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Amorphous carbon (a-C) and amorphous hydrogenated carbon (a-C:H) films are produced by 248 nm pulsed laser ablation of graphite and polycarbonate targets in high vacuum conditions. Plasma plumes generated by target irradiation with different laser fluences are investigated with laser induced fluorescence spectroscopy and an electrostatic probe. Ions of C2+ with kinetic energies of several hundred eV are detected in the leading edge of the plasma plumes from both targets. These energetic species are proposed to be responsible for the formation of film structures corresponding to diamond-like carbon (DLC), as it is found from electron-energy-loss spectroscopy (EELS) and Raman investigations of 0.5 μm films deposited onto steel substrates. The validation of a laser wavelength/fluence region for DLC formation found earlier for graphite targets is discussed and expanded to polycarbonate targets. An increase in laser fluence leads to higher percentages of sp3 bonds in the a-C and a-C:H films. For the a-C:H films, the incorporation of large molecular conglomerates ejected from polycarbonate targets results in the formation of unique heterogeneous structures revealed from scanning electron microscopy (SEM) studies. The embedded conglomerates cause a decrease in the a-C:H film hardness to 15 GPa, in comparison to 60 GPa for the a-C films.

This paper presents Skye, a novel blimp design. Skye is a helium-filled sphere of diameter 2.7m with a strong inelastic outer hull and an impermeable elastic inner hull. Four tetrahedrally-arranged actuation units (AU) are mounted on the hull for locomotion, with each AU having a thruster which can be rotated around a radial axis through the sphere center. This design provides redundant control in the six degrees of freedom of motion, and Skye is able to move omnidirectionally and to rotate around any axis. A multi-camera module is also mounted on the hull for capture of aerial imagery or live video stream according to an 'eyeball' concept -the camera module is not itself actuated, but the whole blimp is rotated in order to obtain a desired camera view.Skye is safe for use near people -the double hull minimizes the likelihood of rupture on an unwanted collision; the propellers are covered by grills to prevent accidental contact; and the blimp is near neutral buoyancy so that it makes only a light impact on contact and can be readily nudged away.The system is portable and deployable by a single operator -the electronics, AUs, and camera unit are mounted externally and are detachable from the hull during transport; operator control is via an intuitive touchpad interface.The motivating application is in entertainment robotics. Skye has a varied motion vocabulary such as swooping and bobbing, plus internal LEDs for visual effect. Computer vision enables interaction with an audience. Experimental results show dexterous maneuvers in indoor and outdoor environments, and non-dangerous impacts between the blimp and humans.

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