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Is it possible to do waypoints at an altitude of 6 ft?

Discussion in 'Pro/Adv Discussion' started by el cuajinais, Feb 12, 2016.

  1. el cuajinais

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    I have a P1.0 and am considering trading for a P3A over the weekend. I intend to use it for a shoot pretty soon. I’d like to use waypoints at low altitude. Is this possible or do you need to be at least 30 ft high for waypoints? If the DJI app does not allow this, is there an app that does?

    Also, when controlling the camera in manual mode while the P3 is running the waypoint route, can I make the tilt control be on the left stick so that the left stick controls both tilting and panning? Or is the tilt still controlled on the “wheel” controller?

    Thanks in advance.
     
  2. DroneDestination

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    -Nope, must be 30ft or higher for DJI GO, not sure about Litchi, Autopilot or Vertical Studio
    -Gimbal is always controlled by the wheel
     
  3. Buckaye

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    The big problem (besides not being able to do it under 30 ft) - is that if you were that low to the ground and you even experience a little uphill action... you could easily crash into the terrain. I set my ground station one time to 30 ft - and even at that height I didn't take enough into consideration the change of terrain height and vegetation in the area and ended up crashing (softly) into some very tall weeds.
     
  4. Baldo Mero

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    Autopilot allows a minimum of 5m on waypoints when using GPS as reference and less than that if you use barometer and configure this minimum heigth manually in the settings.... risky but possible. As for the camera control, I do not think that it would be possible. But you can set the focus triggers in the mission and probably obtain much smoother results than manually.
     
  5. el cuajinais

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    This is no longer a concern since now you need to fly to each location to set the waypoints. The only concern would be the precision of the altitude control, and the effect of wind gusts. Both are risks I am willing to take if there is an app that let's me do this. Can anyone else chime in?
     
  6. rhoffart

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    You can with Litchi. It will allow a negative altitude if you need.
     
  7. el cuajinais

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    Awesome. Have you ever tried this yourself? Have you ever done a waypoint route at, say 10ft off the ground?
     
  8. Shammyh

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    Waypoints with Litchi are possible at that altitude, but it would require careful planning, and is something I would generally advise against, especially if you have to come here to ask if it's possible.

    I'd suggest flying through the route manually first, and dumping your controllerside logs to verify that the heights you want to program are reasonable, especially given variations in terrain.

    As to camera, when configured correctly with Litchi, you can use the yaw function while the craft is following the waypoint route, but the camera will still need to be controlled via the wheel.

    Also, be ready to flip to Atti at any time to stop the autopilot if required.

    Also practice, practice, practice. Maybe do a first run with an extra 10-20 ft of altitude, then try another run at a lower altitude after.

    Oh and finally, the barometer (which determines the height value the P3 will be following) has about 1-3 ft of variability in its measurement. So personally, id set at least a 5 ft margin of error above whatever my target height was.

    All in all, this is a pretty good way to crash, but if you must do it, follow all the advice in this thread, and your chances of success will be improved.
     
  9. lookin4pain

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    Guessing he's not filming roof tops and trees, maybe chasing an R/C car or following his kids playing with a hockey puck.
    Maybe some advise about vps, or is that limited to pro



    Sent from my iPhone using PhantomPilots mobile app
     
  10. el cuajinais

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    I’m a very experienced pilot. The reason I’m asking here is I’ve never flown a P3; and the only time I came across someone flying one, the pilot know only about 30% of all the features available on his P3. I want to track an actor in a flat, open grassland with the odd tree here and there. That 1-3 ft variability of the barometer is great info to know. Thanks.
     
  11. SteveVaus

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    Litchi will allow you to program such a mission but I've found Litchi to be 5-8' "sloppy" with respect to altitude. No big deal up high - down low... potentially a drone breaker.
     
  12. autoflightlogic

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    Autopilot will allow 1m minimum. As for the camera control, you can use Joystick Focus Strategy to have control of the gimbal with the left and right joysticks.
     
  13. Luis V.

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    Reviving this thread as I had a couple of similar questions.

    With Autopilot are there general minimums in terms of distances and altitudes? I.e. Is that 1m mentioned above the minimums on all the modes?

    If "no" on the above...

    Does anybody have experience with the Orbit mode? For example, with DJI Go we have a 5m minimum on altitude and 5m minimum radius. Is that the same on autopilot?

