First of all some background...
Having spent a good 2 years playing about with an Skywalker, Ursus and a Canon camera running CHDK, and designing my own uav, which actually flew recently ,I have come to the conclusion that flying wings may just be the best type of platform for short range aerial mapping tasks to create DEM, DSM models for GIS purposes.
The Skywalker was okay (but quite fragile, and now in pieces!), but I think it is too small to fit a roll gimbal on it. And I've found that if pictures are taken on a slight angle, it is very difficult to use software to tile them up nicely. this is my best effort, but far from perfect. The roads on the right do not line up as the camera must have been on a 45 degree angle when the picture was taken. (click for larger resolution) - It was taken using an ixus80 attached to an URSUS Airframe
Realizing that I need to use an airframe that can accommodate a stabilized roll gimbal, i started to design and build my own twin boom design. It took 6 months from initial design, to first test flight. It has a wingspan of 2.4m - AUW of 5kg, and a flight duration of around 30 minutes with 2 x 5000mah packs. However it needs a heck of a lot of room to take off and land, something i don't have in the areas i need to take photos.
Picture of twin boom plane...
What are peoples experiences with using flying wings for this reason? I have the following types of flying wings, and wondering which one is the best to begin with?
I have been using the 60" wing to test the APM2 and 3dr radios. And was using the URSUS (now in pieces after a nasty crash!) as a test platform to practice with the Canon CHDK Kit.
Here's a few pictures of the wing and camera....(click images for larger version.)
My question is how straight forward do you think it is to fit a roll stabilized gimbal to any of the above airframes?
Some updates from my side:
- after playing a lot with Canon camera parameters I think that I have found the right values;
- cruise speed is around 65km/h;
- using a 2200mAh battery(only 1300mAh consumed) , 12 min of flight can be achieved, 13km total length.
I'm thinking to move to FX-61 wing (smaller cruise speed), anyone is using it ?
There is a group with it; mine is waiting in the box yet
Hope it's not too late :) , I have been using FX61 for mapping rainforest in Kalimantan (Indonesian part of Borneo) with the local community members. It performs very well for our needs. With our settiing (thanks to Nguyen, also in this DIY Drones forum) we are able to fly for nearly an hour (with 5,000 mAH 4S battery) bringin CANON S100 with CHDK cruising at 12 m/s (I guess around 45 km/h) at the altitude of 350 m AGL (at the moment no regulations / height restriction in Indonesia, but we definitely fly safe and always check and re-check again the commercial flight route in the area if available and so on). Let's say, in a week time of work, we are able to have around 5,000 Ha (minimum) of forest mapped by 1 Drone and we are going to go forward with this activities to register the customary and community forest for protection.
I hope it's useful.
Thank you for the info. It is not too late :) , now I'm preparing a wood board to make a better layout of the parts inside.
Can you please share your setup ( electronics , layout and the total weight ) ?
I had some difficulties in choosing the best place for the camera , I'm interested to see how you have mounted yours.
Thank you in advance.
First of all, I am sorry for not being able to provide you with layout of the part inside as I am now in EU and the drones are in Indonesia (but I will ask my friends there to send it, or you can check out the one of Nguyen. He put a thread on how he is able to fly 114 km with FX61).
I don't use 2 batteries (as Nguyen did) however I use this multistar high-capacity 3S 5000 mAh
I put the camera right at the CG of this plane (where the carbon spar is) so basically I made a hole (for the camera lens) there. The battery goes in front up to the end of the nose. ESC etc goes above the camera (where I also use a coroplast platform for the mounting (I guess it's probably the same idea with your wood board). The Motor we use is a 900kV motor.
With this setting, we are able so far flying for around 45-55 minutes (with such payload) and covering around 350-400 Hectares of an area to map (at the altitude of 350 m which is not illegal in Indonesia, of course after taking all the safety and security measurement).
I hope it's is useful for you for the time being. Just FYI, at the moment I am exploring (and modifying) Ansley Peace Drone (of Ed from Environmental Airlines) as the airframe. as I am working with the local communities where internet access (to buy airframe) is not always available. Also for curbing the cost. However, I see that there are a lot here using SkyWalker (including some friends of mine in Indonesia) as the airframe. 3DRobotics also has this 3DRAero which I think is affordable and fantastic.
During the past days I was thinking to add to my Skywalker X5 wing a bungee hook. This will give me the option to bungee launch the wing ( increase the safety during launch).
Based on your experience where the hook must be located (relative to CG ) ?