Most of the toy class of helicoptors that I have seen are controlled with a smart phone, which is NOT what I am looking for. Regular radio control will be better because while a toy helicopter may cost $75, a smartphone costs a lot more than that, way to much to risk breaking as a toy controller.
I collect inexpensive RC helicopters, design and build custom machinery for a living, and am pretty amazed at what is being delivered for the price. For $130 and up there are a lot of decent 4 axis machines being offered by Esky and E-flight. In the lowest price range, there are two channel - basically two motors with speed control which provide pitch (actually lift) and yaw - and are trimmed by shifting the CG for slightly forward flight - but require a line of sight infared signal from the transmitter to control. Then the 3 channel which add a propeller to lift up or press down the tail boom (for pitch) and a radio tranmitter. I suspect the company that made this low end model did not have the budget to inspect every unit going off their line...
I would also assume that they were all made that way. Unfortuntaley, most people won't be able to fix theirs like you did. So long gone are the days where you buy something and expect it to actually work.
Two counter rotating rotors each with its own motor. Pitch is controlled by a third motor and small propeller mounted on the end of the tail. To pitch "forward", the propeller lifts the tail, and to pitch "backward", the propeller pushes the tail down.
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.
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.
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 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.
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.
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