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Old Nov 18, 2009, 09:15 AM
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Quadcopters: Be Safe!!

Hi All -

I just wanted to share an experience I had last night so nobody else has to make the same mistake.

Last night I finally got my quad put together (custom build) and put on my APC 10x4.7 props. I went to calibrate the ESCs and completely underestimated the thrust of this thing. Fortunately I was able to maintain a hold of the quad but it sliced me pretty bad on my right pinky finger. Fortunately my brother was right there and reacted quickly and unplugged the battery from the quad (my xbee link came unlinked so the motors were just spinning full throttle). Blood was spewing everywhere and My girlfriend rushed me to the emergency room, where I received stitches on my finger. There were 4 deep slices.

I was so excited to have completed my build that I overlooked some safety measures. I got very lucky, too - if the quad would have gotten a hold of my face or other body parts, I could have sustained some serious injuries...

Lesson: These things are POWERFUL! Please, be very, very careful...

-Jamie

PS I have pictures of the whole incident but they are sort of bloody so I decided not to post them.
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Old Nov 19, 2009, 07:18 AM
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It's funny how threads like this never get any replies, even though the advice in them is very important.
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Old Nov 19, 2009, 11:56 AM
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Perhaps readers were too traumatised by your accident to post replies?

Anyway, do take care. By the way, what motors are you using?
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Old Nov 19, 2009, 12:09 PM
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I read your post and took it all in. I too have had an encounter w/ a quad blade. Mine was however was a comparison to a paper cut. Enough to make me learn though.

To be honest when I first read your post, my first thoughts were.. POST THE BLOODY PICS But then again probably a good decision on your part NOT to. We don't need anyone fainting in front of their computers.

Play safe,

Carl
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Old Nov 19, 2009, 12:25 PM
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Originally Posted by altronpower View Post
Perhaps readers were too traumatised by your accident to post replies?

Anyway, do take care. By the way, what motors are you using?
I am using KDA 20-22L motors:
http://www.hobbycity.com/hobbycity/s...idProduct=4700

They have some serious power!
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Old Nov 19, 2009, 12:26 PM
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Originally Posted by ReaLyze View Post
I read your post and took it all in. I too have had an encounter w/ a quad blade. Mine was however was a comparison to a paper cut. Enough to make me learn though.

To be honest when I first read your post, my first thoughts were.. POST THE BLOODY PICS But then again probably a good decision on your part NOT to. We don't need anyone fainting in front of their computers.

Play safe,

Carl
Yes, you were lucky

And yes, probably best not to post the pics. There was a LOT of blood!
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Old Nov 20, 2009, 12:16 AM
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Quote:
Originally Posted by asifjahmed View Post
I just wanted to share an experience I had last night so nobody else has to make the same mistake...
Ouch! Sounds like a scene from a future SAW movie. I'm using these same motors and props on mine. Kind of like having a flying blender I suppose.

Sounds like you may have hit an artery. I'm glad you didn't post the bloody picts
Can you still work a TX? If not, I prescribe months of physical therapy for you in front of an RC simulator

Seriously hope it starts feeling better soon and thanks for posting the warning.
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Old Nov 20, 2009, 06:48 PM
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For every kg RTF weight about 1000W power...... Yep. These are not toys.
Lucky it was just your pinky finger.

Of course you now have a checklist which requires you to step back a safe distance from the kopter before turning on the motors, a power switch on the flight controler (not the ESCs and batteries; they pull too much power, but as long as they shut down when the FC is without power, that's OK), and that failsafe program as top priority on your programming list (turn off motors if signals is lost while near the ground).....
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Old Nov 20, 2009, 07:15 PM
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Hi all,
Just for the record. I am currently nursing a 3" gash in my arm with 5 stitches in it. This was the result of an oversight brought about by complacency and excitement. I was in the process of tuning my quad and very excited (and happy) to have my quad hovering in my back yard. I have some video which I will post later. I had flattened 3 batteries this day and was getting very confident with my piloting skills as a result. I flattened my fourth charge and picked up the quad to go back to the workshop but forgot to disarm the ESCs. While I was walking I accidentally brushed the throttle on the TX and the beast launched into a full throttle attempt to get away from me, which it did but not before cutting up my arm in a few places. This also required a trip to emergency and a few embarrassing retelling of the story.
I felt such an idiot!! But I can assure you all I will not be remiss with safety again.
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Old Nov 20, 2009, 09:33 PM
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i kinda want to see pics..... glad you are mainly OK
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Old Nov 21, 2009, 02:05 AM
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Originally Posted by don_cocinero View Post
Hi all,
Just for the record. I am currently nursing a 3" gash in my arm with 5 stitches in it. This was the result of an oversight brought ..... picked up the quad to go back to the workshop but forgot to disarm the ESCs. While I was walking I accidentally brushed the throttle on the TX and the beast launched into a full throttle attempt to get away from me, which it did but not before cutting up my arm in a few places. ...
If you're talking about the throttle stick type of disarming, you may not have forgotten. I once accidentally tipped over my TX while grabbing for it after setting up the APMk and turning on the on/off switch. It managed to do the arm ESCs throttle stick movement and then go to just over hover throttle. So I-m looking at a APMk suddenly flying at about 1 meter and gradually ascending and drifting away from me with a slight yaw, and a TX lying upside down.

