Vehicle Design of Tethered Hexaroters for Heavy Payload Applications

Abstract

This research addresses the vehicle design problem for industry class tethered hexarotor development project. Hexarotors are unmanned aerial vehicles of resent research interest due to their capability of vertical take offs, landings and hovering at specific locations. Tethered vehicles has the advantage over battery operated flights for not having the flight time restrictions. In existing tethered hexarotors the payloads are lower than 20kg due to the design and the weight of power conversion devices. This paper presents vehicle design and automated cable winding structure of new prototype of heavy payload type tethered hexarotor which is capable of carrying user specified data acquisition device mounted on vehicle weighing more than 30kgs and has capability to provide about extra 1kw power to operate in field operations where reliability is the key factor. The proposed vehicle design is compact, light weighted, aerodynamically and mechanically optimum to proceed to the actual vehicle assembly. The proposed automated cable winding structure makes the tethered system efficient and safe.

Overcoming the Challenges of Using Unmanned Aircraft for Bridge Inspections

“…al. connected to a 380VDC-to-48VDC and a 380VDC-to-24VDC power converter each for DC motors and autopilot, respectively [40]. Thrust test results indicated that using 29 x 9.5 in CF propellers, each motor produced more than 10 kg of lift at 80% throttle.…”

“…The reeling mechanism was automated and utilized a servo motor. The reel design included tension sensors to avoid excessive tension by retracting and loosening the tether when necessary [40]. A method of modeling a deployed tether was investigated.…”

Design and Implementation of a Tether-Powered Hexacopter for Long Endurance Missions

“…Tether-powered multicopters are able to extend their endurance to "near infinite" since the ground station is powered by the grid, a fuel generator, or a huge battery that contains much more energy than can be lifted in the air. In previous researches, a tether-powered multicopter can either be directly powered by a tether [16,18,19] or through an additional electricity converter installed onboard [17,20,21]. Usually, one with an electrical converter is able to achieve longer tether length than those being directly powered by a tether.…”