The physical unclonable function (PUF) is a method to derive ID information peculiar to a device by detecting random physical features that cannot be controlled during the device’s manufacture. Because information such as the ID information is difficult to replicate, PUF is used as a technique to prevent forgery. PUF has two major application fields: an authentication scheme, and protection of intellectual property of the semiconductor industry. Several circuit systems to compose PUF have been reported. This study proposes a new PUF based on ring oscillator PUF. By incorporating a mechanism to correct the oscillation frequency dispersion that results from the layout, the proposed PUF can generate ID accurately. We verified the proposed PUF’s validity by conducting experiments using an FPGA that incorporates the proposed PUF.
In this paper, we consider visual feedback stabilization which tolerates small camera misalignment. Specifically, a balancing task with a cart-pendulum system using camera image is examined. Such a task is known to rely heavily on the detection of the vertical direction and the angle measurement error due to the camera misalignment could be fatal for stabilization. From a mathematical model of the measurement error, the effect of the misalignment is naturally represented by affine perturbation to the coefficient matrix of the output equation. Motivated by this fact, a special type of robust dynamic output feedback stabilization against polytopic uncertainty is investigated. By solving the related BMI, one can design a controller which tolerates the camera misalignment to some extent. The result is verified via experiments.