed to a user specified range, either a full 360 degrees, 180, 90 or 45 degrees. The 90 degree range would be more than enough movement for a pivot arm. I think that'd provide enough accuracy and be fairly easy to implement. It's also a less expensive component when it comes time to buy.
It's worth noting that they also have magnets and interesting hall effect joystick modules that might make for a good hat switch. If you don't want to experiment with different sensors you could get 3 of the sensor you want to use, 3 magnets, and a couple joystick modules.