Figure 7.

Selection of optimal exploratory movements for pilot study of 10 textures. Tables present the uncertainty calculated for each measurement property for combinations of contact force and sliding velocity. Gray boxes with white numbers in the lower-right half plane represent exploratory movements that were excluded due to the high wear rate high force and velocity combinations had on the skin. Values in the upper left half plane are coded from blue to white to represent decreasing uncertainty with lower values being ideal for discrimination of the 10 textures. From this the three of the most useful movements were selected as 1.26 N and 1 cm/s for discrimination based on traction, 0.2 N and 6.31 cm/s for discrimination based on roughness, and 0.5 N and 2.5 cm/s for discrimination based on fineness. Movements at 0.2 N and 2.5 cm/s were not selected for the roughness or fineness measures because they appeared to be outliers and did not fit the general trend of performance from neighboring movements.