Is there anyone working on using the wii nunchuck and motion+ as an IMU for a plane? I see that the nunchuck to arduino code exists, and I've seen that the arduino DCM code exists. I haven't, however, seen a wii-based IMU for a plane. Is there some reason for this? Is it:A. The gyros/accelerometers are inadequate or unsuitable for this applicationB. The I2C interface is too slow or limiting in some wayC. Too new--nobody has gotten around to it yetD. Too darn big (you could take the PCB's out of the controllers, but they'd still be much bigger than an UAVdeboard or ardupilot)E. all of the above.?As far as price goes, it seems like you couldn't beat it. At $40 for the IMU, it's cheaper than an FMA pilot assist. I'd love to move this forward, but I'm curious why it hasn't already been done. Any thoughts?
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Thanks for the replies. So, it sounds like the I2C port is slow, and the modest cost savings don't compensate for the loss of flexibility, refinement, additional size, etc. compared to a dedicated IMU. That sound about right?
I have multiple nunchucks at home and an arduino, so for me, the price to play is only $20 for the motion+, and $3 for a breakout board for the connector (provided I don't destroy the nunchuck!). I suspect there are a lot of people in the same boat. It may not be suitable for an airplane, but I'd like to give it a try in an autonomous monster truck. Thanks for the input.
Part of the game is having something accessible to everyone & not a hack. People have hacked $20 IMUs forever, but to have something popular it has to include standard Arduino chips, standard gyros, & easy interfaces. It has to do what everyone wants in addition to what your personal project wants & that's going to drive it to the $100 range.
I've been playing with Motion+/Numcuck as a way of understanding how accelerometers/gyros work in the real world. I've placed the motion+ board inside the numchuck (which gives a nice thing to hold/wave around) and connected it to PC via the I2C on the video port.
That said I don't think that it's a realistic option for the drone, simple because the boards are big, update rate is pretty slow (I2C bit clock 400KHz max and you need to read/write around 20 bytes each sample) and they really aren't that cheap - even if very accessible (ie. every big store).
The cost for the active bits on the ArduIMU is around $20 for gyros, $6 for accelerometers and $5 for the micro, plus the cost of board, glue logic and regulators. Having it all built/programmed/tested for you at $100 seems pretty good to me.
With the motion+/numchuck for $40 you still have to have a processor and some code (I'm still trying to understand how I might code a DCM in python)....
Mungewell.
Hi Nathan, the standard Wiimote only contains a triple axis accelerometer (MMA7260Q) and no gyros. I am not sure on the motion+. Checkout the link from sparkfun showing its internals.
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I have multiple nunchucks at home and an arduino, so for me, the price to play is only $20 for the motion+, and $3 for a breakout board for the connector (provided I don't destroy the nunchuck!). I suspect there are a lot of people in the same boat. It may not be suitable for an airplane, but I'd like to give it a try in an autonomous monster truck. Thanks for the input.
That said I don't think that it's a realistic option for the drone, simple because the boards are big, update rate is pretty slow (I2C bit clock 400KHz max and you need to read/write around 20 bytes each sample) and they really aren't that cheap - even if very accessible (ie. every big store).
The cost for the active bits on the ArduIMU is around $20 for gyros, $6 for accelerometers and $5 for the micro, plus the cost of board, glue logic and regulators. Having it all built/programmed/tested for you at $100 seems pretty good to me.
With the motion+/numchuck for $40 you still have to have a processor and some code (I'm still trying to understand how I might code a DCM in python)....
Mungewell.
http://voidbot.net/nunchchuk-and-wii-motion-plus-6-DOF.html
Perhaps the common notion is that it's just not a complete IMU? Thanks.