Hi Everyone! I just wanted to share my bad experience with the DJI legs. I bought a few weeks ago, the addon landing gear for the F450 from DJI (Link here). The looked really cool :-D (at first). Look:
So I wen't to the park very happy to test my new altitude hold algorithm. After a while I have a bad measurement on the ultrasonic sensor, and the system performed a very hard landing. The result: the four arms of the F450 broke on the same place in the same way. I think this is due to a very bad design of the landing gear attachment.
Comments
I bought a couple of these although you could use just one to reduce weight. I felt two was a more solid option against impact.
http://www.ebay.co.uk/itm/171052371343?ssPageName=STRK:MEWNX:IT&...
I then attached the legs to the two plates added some Velcro to bind both plates to the DJI bottom plate as well as padding the two surfaces out to accommodate the screw heads on the arms and the newly attached legs.
I then added 4 bolts..two at the front and back of the three mated plates, illed out to size with nylon locking nuts.
Solid as a rock and hopefully no chance of the arms snapping under stress on impact...
Our version of the Arms and the New Landing Gear are superior in strength
www.uavobjects.com
wow.. sorry to hear/see that... I use them on my dji-F450, I thought they were fantastic, I have had a dozen flights or so on them and some ~1ft off ground landings. So far so good, I just love the look and truly logically what I feel to be a good fit. I find the other landing extensions would put too much force if you were to hit the ground hard. Then again, what do i know. I have a solid skid for my DJI-F550 Hexa. I just didn't feel that these landing arm had enough for the hexa.
Yeah those rctimer ones are the DJI, One of the guys here at the office tried them out on his, same big issue, they put crazy stress on. I also tried these carbon fiber that have two bolts that go on the bottom of the feet. We have been doing more acro so to save the arms we removed all the legs, it helps. I switch to the 3D Robotics frame for the APM, besides having more room to mount, nice standoff platforms to organize, it seems to take a beating much better.
Wow, that's a bad design. :rolleyes:
Are they the same as these?
http://www.rctimer.com/product_966.html
If you could drill holes and attach with 4 screws, that would be way better.
I am using HK600GT landing gear on my F450. The gear is not nearly good enough for a 600 heli (flexible plastic) but perfect for the 450 quad. LOL.
I fly these landing gear that I bought off of Ebay. They zip tie to the end of the gear and are crazy strong. The best part is they have a big foot to help in landing on soft ground and grass.
The original arm's design (the bottom) was never intended to handle a hard impact. Although DJI did offer that LG, but the connecting part of the original frame is weak.
Wow. Must have been a pretty hard landing to break all four arms.
I thought using only two screws to hold the new LG in place was a bit odd and did not allow the stresses to distribute over the plate.
Sad to see this.
-=Doug
Very Interesting, I use both an F450 and F330 and the arms wand normal landing tabs have prevented damage on many very hard landings.
Clearly these legs place very high stress on the arms when landing abruptly.
It looks like the landing legs bent the edge of the bottom plate up and in popping the PemSert type press nut fittings right through the plastic of the arms.
Clearly they put too much torque on the bottom plate in a hard landing.