Structural identifiability of controlled state space systems: a quasiautomated methodology for generating identifiable reparameterisations of unidentifiable systems

In this paper two of the most commonly used approaches to the structural identifiability analysis of controlled nonlinear parameterised systems are described. The application of these techniques within symbolic manipulation packages is also illustrated. Whilst this analysis has been performed using Mathematica it could equally well have been carried out within most other currently available symbolic software packages. A problem that arises in structural identifiability analysis is what to do with unidentifiable systems. A procedure for generating locally identifiable reparameterisations of unidentifiable nonlinear systems is also presented in this paper. This procedure can be almost completely performed within an appropriate symbolic manipulation package as illustrated by the example presented