A piecewise linear method for analyzing 
supercavitation navigation body kinetic characteristics includes the steps that step1, a 
supercavitation navigation body 
kinetic model is built; step2, piecewise 
linear fitting is performed on a non-linear sliding 
force function in the 
supercavitation navigation body 
kinetic model to obtain a linear sliding 
force function; step3, parameters of the supercavitation 
kinetic model are set; step4, the supercavitation kinetic model with the piecewise linear sliding force Fp function is adopted for obtaining a sole 
balance point of a supercavitation navigation body, 
linearization is performed on a 
system at the 
balance point to obtain a jacobian matrix of the 
system and a 
characteristic equation at the 
balance point, characteristic values of the 
system are obtained, and the balance point of the system is judged to be an unstable 
saddle focus. By the adoption of the 
piecewise linearization of the sliding 
force function, the supercavitation navigation body kinetic model is simplified, so that the balance point position and 
stability conditions of the model have concise 
analytical expressions, and the supercavitation navigation body kinetic characteristics are analyzed more conveniently.