Shapeways Parts - Second Coming of the FPV Undertray

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So for those that didn't see my first post about it you can find it here: viewtopic.php?f=4&t=999
I basically dusted my old 3D Cad pacakage off and got to designing for the Phantom.

Today I took delivery of the revised version of the Custome FPV Undertray as well as a few more designs that I have created.

This will be a long *** post I hope it will be worth it for a bit of feedback.

EDIT: Pic of it during a succesful flight test


All that I had made this time can be seen here:



And this is a basic overview of what they all are intended for:



This is with the Phantom fully loaded with it all! I will explain each item over the course of this post:




So what exactly is all this?...

- Revision 2 of the custom Phantom Undertray with TX holder (designed around the Fatshark 250mw TX). 22 grams.
- Dual battery frame (holds a second battery to the undertray or can be velcro strapped) - 7 grams
- Stand alone TX holder (can be velcro strapped or velcro adhered) - 8 grams
- Fatshark Filter housing (the small filter that comes with the Predator V2) - 4 grams
- GoPro Hero3 frame - pretty much the same as the one they sell but - 4 grams
- Gopro to Hotshoe mount (allows fitting of any camera with a 1/4 inch tripo thread such as the Drift HD or Contour).

Revision 2 of the Custom FPV Undertray.

Shown below is the transition from Sandwich box cut out concept to final strengthened design:





The revision basically added strength and backbone to. A 3mm edge and 3mm support frame makes it a lot more rigid than the MK1. I also shaved some deadweight grams from the TX holder so the MK2 is stronger but lighter (and cheaper to build!).
Mk1 (seen below on the left) was a little too flimsy. I made the Mk2 stronger. Note the extra fat saving holes all over the TX. It is still very solid but lighter. You can also see a groove in the TX holder's door which holds it nice and snuggly.


Mounting to the Phantom:
For those that didn't read my first thread, the undertray mounts via 4 x 25mm male to female brass hex spacers which replace the innermost screw of the landing legs. They simply screw into the existing threads and then the stock screws are then reused to secure the undertray (shown here with the Fatshark filter housing mounted... explained later on):


TX slots in here as before. The door is secured with 3mm nut and bolts:

Slight change to improve how the plugs slot in:

Cables route through the holes:


Fatshark Filter Housing

The filter that comes with the Predator V2 was less 'lumpy' than the TX and had a flat surface to stick velcro too but it bugged me. So I came up with this:





I created a slot for velcro straps to hold it to the undertray. You can still use adhesive velcro too.



Strapped onto the slots in the undertray:



Battery Tray

The idea of this is to house a second battery under the Phantom’s belly that can be connected in parallel to another battery in the usual slot.
The batt slots into the cradle:

The cradle has a sprung end to allow a tight fit:

A securing pin then slides into its slot and is held by a securing pin. This looks less solid than it actually is as the nylon has plenty of give.

The cradle then mounts to the undertray. There are grooves in it to stop it slopping around but it can also be turned upside down to mount to other trays with slots.



Standalone TX Holder

Nothing too complex here but being that I will put these for sale on Shapeways I thought people might like the option to house the TX but not be tied to buying the whole undertray.
This is the same design as the one that is part of the undertray but it incorporates a flat top for Velcro adhesive mount and a slot for Velcro strapping.




GoPro Frame

Simple, cheap, easy to use. I love GoPro's products and the Hero3 especially but in the UK £40 + £8 p&p for the Frame is an outright scandal. Granted you get two sizes with theirs but I got this made on Shapeways for peanuts and the Nylon is perfect for flexibility and best of all it is 4grams. I didn't really make it JUST for the Phantom but it is 10 grams lighter than the DJI mount and doesn't need a spacer for the Hero3






Hotshoe to GoPro mount

This was a design stemmed from a Drift HD owner but can be used on any camera with a tripod thread in it (within reason from a size/weight perspective!). It is basically a camera flash ‘hotshoe’ with a GoPro mount. For £2.50 on ebay you can by the converter (the black thing). This slots into the hotshoe and you simply tighten it down:





(no I won't be flying with that cam attached! :lol: )

Phew... that was a lot of organising to post! So thats it. I will take it out tomorrow and take some pics of it all 'in flight' hopefully.

I should note that the Phantom with stock battery, MK2 undertray + battery cage (with battery in it) + GoPro cage + Fatshark Predator V2 TX and Filter comes to 1170 grams so just under the weight limit.

All going well I will get these on Shapeways for sale this week (flight test pending) in case people are interested in any of it.
 
