we have designed two kinds of probes, one can probe vertically (the one we used here). Another one can probe from a tilted angle, which can probe a pad from the side. We decided to use the vertical probe since it's currently easier to realize. The probing position is not the center of the pads, but add a tiny bias from the center, so the probe won't be blocked by the components. We will improve the design allowing probe tilting for use in cases where a pad can’t easily be accessed only by vertical movement and/or component shape inhibits easy access to a pad.