Commission THS11 Unmanned Aerial Systems: The Roadmap from Research to Applications KEY WORDS: Unmanned aerial vehicle, 3D point cloud, LIDAR, thermal infrared camera, near infrared camera, RGB camera, building inspection ABSTRACT:Conventional building inspection of bridges, dams or large constructions in general is rather time consuming and often cost expensive due to traffic closures and the need of special heavy vehicles such as under-bridge inspection units or other large lifting platforms. In consideration that, an unmanned aerial vehicle (UAV) will be more reliable and efficient as well as less expensive and simpler to operate. The utilisation of UAVs as an assisting tool in building inspections is obviously. Furthermore, light-weight special sensors such as infrared and thermal cameras as well as laser scanner are available and predestined for usage on unmanned aircraft systems. Such a flexible low-cost system is realized in the ADFEX project with the goal of time-efficient object exploration, monitoring and damage detection. For this purpose, a fleet of UAVs, equipped with several sensors for navigation, obstacle avoidance and 3D object-data acquisition, has been developed and constructed. This contribution deals with the potential of UAV-based data in building inspection. Therefore, an overview of the ADFEX project, sensor specifications and requirements of building inspections in general are given. On the basis of results achieved in practical studies, the applicability and potential of the UAV system in building inspection will be presented and discussed.

No abstract

No abstract

Synopsis.-The potentiometer principle is well understood. in unshielded form to about 66 kv. and in shielded form to about Its application to the determination of the ratio and phase angle 33 kv. The paper describes a shielded potentiometer for 132 kv.accuracy of potential transformers is not new, but has been limited which is designed for ultimate extension to 220 kv.A potentiometer was desired, which would (1) cover signs the range from 6.6 to 132 kv. at first and to 220 kv. by s . _________~~~~~~~~c. Transformers rated between 6.6 and 44 kv. in

Synopsis.-The application of Y-connected transformers to three-pated from the suppression of the third and its multiple harmonics, phase, three-wire systems, in such a manner that the third and may not be generally appreciated, so this paper outlines experiences its multiple harmonics of the exciting currents woutld ordinarily with two such applications. The peculiar and dangerous "saturabe suppressed, is not in aceordance with the best practise. How-tion phenomena" obtained and the methods of preventing their ever, such applications of grounded-neutral, Y-connected potential occurrence are described and considerable data thereon included.transformers, particularly to temporarily ungrounded systems, The phenomena are discussed from theoretical standpoints in have been made for relaying and other purposes. The resulting companion papers by A. Boyajian and 0. P. McCarty and by complications, which are of a different nature than would be antici-C. W. La Pierre.2. The abbreviations L/L for "line-to-line" and L/N for