Moderator Comment by Ken on January 10, 2010 at 6:27pm

Sweet. Google says 1,000 yen is $10.80 US. It looks like it is identical to a sensor they announced a year and a half ago, but with the addition of rate info. I can find lots of press, but no silicon for the predecessor. (The new one isn't out til March.) Is this vaporware? Hope not...

Planned Release
Sample price 1,000 yen (including tax)
Planned monthly production 1 million units (March 2010)
Development Mechatronics, Materials & Process (MMP) Division,
Nagaoka Plant (Nagaoka City, Niigata Prefecture)
Production Mechatronics, Materials & Process (MMP) Division,
Nagaoka Plant (Nagaoka City, Niigata Prefecture)

Specifications
Product name HSCD Series
Dimensions (W × D × H) 2.5mm × 2.5mm × 0.7mm
Magnetic field measurement range ±0.6mT
Output resolution 0.5μT / LSB
Operating temperature -20°C to +85°C
Supply voltage (analog) 2.5V type
Supply voltage (digital) 1.8V type
Average current consumption (when active) Max. 200 μA
Average current consumption (when on standby) Max. 5 μA

Moderator Comment by Jack Crossfire on January 10, 2010 at 8:26pm

Obviously intended for monocopters. Full attitude from magnetometers has been discussed already & busted.

Comment by Xander on January 11, 2010 at 1:39am

From what I've seen of magnetometers, I dont think you'd get steady enough readings for it to replace a gyro if it's anywhere near a motor. Neat idea though...

Comment by Martin Seven on January 11, 2010 at 5:13am

@Michael Zaffuto: A mag can drift as much as 60° if improperly shielded. Or if it's surrounded by strong EM emitters, like motors or RF gear. It's a serious issue especially on small multicopters, where the EMI density goes up to insane levels.

Comment by Mauro Brandan on January 11, 2010 at 10:56am

hopes for hobbyist purposes?

Comment by Edouard H on January 11, 2010 at 11:37am

I have done some testing on an EZstar with a PNI Micromag 3-axis mag. When putting the sensor in the nose, the engine perturbation is hardly noticeable. It is not very good for crashes, but it works. For Quadcopters, i agree it is probably a different story.

Comment by Matt on January 11, 2010 at 5:31pm

" there exists a method by which a 3-axis magnetometer and 3-axis accelerometer can be used to obtain full attitude that is not subject to centripetal acceleration errors."

That sounds promising. I wonder what the maximum update rate would be that you could get out of this sensor.
Combining it with an accelerometer and you have quite a small, cheap IMU module. The only remaining obstacle would be to minimise the effect of unwanted magnetic fields/ferromagnetic materials on the sensor. Perhaps a way to do this is by selecting motors and parts with a low interference potential and combine this with clever positioning of the sensor. Or use multiple sensors in locations around the airframe and average the result.
Most quadcopter designs use magnetometers very well for heading detection but is this because it is only interpolating into one axis(yaw)?

Comment by Edouard H on January 12, 2010 at 1:59am

For PNI Micromag, there is a trade-off between precision(gain) and update-rate. A good compromise seems to be with "Period select" set to 1024 which leads to 15 msec measurement time per axis => about 50 msec for a 3-axis measurement.

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