In the industry motion systems with electric motors are used for transporting and positioning thin flexible substrates at high throughput rates. A possible alternative actuation solution could be to apply contactless air film actuators which make use of air bearing principles. Th
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In the industry motion systems with electric motors are used for transporting and positioning thin flexible substrates at high throughput rates. A possible alternative actuation solution could be to apply contactless air film actuators which make use of air bearing principles. The air film actuators use a thin film of air to levitate and propel a substrate. The main advantage of such a technique is that it actuates directly on the substrate and therefore eliminates the moving mass of a carrier. This drastically reduces the actuation force required to accelerate the substrate, which reduces unwanted deformations and excitations of the machine frame. Because the substrate is not in direct contact with the bearing surface, the substrate does not experience any wear, stiction or backlash effects. In this project a demonstrator with opposed air film actuators is designed and manufactured to actuate a flexible substrate in one degree of freedom. To predict the performance of the motion system, the air film actuators are modelled with the use of the Reynolds equation for compressible air, determined both analytically and numerically. The demonstrator consists of two manifolds with their bearing surfaces facing each other and where a substrate is placed between the two bearing surfaces. By using pressurized air, the substrate can be levitated between the two bearing surfaces. By controlling proportional valves, the substrate can be moved in negative or positive x-direction. The theoretical models show good resemblance with the measurement results. However, the substrate vibrated and did not float fully contactless between the two bearing surfaces. Based on these results, improvements can be made on the bearing function of the system, but the demonstrator shows promising results for actuating substrates with large accelerations and fast responses.