Even without stitches that convinced me to change my sequence slightly to not switching the mechanical on/off switch to on until I am ready to fly with the TX already firmly in hand and more or less standing, and always turning that switch OFF before picking up the APMk after any flight or testing.
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Old Nov 21, 2009, 02:20 AM
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Originally Posted by don_cocinero View Post
Hi all,
Just for the record. I am currently nursing a 3" gash in my arm with 5 stitches in it...
Oh no That is terrible

Which quad tried to have you for lunch? It may be good to figure out which quads try to eat people more often so we can determine which one has the best arming/disarming procedure.

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Originally Posted by sxk122 View Post
i kinda want to see pics..... glad you are mainly OK
Same here but I'm not sure for the same reasons Direct posts are a little grusom but links to images that we can choose to click on may help the safety idea stick more for some people after seeing some of the bad aftermath. Not sure what the forum rules on posting links to gory images is though. I imagine it's probably not allowed, and for good reason
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Old Nov 22, 2009, 07:01 PM
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Originally Posted by Arthur P. View Post
If you're talking about the throttle stick type of disarming, you may not have forgotten. I once accidentally tipped over my TX while grabbing for it after setting up the APMk and turning on the on/off switch. It managed to do the arm ESCs throttle stick movement and then go to just over hover throttle. So I-m looking at a APMk suddenly flying at about 1 meter and gradually ascending and drifting away from me with a slight yaw, and a TX lying upside down.

Even without stitches that convinced me to change my sequence slightly to not switching the mechanical on/off switch to on until I am ready to fly with the TX already firmly in hand and more or less standing, and always turning that switch OFF before picking up the APMk after any flight or testing.
Hi Arthur,
Yes, it is the throttle stick type arm/disarm. What got me with this trap for those with vigilance blurred by excitement () was the fact that the props were not spinning. I am not posing this as a valid reason for me to blame the Quad please understand this. You see, I am running both a Mikrocopter and a Quadpowered board. So it was a silly case of forgetting which board I was testing momentarily. While both boards use a throttle stick arm/disarm system, the Mikro board spins the prop until it is disarmed but the Quadpowered board does not.
At the end of it all....I should have been more alert Yesterday The rags were removed, the stitches came out and I now have a new scar. All that's left now is the record of a valuable lesson painfully learned.
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Old Nov 22, 2009, 07:19 PM
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Originally Posted by RCvertt View Post
Oh no That is terrible

Which quad tried to have you for lunch? It may be good to figure out which quads try to eat people more often so we can determine which one has the best arming/disarming procedure.

Same here but I'm not sure for the same reasons Direct posts are a little grusom but links to images that we can choose to click on may help the safety idea stick more for some people after seeing some of the bad aftermath. Not sure what the forum rules on posting links to gory images is though. I imagine it's probably not allowed, and for good reason
Hi RCvertt,
Always a joy to hear from you.
It was the QuadPowered Quad that tried to julienne my arm. In my opinion, the Mikro approach to arm/disarm is safer because of the visual component to the process. I hasten to add though that this incident does not point to any particular Quad as more dangerous but instead has highlighted the need to observe strict safety procedure at all times and it will certainly not deter me from continuing to use the Quadpowered board. After all it is a great board and the responsibility for safety is mine from the outset.
I have nonetheless added more cautions to the safety section of the Quadpowered user Guide along with more references to safety procedure interspersed throughout the guide. We all know that these machines are not toys. Depending on the motors you are using you will be interacting with a combined output of 1Hp or more, so there is no room for complacency here. Mia culpa
As far as pics are concerned, I think the time to take photos is immediately after the accident so that the graphic impact of the moment is fully maximised. But of course I was too busy trying to prevent my supply of blood from coating the patio at the time and my wife was too busy looking horrified. Now that the stitches are out, even I look at it and wander what all the fuss was about. Funny how it all just fades into the tapestry of life.

Cheers
Don
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Old Nov 23, 2009, 04:18 AM
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Originally Posted by don_cocinero View Post
...In my opinion, the Mikro approach to arm/disarm is safer because of the visual component to the process...
Interesting. I wouldn't have thought about that but now that you mention it I do use the configurator quite often to confirm it's disarmed when I'm up close and working on the quad. I don't think we are making any quads look worse then others. A visual indication is a simple but great idea. I wouldn't mind having a little red light go on my quad to let me know it's armed when I'm not using the configurator. Even just having the green light on my quad continually blink when it's armed and solid when it's disarmed, or something like that, would help a lot. All boards could impliment this rather easily. Thanks for the info.

Quote:
Originally Posted by don_cocinero View Post
...But of course I was too busy trying to prevent my supply of blood from coating the patio at the time and my wife was too busy looking horrified.
Ok. I guess I can forgive you guys this time

I'm glad you took care of the situation instead of reaching for the camera. Too many people reach for the camera these days when something goes wrong instead of helping.
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