Recent content by Talisker

Hello gmonati. Many thanks for your reply. Judging by how hard I found it was to get a spare battery you should have no difficulty selling yours. I have found one already and now need to see how to close down my request.

Many thanks for the alert. Unfortunately I get the message 'Sorry, letgo is not available in your country', so I can't see it. However, sending batteries internationally seems to be quite a hassle, with more regulation and costs, so at least for the private individual best avoided.

Have you a little used, genuine DJI, battery for a Phantom 3S for sale? Decent price paid. Must show all cells in good order. 20 or fewer charge cycles recorded. No crash history. Purchaser in UK.

I've just read the beginning of this thread and without looking at my stills in detail I'd say that my P3 camera has produced remarkably good results without any post-processing but my top-of-the head comment is that 100 ISO is too slow a speed to set. Although the drone may look pretty still...

2) I'm sure the IMU works very hard to keep the bird steady both when hovering and moving but accelerometers measure only change in speed and gyros measure change in orientation. Both position and orientation need something to define their zeros so that the changes can be applied to a known...

Yes, electronic tiltmeters have been around for quite a while. I first came across Rank, Taylor & Hobson's "Talyvel" in a workshop context in the 1970s but they weren't even new then. They were much easier to use than the traditional accurate spirit level, and more sensitive. The Wikipedia...

Returning to the original piece that kicked off this thread (http://homepages.abdn.ac.uk/nph120/meteo/DroneFlight.pdf) version 2 has appeared that does not make the assumptions highlighted in post 22. There is some difference in the power figures from the earlier version but the return to home...

In respect to post #17, what is minimized is the energy required to travel a given distance, not power (which is a rate of energy production). The article does find the speed that minimizes the sum of both the energy required to keep the drone aloft while covering this distance and the energy...

Looking back at sar104's comment that "The article that you linked has some serious issues. At least one of the basic results is demonstrably incorrect - that the aerodynamic force on a moving Phantom is downwards and increases monotonically with airspeed" it seems to me the article did not say...

Interesting discussion. The original article does give the function for the energy used to travel a given distance that was minimized to produce the answer of about 10 metres per second as the optimum speed. There is now a supplementary paragraph showing the energy usage graph and a discussion...

What do DJI say about the optimisation of RTH speed? Given that the battery running out is by far the biggest hazard to a drone, there’s not much else they could have set it to other than using the minimum energy to travel a given distance. It’s not that easy to check in reality, since...

Give a drone to a physicist and he/she is likely to want to know how it works. Those with some science background might like to see http://homepages.abdn.ac.uk/nph120/meteo/DroneFlight.pdf. The article includes power consumption for hovering, rising and moving forward, estimated from mechanics...

I was about to click 'no cracks' and had a close look and found one on my P3S almost vertical just above a rear leg near the battery compartment. There's no visible opening' of the shell and as far as I know it hasn't had any effect on the flying but I'll now keep an eye on it.

I've done most of my flying over the sea from cliff-tops. Grey sea, grey clouds - it's easy to loose sight of the drone at a few hundred metres distance unless you know exactly where to look. Are these lights visible during full daylight at this distance? The drone's own lights certainly...

A co-incidence or what? I was a few miles from Aberdeen when it happened to me. Can't check if it cleared itself for another week. I did check the drone itself to see if any software had got loaded onto it and didn't find anything. Talisker....