Figure 8

Kernel density estimations of the position precision of the tool center point (TCP) between the new approach using key performance indicator and (a) the heuristic approach and (b) the state-of-the-art optimization approach. The Histogram presents the difference of TCP precision of working configuration \(\boldsymbol {q}^{\mathrm{work}}\) from the new approach using KPI and the heuristic/state-of-the-art optimized measurement configurations \(\boldsymbol {q}_{x}^{\mathrm{meas}}\), where \(x \in\{{h}, \boldsymbol {p}\}\) for 90 parameter identifications differing in the industrial manipulators’ models. Higher values on the x-axis mean a better result of the new approach. The optimized measurement configurations \(\boldsymbol {q}_{p}\) and \(\boldsymbol {q}_{s}\) result by solving the optimization problems: \(\boldsymbol {q}_{p}^{\mathrm{meas}} :=\min_{ \boldsymbol {q}^{\mathrm{meas}}} \operatorname {tr}( {C}_{p}( \boldsymbol {q}^{\mathrm{total}}))\) and \(\boldsymbol {q}_{s}^{\mathrm{meas}} :=\min_{ \boldsymbol {q}^{\mathrm{meas}}} \operatorname {tr}( {C}_{s}( \boldsymbol {q}^{\mathrm{total}}))\).