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The Mechanics of Motion Sensing
Dr. Eggman writes, "The AP has a short technology piece on the mechanics that go into the motion-sensing capabilities of the Wii and PS3 controllers. It also details some of the past uses of the technology and gives a nice overview of just how far the technology has come from the earliest missile-guidance sensor equipment."
They're so minute and move so little you will never have to worry about them breaking. Because they are so tiny you can never build up appreciable inertia in them. They are functionally considered solid state devices and they should last pretty much forever.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
http://www.freescale.com/files/sensors/doc/data_sh eet/MMA7260Q.pdf
A good picture of a two-axis accelerometer can be seen here: http://users.wpi.edu/~cfurlong/me-593Mech.html (second picture down). Sensing is usually performed by capacitive combs, structures which act as capacitors, with their capacitance varying with displacement.
MEMS accelerometers have dropped in price in recent years because there's a big market: the automotive sector. A typical new car needs two accelerometers, one for the traction control system measuring roughly plus-or-minus 2 to 4g, and one for airbag deployment measuring more like 50g.
Two big manufacturers are Analog Devices and ST Microelectronics, though others exist.
The high demand of the automotive sector has driven prices right down; sensors which would have cost hundreds of dollars in the past can now be purchased in bulk for less than $4. In fact, you could order one right now; component retailers will sell you one for less than $15.
"Goodness me, how unlike the FBI to abuse the trust of the American public." -- The Onion
oops! http://www.freescale.com/webapp/sps/site/prod_summ ary.jsp?code=MMA7260QT
There are some app notes below.
"Silicon spring" is misleading because it implies there are moving parts within the accelerometer that can break. In actuality, the proof mass is held perfectly still using a feedback loop to cancel the externally applied force. The magnitude of this applied force is read out as the acceleration. No calibration is ever needed thanks to the feedback loop.
Right from the source: http://www.st.com/stonline/products/literature/ds/ 11115.pdf
These things are not exactly new. They are used in the automotive sector, or for "stabilizers" in camcorders.
The sooner you fall behind, the more time you have to catch up.
It is not held perfectly still in both piezoresistive and capacitive accelerometers. You need to have displacements to measure the acceleration, and stiction is the problem solved with feedback/force units.
Or maybe I just misunderstood you..
It has accelerometers AND the sensor thing. Tennis actually just uses the accelerometers, it works quite well no matter where you're facing.
Username taken, please choose another one.
Tilt sensors indirectly measure orientation (tilt). They look at the change in the gravitational acceleration vector with respect to the sensor coordinate frame.
Most accelerometers can survive 3000G or so.
Engineering is the art of compromise.
No the OP was right. It is also true of accelerometers. And the fact that they are measuring data during a dog fight it irrelevant, it is the amount of time/distance they are measuring data. They include a random walk error that is small for a short time/distance, but compounds over time.
You will find that typically this is corrected with something that can give an absolute position (eg GPS). Your absolute positioning device typically also has a know error. The values from both of these are generally married using a Kalman Filter or Extented Kalmna Filter.
I've written code to do this in the past.
I suggest that you also do some. 4 years of Mechatronic Engineering would be good start.
meh