Advice on purchase? (I'm doing a protogrammetry project)

Hi all,

I am new to to the programmable UAV world but I am very interested to learn what ever I need to to do a project. But first I need to know what to learn. I have been reading different forums and brands but I want to seek some advice on what I should be looking at:

I’m planning to develop a series of tools, to use quad-copters (less maintenance than copters) to photograph buildings automatically. My goal is to make this technology as simple as possible for the largest user base, even end consumer. The photos being processed can be combined with protogrammetry algorithms to obtain a 3D model, imagine a building scale 3D scanner. You can see some here.

(Not my vid)

Here are some research work done in MIT about mappping buildings (you can view the 3D models in browser: … index.html

I want to start with some tested and proven systems, Arducopter seems to be a good candidate for the following task:

  • I will need a front camera on a UAV, I have a GoPro Hero2, so I believe I can mount it on any copter that can fly.
  • I want to fly this copter in mainly 2 mode. A pre-planned flight path (auto and step by step) and have manual control at anytime I pause the flight plan. I do not need full autonomous flight.
  • I will want real time video back from front camera.
  • I will want real time high-res images sent back to computer or tablet.
  • I will want to be able to do more detailed pre-plan flight path, I’m very happy to see auto WP in Mission Planner but I need to plan a lot of still shots along a flight path.

I assume ardupilot is mainly relying on MavLink and it can handle the above mentioned items? Correct me if I’m wrong:
Sending: landing, lift off sequence, target GPS location, heading, manual pilot instruction, camera shutter.
Receiving: Real time video, high res image, navData. (How can GoPro stream with the MAVLink, or is it not necessary?)

I see that Mission Planner is open source, and written in Processing. I think I will be able to learn enough to write some additional feature to do more advanced WP. But I want to get an idea what hardware I need to buy and what technology I should be looking at.

Thanks in advance.

Hi Victor. You probably get responses from many far more knowledgeable than I, but I’ll give you my take on your queries.

There are many airframes that can provide the basic functionality you need. You might be able to get by with a quad, but if your equipment gets heavy you could go to a hex.

You can set up preplanned flight routes in Mission Planner and step through them using the APM telemetry setup. One thing to be wary of is GPS accuracy. I don’t know how close you need to be to structures to do what you want, but there may be a considerable variation in coordinates you pull off an aerial for making a flight plan and where the surfaces of those structures actually are in the field. Also the buildings themselves can block some GPS satellites and the flight modes you need absolutely require a good GPS lock.

It is possible to get real time video out of a GoPro (standard definition only) but it’s not widely done. There are sometimes issues with image latency and occasionally GoPros can shut off or lock up, thus cutting your video feed. Most people seem to prefer the reliability of a small, dedicated FPV camera. Also, GoPros, or other cameras for that matter, don’t stream within Mavlink. They must have their own transmission equipment. Mission Planner does offer the ability to merge that video output into the data display.

Real time HiRes images are a challenge. Normally available FPV transmitters are only standard definition. Depending upon your range to the copter you could try and implement something using WiFi, but now you are in very DIY territory.

Hi Victor,

Why do you want real time images back? They don’t help with the end product and make your machine more complex and expensive. Don’t be seduced by how many folks think it should work.

I took this with a point and shoot just slung between some hex arms and hand flown.

Its not brilliant but it works, … 4fe49ec986

New flight modes that will arrive with Pixhawk in particular spline navigation will make this task much easier

You should also look at this thread, … -the-model this task is our current competition.