I think this is a very valuable contribution to the Phantom flyers community. I use a landing leg bracket set fron simonsays via shapeways and I am very impressed with the strength of the plastic material. Perhaps you might like to combine several of your designs into a complete landing leg replacement for the stock dji ones which are the weakest part of the phantom design. The opportunity to radically improve the looks alone is worth the effort. I would certainly buy one if you made it. I am heading over to shapeways now to look at your things.
 
howardmaryon said:
I think this is a very valuable contribution to the Phantom flyers community.

Thanks howardmaryon... very kind words! Its been a lot of fun seeing it develop i must say!

I went out and flight tested earlier (some pics below). Considering it was fairly windy it worked out way better than even I had hoped. So happy with it that I have just now set them all for sale on Shapeways. Search 'd3wey' on their site and you will see them all. I will post them in the for sale section soon too.

It is a shame I cannot get the price down on them a little but it is just cost of Shapeways modelling. Safe to say even with a mild markup I won't be making any real money from it (Especially as I will happily give 5hrs of my time up tweaking lol).

As for the landing legs - yes I might take a look at this. Simensays' design is really great but what I am working on is a quick release system for the existing legs. Personally I'd love to be able to click the legs off and get the whole thing in a back pack and the legs stop you from doing this. The issue is keeping the cost down. I know I'd not want to spend more than $50-$60 on something that is not tried and tested. That said I am not doing this for profit, just for fun really. Keep the suggestions coming guys!

Pics of the test flight:






 
Remarkable!

I've just added the Fatshark Predator FPV to my Phantom and was quite unhappy with the lash up of Velcro and doubleback tape required to attach everything. Your add-on components not only match the Phantom's "look & feel" but will greatly simplify installation of FPV.

I'm also headed to Shapeways....
 
GearLoose said:
Remarkable!

I've just added the Fatshark Predator FPV to my Phantom and was quite unhappy with the lash up of Velcro and doubleback tape required to attach everything. Your add-on components not only match the Phantom's "look & feel" but will greatly simplify installation of FPV.

I'm also headed to Shapeways....

Thanks Gearloose. Great to hear such positive feedback!!
I am sure some people see this as overkill for FPV flight but I love the neatness of it now. It has been really satisfying to see it all coming together (the white nylon is a bonus too as you say!). I really look forward to hearing from whoever might be the first to have one made for themselves.

To be honest I really wish I could get the price down for people who are interested in it. The only way I can do it is to shave more off it. I have developed a design that is cheaper but it means there will be no flat surfaces to stick on (just structural holes). It saves maybe €6 in cost ($10?) and is untested so I've not put it up fore sale as yet.
I am also hoping to make a version that will fit with Gimbals (it kinda makes sense to have one!).
 
I'm not sure if I need the full tray + TX holder. I don't have any plans to add a second battery but I do like the way the tray extends the position of the Fatshark transmitter. I'm wondering if the tray could be trimmed down a bit so that it holds both the TX and the filter but nothing else?

Or... could I mount the standalone TX holder and the filter holder directly to the shell with bolts, to make them as secure as possible? I now have both mounted with Velcro and find it difficult, especially with the filter, to easily grasp the filter and hold it firmly while plugging and unplugging the filter cable.

I'm getting more and more interested in a gimbal, which would apparently not work with the full version 2 undertray?
 
GearLoose said:
I'm not sure if I need the full tray + TX holder. I don't have any plans to add a second battery but I do like the way the tray extends the position of the Fatshark transmitter. I'm wondering if the tray could be trimmed down a bit so that it holds both the TX and the filter but nothing else?

Or... could I mount the standalone TX holder and the filter holder directly to the shell with bolts, to make them as secure as possible? I now have both mounted with Velcro and find it difficult, especially with the filter, to easily grasp the filter and hold it firmly while plugging and unplugging the filter cable.

I'm getting more and more interested in a gimbal, which would apparently not work with the full version 2 undertray?

All good suggestions and actually very easy to implement. I am just finishing pretty much exactly what you suggest. It is the tray without the overhang and no TX (but it has the slots for velcro and the cable tidy). I know the tray fitment is perfect now so making simple spin offs is easy. The only disadvantage is I can't afford to keeping making them for myself just to take pics of :lol: (seriously the margins in this are nothing!).
The overhang at the back keeps the Fatshark TX out of the way of the internals without being in the prop down draft. I'm not saying you will get any interference from the internal electronics but it is what Fatshark suggest so thats why I went that route.

Keep an eye on this thread and I will update it when I have finished the design(s).
 
tc tx3 said:
that looks great I have just ordered mine of shapeways yeah!

First man to take the plunge! I thank you kindly sir!

I am hoping the service you get from Shapeways works well. I can only say good things myself and they normally ship sooner than they say they will. PM me if you want advice on what spacers to buy (don't buy nylon ones. They are light but the threads are too weak). I'd love to see some feedback on here and pics when you get it too. Really really hope you are as pleased with it as I am :D
 
DeweyAXD said:
tc tx3 said:
that looks great I have just ordered mine of shapeways yeah!

