Abstract:
Sensitive skin is a large-area, flexible array of sensors with data processing capabilities, which can be used to cover the entire surface of a machine or even a part of a human body. Depending on the skin electronics, it endows its carrier with an ability to sense its surroundings via the skin’s proximity, touch, pressure, temperature, chemical/biological, or other sensors. Sensitive skin devices will make possible the use of unsupervised machines operating in unstructured, unpredictable surroundings among people, among many obstacles, outdoors on a crowded street, undersea, or on faraway planets. Sensitive skin will make machines “cautious” and thus friendly to their environment. This will allow us to build machine helpers for the disabled and elderly, bring sensing to human prosthetics, and widen the scale of machines’ use in service industry. With their ability to produce and process massive data flow, sensitive skin devices will make yet another advance in the information revolution. This papersurveys the state of the art and research issues that need to be resolved in order to make sensitive skin a reality.
1. INTRODUCTION
Sensitive skin represents a new paradigm in sensing and control. These devices will open doors to a whole class of novel enabling technologies, with a potentially very wide impact. Far-reaching applications not feasible today will be realized, ranging from medicine and biology to the machine industry and defense. They will allow us to fulfill our dream for machines sensitive to their surroundings and operating in unstructured environment.
Some applications that sensitive skin devices will make possible are yet hard to foresee. Flexible semiconductor films and flexible metal interconnects that will result from this work will allow us to develop new inexpensive consumer electronics products, new types of displays, printers, new ways to store and share information (like electronic paper and “upgradeable” books and maps). New device concepts suitable for large area flexible semiconductor films will lead to new sensors that will find applications in space exploration and defense, specifically in mine detection and active camouflage.
2. SYSTEM CONCEPT
Sketch of interconnects between sensors, intelligence, and actuators
The system consists of a number of distributed sensor, actuator, and intelligence units, which are connected by some network of interconnects. The interconnects are necessary for providing power to the system as well as for communication. The sensors/actuators themselves may have intelligence associated with them, but there are other higher levels of intelligence to which they are connected. The interconnects shown in the system might be electrical (conventional wires) or optical (fibers). The communication via the individual units might in some cases be “wireless” (implying also fiber-less) for some structures. For delivering power, it was thought that the system probably would require physical interconnects (i.e. power delivered through fibers or wires), and that “harnessing” energy from the environment, such as via solar or RF pick-ups, would not be practical for most applications (especially for wireless systems). Therefore in all cases there would have to be a physical interconnect between the individual sensor / actuator / intelligence blocks, and so a major part of this report addresses issues associated with this physical level of interconnection.
Potential applications of sensitive skin
Four groups of research issues must be addressed in order to develop sensitive skin: Skin Materials, Sensing Devices, Signal and Data Processing, and Applications.
