Towards standardization of EAP actuators test procedures: Fid-Bau Portal

Towards standardization of EAP actuators test procedures

Fernandez, D. / Moreno, L. / Baselga, J.

Since the field of electroactive polymers (EAP) actuators is fairly new there are no standard testing processes for such intelligent materials. This drawback can seriously limit the scope of application of EAP actuators, since the targeted industrial sectors (aerospace, biomedical...) demand high reliability and product assurance. As a first iteration two elements are required to define a t est standard for an EAP actuator: a unit tester, and a component specification. In this paper a EAP unit tester architecture is presented along with the required classification of measurements to be included in the EAP actuator component specification. The proposed EAP Unit Tester allows on-line monitoring and recording of the following properties of the specimen under test: large deformation, small tip displacement, temperature at the electrodes, weight of the specimen, voltage and current driven into the EAP, load being applied to the actuator, output voltage of the EAP in sensing operation and mode of operation (structure/sensor/actuator/smart). The measurements are taken simultaneously, in real-time. The EAP unit tester includes a friendly graphical user interface. It uses embedded Excel tools to visualize data. In addition, real-time connectivity with MATLAB allows an easy testing of control algorithms. A novel methodology to measure the properties of EAP specimens versus a variable load is also presented. To this purpose a force signals generator in the range of mN was developed. The device is based on a DC mini-motor. It generates an opposing force to the movement of the EAP actuator. Since the device constantly opposes the EAP actuator movement it has been named digital force generator (DFG). The DFG design allows simultaneous length and velocity measuring versus different load signals. By including such a device in the EAP unit tester the most suitable application for the specimen under test can be easily identified (vibration damper, large deformation actuator, large force actuator, fast actuator...).