Achieving 0.02mm absolute positioning accuracy through comprehensive kinematic parameter identification and compensation
A major automotive manufacturer required extreme precision for their robotic welding and assembly operations. Their standard industrial robots, while repeatable, suffered from absolute positioning errors up to 2mm due to manufacturing tolerances and kinematic parameter deviations.
CalibWorks developed a comprehensive parametric calibration system that identifies and compensates for all kinematic errors, achieving absolute positioning accuracy of 0.02mm - a 100x improvement that enabled previously impossible assembly tasks.
Complete kinematic model identification
Overcoming industrial robot limitations
Robot components have inherent manufacturing variations that accumulate to create significant end-effector positioning errors.
Temperature variations cause link expansion and joint encoder drift, requiring dynamic compensation models.
Joint compliance and structural deflection vary with payload weight and center of gravity location.
Gear backlash, encoder eccentricity, and cable tension create complex non-linear positioning errors.
Calibration measurement system must be 10x more accurate than target robot precision.
Parameter errors are coupled, requiring sophisticated optimization to separate individual contributions.
Systematic approach to robot accuracy
500+ poses measured with laser tracker
Non-linear optimization of kinematic parameters
Independent test poses verify accuracy
Upload compensation to robot controller
Continuous accuracy tracking
Before and after calibration metrics
| Metric | Before Calibration | After Calibration | Improvement |
|---|---|---|---|
| Absolute Position Error | 2.0mm | 0.02mm | 100x |
| Orientation Error | 0.5° | 0.01° | 50x |
| Path Following Error | 1.5mm | 0.05mm | 30x |
| TCP Drift (8 hours) | 0.8mm | 0.03mm | 27x |
| Load Sensitivity | 0.5mm/kg | 0.01mm/kg | 50x |
Transforming manufacturing precision
Precision enabling new possibilities
CalibWorks' parametric calibration transformed our production line. We went from scrapping parts due to misalignment to achieving aerospace-level precision with standard industrial robots. The 0.02mm accuracy enabled us to automate assembly processes we thought would always require human workers. With 320 robots now calibrated, we've saved millions in both capital equipment and operational costs.
Transform standard industrial robots into precision instruments with parametric calibration.