Surrounding Object Material Detection and Identification Method for Robots Based on Ultrasonic Echo Signals

Table 2

Optimal hyperparameter for SVM, KNN, and decision tree.

Algorithms	Hyperparameters	Values
SVM	Kernel	Gaussian
	C	0.1
	Sigma	4.1
KNN	K neighbors	15
	Distance metric	Euclidean distance
Decision tree	Max. number of divisions	10
	Classification criteria	Gini coefficient