I'm looking to make a random message generator with an accelerometer, something that detects movements and makes snarky comments. I have an Arduino uno, I'm thinking of hooking up an accelerometer and LCD display to output the message once movement has been detected. I've never used an accelerometer before, I only want the movement detection to work at lower frequencies, like 20-100 hertz, I don't want to pick up if someone's cell phone vibrates on the same desk.
Do you have any thoughts on how to create a low pass filter?
Digkey stocks a wide variety of accelerometers. Some have selectable bandwidth. Some have digital outputs and you can implement low pass filtering in your code. If you use an accelerometer having an analog output this can be filtered passively or activity. A one-pole filter can be built using a resistor and a capacitor. Higher order filters can be built with an Op Amp or two.