How well will a Hexakopter work at carrying an instrument payload suspended several meters below?
That is the question we will be trying to answer in the next few days as we get ready for some work for the Forest Service. The goal is to suspend an instrument payload several meters below the Hexakopter on a light-weight metal cable. The payload will weigh about 1.25 lb (0.56 kg) and needs to be far enough away from the Hexa to avoid the effects of downward prop wash. The payload and Hexa will be flying through smoke and we want the instruments to be unaffected by the Hexa itself.
I purchased some 1/16" (~1.6 mm) braided metal cable, some ferrules and some clips from the local hardware store to build the suspension system. I am going to use a 'calibrated' water bottle in place of the instrument payload for weight.
I am going to test:
1) At what distance below the Hexakopter will the effects of prop wash be non-existent / negligible? This will be done in the field by flying a Hexa above a pole with flagging tape on it. This distance will be referred to as X meters.
2) Can the Hexakopter fly in manual and auto mode with a 1.25 lb payload suspended at X meters from a 1/16” metal cable? This will be tested by performing take-off, manual flying, auto-hold, auto-waypoint flying, and landing with the payload attached. Results will suggest total success or a range of flight performance. It is expected that wind will play a significant factor.
3) How long can the Hexakopter fly with the payload attached? This will be tested by first getting the Hexa to altitude with payload and letting it to hover until the battery is at the minimum safe capacity. Then, with a fresh battery installed, it will be tested by flying a simple ‘back and forth’ route over the flight area to simulate increase battery demand. It is expected that there is a great potential for pendulum affects to occur during flight.
Stay tuned for some results!
UPDATE: I forgot, one of the main Hexakopter videos shows Holger doing his insane Hexa flying witha 1kg soda bottle suspended from below.