XAircraft X650 build thread

[walkerinerie]

Slowly got mine back in flying shape. Once I got new landing gear replaced, I noticed one of the arms was broken. Anyway, it seems to want to just flip over as soon as it starts liftoff. Maybe the maimed rotor blades aren't helping. I'm replacing those tomorrow. I'll hook it back up to the computer, check it out and maybe give it a spin tomorrow if the weather is good.

 

[Bartman]

walker,
good luck with it. it isn't just yours that wants to flip over at takeoff, they're all like that. I changed my props on Tuesday to 11"x5" Graupners and it doesn't try to flip itself with them. It'll get light on the gear and just sort of tiptoe around. It also helps to have some weight in the airframe like a 5000 mah battery or a block of wood in the camera mount.
I need to update this thread as I've been tweaking and changing things to get the quad as ship shape as possible so when the next round of firmware is released I'll know what I have and how much of an improvement the firmware provides.
Right now I've got the wobbles but I tweaked all my props and how they're mounted, I've restacked my electronics and recalibrated my AHRS so now I just need a calm day to fly. I'd fly inside but I can't afford to ding a wall and possibly wreck again so I'll have to wait.
Let us know how things go Walker. If you're not sure of something, don't fly and see if we can help.
Bart

 

[walkerinerie]

All,
Good news/Bad news! I got out and flew a couple of days ago. I'm still trying to master basic flight but getting better! Some of those online videos make it look so easy! I noticed before that I had way more control than I needed so I dialed back the transmitter sensitivity to 75%. I figured with that and hover mode it should be easier. After a few flips and landing in the bushes, I made a couple of good flights around the yard. The "unfortunate incident" then happened - I set it down in the back yard, happy that I hadn't crashed and was going over to pick it up. I turned off the transmitter (is this is a big mistake or are my electronics just messed up) at that point the quad took off at FULL power and made a beeline, 15' off and parallel to the ground, directly at my house (and thankfully not my neighbors or persons) and crashed at full speed into my deck door. If I had a video it would have been epic! Am I not to suppose to turn off the transmitter until I switch off the battery on the quad? One other question, I was watch one of the chinese videos doing static tests and his controller had the throttle and roll on the same control stick and mine is setup with the throttle and yaw on the same stick. Is one of these a standard or is it personal preference?
Someone is making money keeping me in spare parts! I bought some 2mm+ Lexan panels at Lowes the other day. I want to see if I can cut it easily for landing gear - it claims to be almost unbreakable! We'll see!
Walker

 

[Bartman]

walker,
that's a killer feeling, isn't it? mine fell from about 150 ft and it was going for the neighbor's roof but bounced along in the front yard. wherever you have electric motors it's best to unplug their power before turning off the radio and removing any motor control signal.
also, the x650 has the option to turn the motors on and off like Mikrokopter does it. it's somewhere in the programming (i can look later if you don't find it first) and it enables you to turn the motors on and off with positioning of the left stick.
as for the functions of the left stick there are mode 1 and mode 2 radios. most radios sold in North America are mode 2 with throttle and rudder on the left stick.
sorry about your crash but it sounds like you're making progress. keep it up.
bart

 

[RTRyder]

All,
Good news/Bad news! I got out and flew a couple of days ago. I'm still trying to master basic flight but getting better! Some of those online videos make it look so easy! I noticed before that I had way more control than I needed so I dialed back the transmitter sensitivity to 75%. I figured with that and hover mode it should be easier. After a few flips and landing in the bushes, I made a couple of good flights around the yard. The "unfortunate incident" then happened - I set it down in the back yard, happy that I hadn't crashed and was going over to pick it up. I turned off the transmitter (is this is a big mistake or are my electronics just messed up) at that point the quad took off at FULL power and made a beeline, 15' off and parallel to the ground, directly at my house (and thankfully not my neighbors or persons) and crashed at full speed into my deck door. If I had a video it would have been epic! Am I not to suppose to turn off the transmitter until I switch off the battery on the quad? One other question, I was watch one of the chinese videos doing static tests and his controller had the throttle and roll on the same control stick and mine is setup with the throttle and yaw on the same stick. Is one of these a standard or is it personal preference?
Someone is making money keeping me in spare parts! I bought some 2mm+ Lexan panels at Lowes the other day. I want to see if I can cut it easily for landing gear - it claims to be almost unbreakable! We'll see!
Walker

Your radio should be capable of setting a failsafe mode, it sounds like that needs to be done. Failsafe is usually set to where the control sticks are when the binding is done between TX and RX, or if not set it's usually something random like full throttle which would explain what happened in your case.

If you rebind the receiver with the throttle all the way down it should make that the failsafe position so if the RX loses the signal from the TX, like it does when it gets switched off, the RX will default to the failsafe setting of no throttle. The only instance where this won't work is if the flight controller board also has a failsafe mode that can be set or ignores what the RX is telling it on loss of signal although the last part is unlikely to be behavior that anyone would leave in the programming, but you never know.

Ken

 

[Bartman]

ken,
you're right about setting failsafe stick positions. with my JR it gets done when the satellite is bound to the transmitter.
as for the switching function of the XA with the motors, if the motors have been turned off (left stick full back and to the left) after a flight and then the transmitter is turned off, the motors won't turn themselves back on if the battery power is still available even with the failsafes. in this case you'll have protection with the failsafes being set up but you'll still have zero motor action if the battery is connected and the radio is turned off.
i'm very tired and probably not making much sense but maybe i made my point?
bart

 

[RTRyder]

ken,
you're right about setting failsafe stick positions. with my JR it gets done when the satellite is bound to the transmitter.
as for the switching function of the XA with the motors, if the motors have been turned off (left stick full back and to the left) after a flight and then the transmitter is turned off, the motors won't turn themselves back on if the battery power is still available even with the failsafes. in this case you'll have protection with the failsafes being set up but you'll still have zero motor action if the battery is connected and the radio is turned off.
i'm very tired and probably not making much sense but maybe i made my point?
bart

Makes sense, the KK and Hoverfly boards both have the arming feature in firmware, motors will not start until board is armed, usually throttle stick down and to the left or right or both in the case of Hoverfly. If you disarm the board on landing as you noted, motors will not start regardless of what happens with the TX.

