Figure 6. Overall in vitro target tracking performances between target profiles and measured Erk phosphorylation.

Experiments with target trajectories (solid black) defined by the (t_off, p_ss) pairs of (A) (8,0), (B) (15,0) and (C) (22,0). Data are measurements of plant dynamics that were uncontrolled (UC, cyan triangle, n = 12) and controlled by S_Z (blue square, n = 9), S_L (green x, n = 9), S_K (red circle, n = 9) and M_aw (magenta dot, n = 9). Data shown are mean ± standard error. (D) Controller performances as measured by squared error between target trajectories and controlled plant dynamics. Group letters denote statistically significant differences between groups (p<0.05) as calculated by one-way ANOVA with Tukey multiple comparisons test (SigmaStat v3.5, Systat Software, Inc).