Very unusual problem encountered last week flying FPV with the Neo 2

[JustDavid]

Let me start with some background. I have Peripheral Neuropathy, and I have a Spinal Cord Stimulator Implant to help manage the pain. There are two leads that run inside my spinal column up to I think C4/C5. The implant sends an electrical signal to the major nerve trunks for my arms which overrides and blocks the pain signals. Works quite well and I have had this implant in for 9 years, the first one was in for 10 years. My pain level had been up, so I had increased the output of the stim to 8 millivolts, up from the normal 6 millivolts.

So, now to the point of this story. I fly FPV with the Motion Controller in my left hand because I am left handed and it is more 'normal' for me. I have done this several times, but that day was the first time I had any issues. I was prepping for flight and I was getting 'Interference in MC Location' errors in the Goggles. I had seen this before when the MC is sitting in my lap and I have my vape close, but my vape was on the table beside me. There was nothing electronic or electrical anywhere close to my left hand.
I put the controller in my right hand, no error. Back in my left hand, error returns. I finish the short flight using my right hand.

In contemplating this issue, I asked Gemini about it. It is possible that the stimulator at 8 millivolts was producing an electromagnetic field in my left arm which was strong enough to be interfering with the IMUs in the Motion Controller. My next 2 flights with the MC were error free, but I had also turned down my stimulator to my usual 6 millivolts.

I have been around electronics all my life and I know strange and spooky things can happen with electronics. That was a very bizarre, and interesting couple of days.

 

[GFields]

Sounds like you have identified the issue.

 

[NEO 317]

I wonder if a compass held above your arm would detect a slight anomaly in the reading if turned up to 8mv?

.

 

[JustDavid]

I don't have a magnetic compass to test that theory . . .

 

[RcHawks]

I’m also left handed. Living in a right handed world has forced me to use my right hand with so many different tasks because the instuments were designed for a right handed person. Even though the MC can be set for right or left hand movements for the operator it’s more natural for me to use my right hand for flight. It does make sense with what you're saying in hindsight about going beyond a certain level it causes an issue with interference. I’m glad the device provides some relief from pain. With practice perhaps you’ll be more comfortable using your MC with your right hand.

 

[JustDavid]

While I can fly with my right hand, it doesn't feel comfortable.

And I agree, the 10% of us learn to adapt. My mother went to my grade school and threatened to sue the school if they did not stop trying to force me to write right handed. This was in the mid/late 60's. I had one Uncle, and my first niece are both left handed.

 

[RcHawks]

I also had the same issue in grade school with teachers pressuring me to be right handed. I dislocated my thumb on my left hand in the 6th grade trying to catch a football. This force me to learn to write with my right hand for 6 weeks until I healed. Then back to being a lefty.

 

[Droning on and on...]

I'm also a lefty like you guys, and very dominantly so. Reminds of learning golf as a teen (very important to my Dad ), but using right-hand clubs. I hit that "wall" of progress where I just couldn't seem to get better, and had a nasty hook I couldn't get rid of despite lots of instruction and coaching.

Switched to LH clubs and the hook disappeared, and my game took off. As the rest of you lefties know, many other stories like this for us... Scissors, circular saws, hell, WRITING!

Back to the subject: It's certainly possible the spinal stimulator is the culprit. However, the EE in me is very skeptical. I doubt the 6 or 8mv potential is traveling all the way to your hand and producing any meaningful electromagnetic field. My understanding of how these devices work is the stimulation at the spinal cord site, blocking (overwhelming) the pain signal coming from the nerve keeping it from making it to the brain. This is also why you have some other neuropathic side effects like loss of touch sensation (different nerves) – they get blocked too.

I bring all this up to just keep the idea open that it may be something else, even flaky MC3 hardware. If you haven't, try calibrating the MC3 IMU using your left hand, and see if thar helps.

 

[JustDavid]

I'm also a lefty like you guys, and very dominantly so. Reminds of learning golf as a teen (very important to my Dad ), but using right-hand clubs. I hit that "wall" of progress where I just couldn't seem to get better, and had a nasty hook I couldn't get rid of despite lots of instruction and coaching.

Switched to LH clubs and the hook disappeared, and my game took off. As the rest of you lefties know, many other stories like this for us... Scissors, circular saws, hell, WRITING!

Back to the subject: It's certainly possible the spinal stimulator is the culprit. However, the EE in me is very skeptical. I doubt the 6 or 8mv potential is traveling all the way to your hand and producing any meaningful electromagnetic field. My understanding of how these devices work is the stimulation at the spinal cord site, blocking (overwhelming) the pain signal coming from the nerve keeping it from making it to the brain. This is also why you have some other neuropathic side effects like loss of touch sensation (different nerves) – they get blocked too.

I bring all this up to just keep the idea open that it may be something else, even flaky MC3 hardware. If you haven't, try calibrating the MC3 IMU using your left hand, and see if thar helps.

I thought the same myself. But I saw the results, at 8 mv, I had errors with the MC in my left, none in the right. And errors went away after turning back down to my normal 6mv. I have had one successful flight since with no errors. I agree, it makes absolutely no sense at all