Ken

 

[brendonvz]

I'm rather new to it all, we kinda old school new.... I hade no problems with the build thus far, but if there's anyone out there that can tell me how to connect my AR8000 receiver (DX8 transmitter) to the XR650 ? I just need to know where to connect the power as the receiver doesn’t have any power input ... back in the day my receivers had a power supply, and help would be greatly appreciated. Thanks

 

[RTRyder]

I'm rather new to it all, we kinda old school new.... I hade no problems with the build thus far, but if there's anyone out there that can tell me how to connect my AR8000 receiver (DX8 transmitter) to the XR650 ? I just need to know where to connect the power as the receiver doesn’t have any power input ... back in the day my receivers had a power supply, and help would be greatly appreciated. Thanks

Most all of the flight controllers for quads provide power to the receiver across the interconnection wires from their own 5 volt circuits or pass through from the ESC battery eliminator circuit. I don't own an X650 so I can't say for certain in that case but I don't see it being any different than any of the other brands out there. Plug the RX into the appropriate ports to the flight controller and power it up with the props off, you'll likely find the RXC has power and everything works.

Ken

 

[Bartman]

Brendon,
Ken's right. There is no specific power input to the receiver. The receiver gets power from the flight control board via the multiple servo type wires that come with the kit and run between the receiver and flight control board.
Bart

 

[brendonvz]

Thanks very much indeed, I'll give it a go and let you know.

 

[brendonvz]

Where do you guys mount your receivers ? as there's not much room in the "Dome"

 

[Bartman]

brendon,
i'm just heading out to try to drum up some business but will post pics when i get back. i zip-tied it to the frame alongside the electronics then put extenders under the dome to fit the receiver. pics will explain it better as soon as i get home.
bart

 

[Bartman]

here are a few pics of my jacked up cap, mounted receiver, and the extensions under the cap. i only use two nuts to hold the cap on since that's all i can easily access.
i have a piece of dense 1/4 foam padding under the receiver since it sits over a bunch of little bolt heads.

 

[brendonvz]

here are a few pics of my jacked up cap, mounted receiver, and the extensions under the cap. i only use two nuts to hold the cap on since that's all i can easily access.
i have a piece of dense 1/4 foam padding under the receiver since it sits over a bunch of little bolt heads.

Thanks for the pics... thats has certainly sprung some ideas
BTW the reciever powered up fine last night and all the lights started up ... I connected up a couple of spare servos and well ..... ITS ALIVE !
Thanks again.

 

[brendonvz]

First flight yesterday ... came down a little hard on the tiles broke the landing gear ... that is some flimsy landing gear for sure, it was only from about 5 foot and it snapped on the ski bracket , has anyone strengthened the landing gear up at all ? I'm thinking of wedging 4 sponge balls on the ends of the skis to absorb any knocks ... I'll post some pics later if I can get my hands on some today ...

 

[brendonvz]

Had a look round the net this morning and saw some other quads with what looked like polystyrene cistern floats as landing gear ... I might try that, as long as it has enough clearance for the battery and just until I can fly it well enough to put the camera on , and hey I could even land on water , now that would be daring !

 

[Bartman]

the gear are a problem point. they don't have much tolerance for botched landings so you've got to be careful to land straight down and very gently. putting anything on the tubes may just cause the tubes to flex and they'll snap too if they're allowed to bend too much.
i'm just curious, were you trying to skid it in to land with some forward motion like a helicopter in a hurry might do?

 

[brendonvz]

the gear are a problem point. they don't have much tolerance for botched landings so you've got to be careful to land straight down and very gently. putting anything on the tubes may just cause the tubes to flex and they'll snap too if they're allowed to bend too much.
i'm just curious, were you trying to skid it in to land with some forward motion like a helicopter in a hurry might do?

Came down slightly sideways, so kinda "bent the ankle" and it snapped (didn’t help I landed on tiles)
I think I'll try some sponge squares on the motors with an even height sponge in round the fuselage, so as to still get air to fan and of course make some sort of a battery hanger, or maybe move the battery to the top of the dome .. Ideas ideas ?

 

[Bartman]

why wouldn't you put the battery where it's supposed to go just above the camera mount on that little platform under the body? post some pics and we'll get you going again.

i posted this at RCGroups so here it is again

this may or may not help with the landing gear issues

for the new guys, when you are approaching to land try coming to the spot you want to land and holding the quad two or three feet above the ground. notice if it is drifting or not. if it is drifting at all, make control inputs that will hold the quad over one spot and get it stable. when it's stable, hold those controls and reduce the throttle just enough so it starts to go down very slowly. when it just touches the ground smoothly reduce the throttle the rest of the way. if it's going down too quickly you may have to bump the throttle a little to stop the descent just as it nears the ground then smoothly reduce it as it touches. the important thing is to hold the control inputs to keep it from drifting as it nears the ground. you shouldn't try to land the quad like a plane and let it run along the ground on the skids before stopping. get it close to the ground, keep it from drifting, then lower it slowly to the ground.

maybe that'll help?