We have repaired a lot of DJI series drones in the last twelve months, ranging from the DJI phantom 2, P3 Advanced and P3 Pro all of the way up to the Phantom 4 and the Mavic Pro. All crashed in one way or another which in all honesty is a difficult thing to accomplish, however always possible!
This time we take on the mightily complex DJI Inspire 1 drone with its aircraft grade aluminium and carbon fibre chassis. This one was crashed and looked a little sorry for itself when it arrived at Spark Angels HQ in Kettering, UK, with a broken carbon arm and a very twisted chassis.
We purchased this DJI Inspire with a view to add it to our R&D schedule and a learning experience as we have recently finished our first DJI Mavic Pro complete rebuild after a watery end in a hot tub!
After dealing with DJIs smallest 4K quality drone our jaws dropped in awe as we unpacked this huge behemoth Inspire in its custom built case with dual controllers and spare batteries. Despite a broken carbon arm, it still looked like a menacing vision of the future and a prop from a Terminator movie!
I cut my teeth in the complex carbon fibre and exotic material world of Formula One with Red Bull and evolved into who I am now by working around obstacles by repairing Apple handheld devices with zero support or parts supply from the manufacturer. Our main ethos is to get stuck in and learn as we go and DJI drones are no different, not scared of the lack of instructions or spare parts we jumped straight in.
We could tell by looking at it that it wasn't a simple case of a broken arm and tweaked nose cone, oh no... and as we lifted it out of its tight enclosure we soon realised that there was something of great magnitude wrong with this fallen angel!
Never the less we started to strip the plastic body work off, exposing the skeleton, not carelessly I might add, watching snippets of people before us on YouTube and piecing the rest together ourselves we soon made progress.
One thing that immediately struck me was how beautifully engineered this drone was, everything looked like it had a purpose, all bolts carefully machined without an ounce of extra weight, made out of the highest grade stainless steel as not to corrode. Carbon work all very well trimmed and no glue spillage showing, this really was put together nicely, built to fly well and to fly fast!
Dismantling the left main motor arm from the Inspire was the main mission objective and after removing all of the obvious bolts we were left with some rather tangly wiring. Motor power, controls and antennas all in the mix most of which when given the extra confident tug exposed rather straight forward block or bullet connections, easily popped apart.
The only challenge came with the coax antenna cables attached to small rectangular aerial boards on the face of each motor leg. There wasn't much spare cable to play with and we managed to desolder them quickly knowing full well that if we melted the insulation then we would struggle to rebuild them and resolder.
Once desoldered we were able to withdrawal the cables and remove the offending broken carbon parts and start work on the main chassis. This exposed just how lightweight the arms were, it makes sense really as this thing has to get airborne but for geeks like us it was great to see the engineering that has gone into these parts.
The more that we dug down, the more damage was apparent resulting in a very bent aluminium frame and a bent pivot pin, the rest were just small components that wouldn't take much to replace or repair. We even found a slit in the main wiring which is something you really don't want to fly with as a short circuit could result in a downed drone and possibly even a firery end!
The keen eyed of you guys will see there is a feather in there too, this could very well be a clue as to why this bird was sent to the floor!?
With a table full of parts and a very sad looking DJI Inspire we set to work on the net to research into parts supplies, it didn't take long to realise that if you want more than the body shell or a camera gimbal then we would have to dig a lot deeper and possibly get a little "creative"... but hey! That is what it is all about, the thrill of the chase!
First stop with a very bent main chassis was an old friend and former colleague from Formula One who now specializes in all things fast and metallic and racing cars in general.
Tasked with attempting to straighten the rather twisted frame, I now move on to locate some of the smaller parts that we need and what may be one of the hardest parts to find, a replacement for the threaded pivot bolts for the landing gear.
Look out for part two when we will have an answer on whether the chassis was successfully straightened or we are looking for a new part...