**Author details**

634 Smart Actuation and Sensing Systems – Recent Advances and Future Challenges

mainly depend on the design of the architecture of the ASIC.

integration. The main achievements are summarized below.

PVDF creep and recovery following a step in load or temperature.

been used as reference specifications to design the interface electronics.

**7. Conclusions** 

the interface electronics.

contact).

To be able to integrate the interface and the data acquisition/local processing electronics onto the bottom of each triangle, and due to the small space available, an applicationspecific integrated circuit (ASIC), see Figure 15, which embeds: a) the interface electronics; b) data acquisition; c) dedicated signal processing; d) communication bus interface should be pursued. The feasibility and integration of the tactile sensing system on the robot will

The main objective of the research activity in this area is the design and manufacturing of robotic skin systems based on arrays of PVDF film transducers. We addressed issues concerning the manufacturing technology, the interface electronics and the system

The electromechanical characterization of PVDF thin films working in thickness mode has been achieved. The experimental *d33* characterization shows a flat behavior in the whole range of frequencies of interest for the present application. Future steps would include the characterization of the PVDF tangential piezoelectric moduli and of the polymer behavior when used in bending mode. Another field of interest is related to the interpretation of

A number of elementary qualitative tactile perceptions have been experimentally quantified i.e. the corresponding mechanical contact force/stress have been evaluated. The contact pressure spans on about 5 orders of magnitude ranging from 50Pa to 5MPa. Achieved results complete relevant information in the latest literature about skin and perceived contacts. The contact stress/force range has been used as reference for the development of

The PVDF transducer charge response to contact stresses has been evaluated in the defined range. We measured the charge response of a set of single taxel prototypes (i.e. PVDF thin film + cover layer) and we focused on gel/rubber layers excluding foams, to get more controllable and reproducible systems which also allow for the required dynamics. Measured charge spans over a range from about 0.01pC up to 1-2nC. The charge response results have been compared with an electromechanical model of the skin structure and have

The interface electronics has been designed, implemented and tested. Experimental results validate the proposed solution in the frequency band of interest. The output signal ranges over three orders of magnitude. The experimental tests highlighted the need of a variable gain electronics solution to be able to measure the wide range of tactile stimuli expected for the application (i.e. 5 orders of magnitude for the expected mechanical stress due to

The manufacturing technology for PVDF sensors arrays has been identified. In particular, the thickness (i.e. approximately 3mm) and material (PDMS) of the protective layer for the Lucia Seminara and Luigi Pinna *Department of Biophysical and Electronic Engineering - University of Genoa, Italy* 

Maurizio Valle *Department of Biophysical and Electronic Engineering - University of Genoa, Italy Research Center on Materials Science and Technology - University of Genoa, Italy* 

Marco Capurro *Research Center on Materials Science and Technology - University of Genoa Department of Civil, Environmental and Architectural Engineering - University of Genoa, Italy* 
