Phantom 4 Active Tracking explained and tested to the max!

Discussion in 'DJI Drones' started by Sara, May 11, 2016.

  1. Sara

    Sara Drone Minds Presenter/Pilot

    Sep 9, 2015
    246
    58
    28
    Female
    York, UK
    Active Track function is extremely easy to use and we wanted to test it to the max! Over a period of few weeks we managed to find 12 different objects. Aim was to see how well the phantom 4 will perform with things that vary in size and colour.

    As you can see in the video..some objects like the ferry boat, small kite and even another drone were out of range and in the case of tracking the phantom 3 there was not enough contrast between the drone and surrounding environment for it to distinguish it. Therefore bright-coloured balls and me running across the moors in the purple top created a successful track. However I was flying quite close to the soccer ball (its movements appeared even faster) and kicking it meant losing it out of the frame, or it was simply too fast for the drone to keep up with it. Fast and small objects will therefore be more tricky for the drone to follow.
    smaller banner.jpg
    You can still operate the drone during active tracking, for instance moving it to the right and left will make the drone rotate, just like the POI (orbit) in the Phantom 3, and you can also change the altitude.

    The minimum distance from the subject, its size, colour and the surroundings are all factors determining how well the tracking works, but it’s a big improvement from what the Phantom 3 has to offer.

    DJI_0407.00_03_28_06.Still001.jpg drone-intro.00_02_36_02.Still002.jpg man with balls and phantom (1 of 1).jpg
     
    Seafax likes this.
  2. rhsant

    rhsant New Member

    Jun 2, 2016
    1
    0
    1
    Male
    Hi Sara! That's a really good video. I'm new here, I do drone research and I've worked with vision-based tracking a little. Thought I'd weigh in with some technical detail here.

    Most tracking algorithms will first identify distinctive visual features in an image (it could be a corner, it could be an edge, it could be a blob of colour) - for example, when you select the area you want to track on your P4, it would identify these features for you in the area you choose. Now once the drone starts moving, the tracker tries to match up the features you had originally detected with the features you might see in the current image by searching within a neighborhood of the original features. (Remember, the drone is moving so your features will have moved too!). So, if your features are moving too fast, or your features aren't distinctive enough, or they've changed illumination or been hidden behind other objects, the tracker might end up losing them.

    Your analysis of what works and what doesn't is spot on! I think the P4 has a really good tracking algorithm given the fragility of detecting these features :)
     
  3. Sara

    Sara Drone Minds Presenter/Pilot

    Sep 9, 2015
    246
    58
    28
    Female
    York, UK
    I'm sure active tracking will get better and more sophisticated. Thank you for your further explanation it clears up well why our test failed on some of the objects. Overall all I'm still impressed with how it works, though should try to use it more in day-to-day flying.
     

Share This Page

About Drone Minds

Drone Minds is a forum for users of all types of drones and all skill levels..read more