I am using the CapSense library to detect in a hand is in contact with a metal coated plastic handle. Although things work generally, the detection is not robust. Sometimes I can touch the handle and is is detected every time. Other times, it fails to detect anything. I only need to detect absolute touch. I do not want to detect something close to the handle.
I have the lead to the handle configured as documented in the CapSense web page. The back side of the handle is grounded and attached to ground on the Arduino. This is not a true ground.
I am using a 1MOhm resister and at this point I don't have a capacitor to filter the input.
Right now I am using a breadboard to prototype. It seems that just lifting the bread board off the table is sufficient to get it to make the detection work.
How can I improve the detection?