Check hand actions
When the point is "what the hand did" and the frame shows no result afterwards, or the result only flashes by, use the hand action group - near, grip, in zone, left zone, pick up, put back and in hand. Action count, which counts how many times a screw was really driven, is in the [Counting](./count#action-count) group.
Use this group when the point is "what the hand did", and the frame shows no result afterwards or the result only flashes by.
- The workstation has a built-in hand recognition model, so you do not add "hand" to the class table.
- Distances are measured in multiples of the palm size, not pixels, so how far the person is from the camera does not matter.
Do not use hand types for steps whose result stays visible in the frame
For steps such as "it is inside" or "it is connected", use object types. Hand rules only look at the action: if a worker just waves a hand over it and the part is not installed correctly at all, it still passes.
Hand near object
What it judges: a fingertip or the palm comes within a certain distance of a part and stays there.
Typical uses: touching a button; reaching for a part.
How to configure:
- Part classes: you can select several; any instance matching is enough;
- Which hand: left / right / either;
- Contact distance: × palm, default 0.8.
Grip object
What it judges: the hand touches the part and the fingers bend to grip it; an open hand resting against it does not count.
Typical uses: gripping a tool; grabbing a sponge; grabbing parts in a material box.
How to configure:
- Part class;
- Which hand;
- ROI zone (optional): only grips inside this zone count;
- Grip strength: default 0.45; lower to 0.3 for pinching small parts.
Hand in zone
What it judges: the palm is in the detection zone right now, for the full "hold time".
Typical uses: reaching into a material box to pick; the hand entering the station.
How to configure: ROI zone; which hand.
When the material box can be fixed in place, the parts in it need no labeling
Just use "Hand in zone" to judge "material picked"; see Avoid common pitfalls.
Hand left zone
What it judges: a hand was first seen in the zone, and then all hands left it.
Typical uses: finishing an operation, with the hands leaving the work area; making sure the hand is away before a length ratio check.
How to configure: ROI zone.
Pick up object
What it judges: after the hand touches the part, the part moves with the hand; that counts as picked up.
Typical uses: picking up a circuit board from a material box; taking out a part.
How to configure: part class; which hand; ROI zone (optional; the part must be picked from this zone).
Put back object
What it judges: the hand holds the part, then puts it down and lets go; that counts as put back.
Typical uses: putting a part back into the material box; putting a finished product into a tote.
How to configure: part class; which hand; ROI zone (optional; the part must land in this zone).
Object in hand
What it judges: the hand is really holding this part (the hand box and the part box overlap).
Typical uses: confirming the right part is being held while the action is in progress.
Object in hand is not a catch-all fallback
For a part placed on the station, use "Object present + select a zone"; for a part going into a container, use "Inside container".