Wow...if that last sentence is true, it's an amazing oversight on the part of the manufacturer. All of the controllers would potentially have this problem. And most of them -- at least the ones not sold to a mechanical engineer -- would have to be replaced.
Most of the inexpensive choppers are contra-rotating, they have two main rotors that spin in opposite directions, and are really stable and easy to control. Changing the speed of the two rotors makes the bird yaw, rotor speed controls lift, and there's a conventional swash plate for pitch, which is the only servo needed.
re: "It appears the monkeys were out to lunch during any design verification phase granting approval of the controller assembly process."
Maybe there was a common PCB level defect (e.g., missing solder mask) and certainly an absense of post assembly electrical test. Were the wires properly stripped and clean, promoting adequate solder flow instead of the bridging associated with dewetting? And where were the in-process and final inspection QA chimps?
Design verification isn't the answer for sloppy manufacturing, defective parts, lack of functional testing and apparent absense of Quality Inspection -- all too often issues in low-end consumer electronics.
I wouldn't pick on the monkeys while the entire zoo remains suspect.
I wonder if anything produced was ever checked as a finished product. If samples were tested fully, a repeated defect would be noticed. If this was just a one off defect, then you would be lucky to find it. Replacement would just be a cost of doing business. If this was on all the boards, then it would be found eventually if someone tested samples. And hopefully all the defective ones found and held before they were shipped.
I agree it may not be a bad design, and I expect the manufacturing may be capable. It may just be an assumption that everything made must be good, so why ever check?.... Or it may just be a single mistake and they were lucky a Sherlock was there with an impressive fix.
I agree, this is likely a unit that was missed in lot sample testing/inspection. Even six-sigma quality programs yield defects, albeit if statistically few. This particular escapee landed in the right hands for remedy. Think of those odds.
I'm aware that most of the cheaper units have two rotors. The reason I asked the question is because the author says he bought a more expensive one this year, and I wondered if it has anything in common with the robotic quadrotors that keep cropping up in so many robot R&D projects.
The author stated that he bought a "more expensive" model for his son for Christmas. This does not necessarily mean that it was engineered & produced w/ MERCEDES BENZ quality in force. The overwhelming bulk of toys manufactured today are "Made in China", and I suspect that this helicopter may also be in that group.
Commentors discussing SIX SIGMA, etc. should recall that China is having continued difficulty with "ONE ALPHA", so they have a long row to hoe to get to SIX SIGMA, given the Greek alphabet.
Our granndaughter got a sewing machine for Christmas from the other grandparents. It was Made in China, and even though she is a mindful young lady, it failed soon after she received it. Some of the plastic parts of the machine did not align properly, the foot was ineffective, and the needle broke because it did not engage correctly. And, so it is now in a landfill somewhere in the county. We will buy her a used SINGER when we see a good deal so she can continue to advance her interest in sewing.
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