Working principle of Shape Memory Polymers:
(extract from EPFL’s LMTS webpage on haptic displays and from the project final report)
Here you find a Movie showing the flexible version of our 24×32 element active skin: i) displaying different patterns, ii) device operating principle, and iii) dynamic thermal imaging showing selective taxel heating. Published in Advanced Materials Technologies 2017.
Operating principle for a single SMPs taxel. Synchronizing the global pneumatic actuation and the Joule heating switches the taxel from up to down, or vice versa.
Photo and exploded view of the 4×4 SMP haptic display
24×32 haptic display with 768 independent SMP actuators, showing the BlindPad logo. The SMP actuators were made at EPFL, the control electronics and firmware by BlindPad partner IIT, and control software by BlindPad partner Geomobile.
Pictures of each separated parts used to drive in the 32×24 SMP prototype. The hardware (actuators + pumps), the driver board and the software are shown.
Picture of the 32×24 SMP prototype with the pin interface (from IIT) and the copper plate to speed up the refresh time.