First man to take the plunge! I thank you kindly sir!

I am hoping the service you get from Shapeways works well. I can only say good things myself and they normally ship sooner than they say they will. PM me if you want advice on what spacers to buy (don't buy nylon ones. They are light but the threads are too weak). I'd love to see some feedback on here and pics when you get it too. Really really hope you are as pleased with it as I am :D


yeah took your advise and bought some of the brass spacers off ebay, well 20 of them for $12.50 :lol:
 
tc tx3 said:
yeah took your advise and bought some of the brass spacers off ebay, well 20 of them for $12.50

Lol wow... well at least you will spares!
 
So today I managed to get 'some' footage of my dual battery test. I made it all the way to my test zone (a bloody great field) only to discover I had left the SD card for my good HD camera at home... joy! So the video is from an Iphone (make sure to up the settings to HD!).

[youtube]http://www.youtube.com/watch?v=B3NHwffnyeo[/youtube]

The video is less important than the results frankly. The test involved this setup:

1) Phantom
2) Fatshark Predator V2 TX mounted in Shapeways d3wey Custom FPV Undertray
3) Predator V2 Filter in the d3wey filter housing
4) Stock DJI Phantom battery mounted in the shell
5) Overlander 2200 mah battery mounted in the d3wey Battery Cage (secured to the undertray)
7) Paralel battery cable
8) GoPro Hero3 (Black) mounted in d3wey "Frame'ish" and wired to the TX via USB input cable

Total weight 1170 grams.

Apart from the hovering taken for the video the flight involved a couple of climbs to maybe 150-200 feet and then some fast maneouvres over the field. While i was using LOS to fly I had goggles around my neck and the kit was switched on. I kept fairly close to my location to see the battery status.

First Red Light: 12mins 32 seconds
Landed (manually) after seeing two flashing Reds for the first time at 14mins 20 seconds.

Voltages measured post flight:
Overlander 2200mah: Cell1= 3.71 Cell2 = 3.72 Cell3 = 3.72 All = 11.2v
Phantom Stock Batt: Cell1 = 3.69 Cell2 = 3.70 Cell3 = 3.70 All = 11.1v

The flight characteristics seemed aboslutley fine with all the weight. You can tell the Phantom is a bit weighed down but it was by no means struggling with turns, nor was it falling out of the sky at low thrust.
Interestingly after I had landed the green lights were still flashing so I clearly wasn't anywhere near the bottom of the scale and the voltages confirmed this (comments on these are welcome).
I have a GTU10 tracker that I will add for the next flight. It will take it over the 1200 grams (just) but I really don't think it will be an issue.

I was really impressed with this result. Almost amazed actually as I was expecting maybe 12 mins tops!

As for the rig itself, well that did really well too. The battery cage held very secure and upon landing it was still exactly where it started when i took off (no movement or sliding).

I should mention that a mod to the battery door was needed to make the parallel cables work. I will photo this soon (cut part of the sides off basically). This mod was also needed for me to fit my Turnighy 2250mah Nano-techs in (these do not fit in my current batt cage I should add!).

My Hero3's batt died at about 1 minute and I wasn't recording either (really didn't do well on the camera front!). No strange wobble was present via FPV goggles but I will do this again to prove the GoPro "Frame'ish" performs well.

Happy times! 12-13 mins of solid flight time is enough to justify wanting more range now.... Futaba 8j the next mod me thinks!
 
Count me as "impressed".

But, don't you think that most people are going to want to use a gimbal, which obviously puts the total weight into the obesity zone? For general FPV flying and filming, however, this set-up looks very attractive.

Have you tried drawing your batteries down to even lower voltages? If I'm correct, discharging to 80% will not appreciably shorten the life of the battery. With 11.1 volts, you're at 88%. I've been very conservative with flight times. My batteries are usually down to 11.3V, which is 90%. I'm thinking of decreasing the values in the NAZA Assistant and trying longer flights.
 
Very good points Gearloose. I fully agree that the gimbal situation is where people really want. I need to get my hands on some good pics of the Zenmuse mounted and see if i can design something that could work but weight as you mention might just make it pointless. Even with my rig you are looking at 1.35kg with dual batts + the new PMU + the draw from the gimbal.
I will be very interested in seeing FPV flight times with the Zenmuse. I can't image more than 6 mins tops with a stock batt and adjusted levels.

Speaking of levels yes i could lower them a bit and get more. After yesterdays test i think i can get a safe 15 mins in with little to no wind.
I have a 3.3v per cell buzzer which i will fit too. I have a couple of weeks of soon so loads of testing time available! You guys will be sick of me posting by the end of July probably :D
 

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