1. Observe
Trigger, illumination or projection, capture and transfer of depth data. Vibration or motion may require another capture.
Knowledge · Robotics
What determines 3D bin-picking cycle time?
The relevant measure is not the speed of one scan or robot move, but the production time required for one correctly picked and accepted part. Failed attempts, new captures and recovery therefore belong in the same time budget.
The right metric
Measure time per correct pick
First choose clear start and end points. A cycle might begin when a new capture is released and end when the part is correctly placed at its destination and the next cycle may start.
Measure a representative production window and divide total elapsed time by the number of accepted picks. Include waiting, missed picks, repeated captures and automatic recovery. State explicitly which planned breaks or external line stops were excluded.
Measurement model
Time per correct pick = observed production time / accepted picks
Use the same definition for every product variant and bin condition. Only then can trials and changes be compared.
Time budget
Where the time actually goes
2. Estimate the part pose
Process points, separate parts and determine position and orientation. Product variation and limited visibility affect computation time and confidence.
3. Validate a grasp
Select a reachable grasp and verify that the gripper, part and approach remain clear. The technical detail belongs in grasp planning.
4. Move the robot
Approach, pick, withdraw, transfer and place. Path length, safe speeds and robot configuration often account for a substantial part of the cycle.
5. Confirm the pick
Jaw position, vacuum pressure or an additional check confirms that one part was correctly picked and placed.
6. Recover
A failed attempt may require returning the part, measuring again, trying another grasp or requesting operator assistance. These exceptions determine effective output.
From cycle to capacity
Theoretical speed is not line output
Convert measured time into capacity using the cell's measured availability. Then compare that result with supply, downstream processing, buffers and product changeovers. The slowest connected process constrains the line.
Calculation model
Picker capacity per hour = 3,600 × availability / time per correct pick
Use availability as the measured share of scheduled production time. Report variation and adverse production periods as well as an average.
Business case
Compare achievable output with manual hours per shift, labour cost, intervention time, changeover, maintenance, investment and demonstrably avoided scrap or downtime. A payback model is useful only when these inputs come from the actual production process.
Targeted improvement
Optimise the critical path, not every step in isolation
Run tasks in parallel
The next capture can sometimes occur during placement or withdrawal. First verify motion in the image, safety and the actual critical path.
Reduce the search space
Use the relevant bin volume and prevalidated grasps, provided they still cover product variation and reachability.
Shorten robot travel
Position the bin, camera and destination to avoid long moves and awkward wrist poses without compromising access or safety.
Design recovery first
Define when the cell tries an alternative, captures again, changes the part presentation or requests help. A short nominal cycle cannot compensate for frequent long interruptions.
Representative trial
Build the capacity claim on real production data
Share part variants, bin dimensions, required output, shift pattern and adjacent process steps. A trial can then record time per correct pick, availability, recovery and constraints.