The piezoelectric actuator (PEA) is a device which performs very small displacements
within the range of less than or equal to 100 μm. However, the PEAs suffer from the
inherent non-linearity because of the hysteresis, creep and vibrations effects. These
effects may cause a displacement error as high as 15% of the total range. This high error
shows the necessity of a controller. Due to Sliding Mode Control (SMC) simple design
steps, high robustness and low sensitivity to disturbances, it has been implemented to
overcome and minimize the error. This research project has successfully accomplished
the following three objectives. The first is to overcome the robustness and accuracy issue
by applying the SMC method which is robust and accurate, using the mathematical model
of the PEA which includes all the uncertainties and disturbances. The second is to apply
the Terminal Sliding Mode Control (TSMC) concept to overcome the global infinite time
stability to reach convergence or zero error in finite time. The third is to reach chattering
free non-singular system. Chattering and singularity phenomena reduce the service
lifetime of the PEA and create unwanted noise in the control input single. To reduce the
chattering, sigmoid (sig) function has been used in the sliding function. This method is
called continues terminal sliding mode. To overcome the singularity problem, the sliding
function and the derivative of the sliding function does not result in terms with negative
(fractional) powers which mean there will be no singularity. The chattering free nonsingular
finite time system has been proved mathematically and in the simulation