    Similar question. In zip line mode, is there a minimum altitude?

    For background, I am planning on using the drone for a number of auto shots and videos. Shooting at a 15' radius and altitude in the POI mode (DJI) it's a bit distant. I'd like to get shots that are tighter. For example, a zip line shot focused on the front bumper emblem as I pass the front of the car. Tried that with some manual piloting and it's not as smooth a motion as I'd like it to be....
     
  14. Baldo Mero

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    No limits with autopilot, there are pre-set minimums in the settings but you can change those to anything >1m. Minimum radius in orbit I have not tested extensively, but it is not practical: if too small the craft does not really orbit but jerk around. One thing to consider: if you plan shooting at heights below 5m you should preferably use a control device with barometric altimeter (>iphone 6 or ipad with wifi&data) and calibrate the height upon engaging the mission, particularly if the terrain is not perfectly flat.
     
  15. happydays

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    I know that in orbit POI mode using GO, once the mission is underway, you can lower the altitude below 10m to achieve a corkscrew effect.
     
  16. autoflightlogic

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    Yes, and additionally you can actually fly the aircraft to any location, including an altitude beneath you, and then engage Autopilot while specifying that the current aircraft altitude be used as ground level during the engage sequence. This means you can fly at "negative altitudes" relative to yourself, but be very careful.

    Right, because the GPS accuracy is +/- 4m, so flying 15 ft away from something is basically within the margin of error.

    This is only if you plan to be moving and you want the aircraft to change altitude with you. If you are standing still, you don't need to have a device with a barometer because you can answer the questions in the engage sequence so as to just use the aircraft's barometric altitude (i.e. Fixed Operator).
     
  17. Luis V.

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    Thanks for the reply... The issue with the orbit minimums is more on the altiude and not radius. 15' away is fine for a radius as I am flying around a car so I'd need around 20' typically. Most of the cars I will be shooting are in the 15 to 20' length range. However, the orbits are far nicer at altitudes in the 2m range as opposed to the 5m range.

    I have been using the iPad Air for my flight control. It is a WiFi/4G unit. I was not aware that they had barometric altimeters. I assumed they worked with GPS for altitude. I would assume the calibration is done in conjunction with Autopilot. Is this correct?

    Interesting. This can come in handy for some shots in the mountain areas. For example, a vertical panning shot while I have a group of cars at an overlook on a hill side. I can work with that.... cool.

    Most of the shots I am talking about (cars) would be done in some parking lot, open field or at a track and in South Florida. Pretty much as flat as it comes. However, good to know when I setup for some shots in other terrains.





    Thanks everybody for the quick replies!
     
  18. Baldo Mero

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    Yes, latest apple devices include the barometric altimeter in the WiFi/data versions so you are OK if needed. The calibration option appears in wizzard within autopilot upon engaging the mission, and as replied by flightlogic it comes handy if there are going to be changes of ground altitude during the mission (e.g., tracking or following moving subjects at low altitude). From what I understand of your intended use you can find Autopilot quite useful and no limits on height during automated flight modes.
     
  19. Kimosabe

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    I recently was trying to make a selfie with my phantom 3, when I noticed the Displayed altitude had significantly deviated since the start of my flight. I started the flight using The Go
    App, then flew a short mission using Litchi, and switched back to the Go app while I was hovering at eye-level. I noticed the altitude displayed on the screen of my iPhone was 8 meters. In reality the drone was hovering at 2 meters. I recon that if i had sent the bird on a waypoint mission with waypoints with an altitude lower than 8 meters, it would have crashed. Would de VPS unit do anything to prevent this? Did anyone else experience a drift in the altitude? Could the drift be caused by switching between apps? Or does the the height information come directly from directly from the bird.

    Cheers

    Thijs


    Sent from my iPhone using PhantomPilots mobile app
     
  20. Baldo Mero

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    Some drift on barometric altimeters is quite normal, even in high-quality ones. They can be affected by temperature and high speed/wind. You should never trust the telemetry readings to be accurate enough to rely that you won't crash if your margin is less than 5m. IN those conditions you should rely on visual estimation and manual piloting, or at least be ready to take over. I suppose that if you change apps during the flight the telemetry drift can be accentuated as each app can reset the telemetry with the current value reported by the craft upon launching. Personally if I am flying at 2-3m height I don't even look at the telemetry.