Table 4 Reproducibility of estimated parameters (desired image of string: J)
From: Dynamic manipulation of unknown string by robot arm: realizing momentary string shapes
Each parameter | Trial no.0 | Trial no.1 | Trial no.2 | Trial no.3 | Trial no.4 |
|---|---|---|---|---|---|
Spring constant \(k_{s}\) (N/m/kg) | \(9.0 \times 10^{5}\) | \(4.9 \times 10^{5}\) | \(4.2\times 10^{5}\) | \(5.2\times 10^{4}\) | \(2.5\times 10^{5}\) |
Damping coefficient \(c_{s}\) (Ns/m/kg) | 57 | 19.1 | 3.3 | 4.3 | 4.1 |
Hinge spring constant \(k_{h}\) (Nm/rad/kg) | 0.57 | 7.0 | 2.7 | \(8.0\times 10^{-3}\) | \(1.3\times 10^{-2}\) |
Hinge damping coefficient \(c_{h}\) (Nms/rad/kg) | \(2.5 \times 10^{-2}\) | \(2.8 \times 10^{-2}\) | \(5.5\times 10^{-2}\) | \(8.5\times 10^{-4}\) | \(9.8\times 10^{-7}\) |
Air resistance proportional coefficient \(C_{c1}\) (Nms/rad/kg) | 0.52 | \(1.2 \times 10^{-4}\) | \(1.0 \times 10^{-4}\) | \(1.8 \times 10^{-4}\) | \(1.8 \times 10^{-4}\) |
Air resistance squared proportional coefficient \(C_{c2}\) (Nms/rad/kg) | 0.26 | 0.51 | \(6.9\times 10^{-4}\) | 1.1 | \(1.7\times 10^{-4}\) |
Hinge spring constant of grasp point \(k_{ph}\) (Nm/rad/kg) | 0.27 | \(6.4 \times 10^{-3}\) | \(8.1 \times 10^{-3}\) | 5.0 | \(7.5 \times 10^{-3}\) |
Hinge damping coefficient of grasp point \(c_{ph}\) (Nms/rad/kg) | \(7.3\times 10^{-3}\) | \(9.6\times 10^{-5}\) | \(1.4\times 10^{-2}\) | \(7.7\times 10^{-5}\) | \(4.6\times 10^{-3}\) |