Wish List - Hardware - Atmospheric - Revision history

PTT: rewrite with more information

2007-08-14T21:56:54Z

rewrite with more information

Johan: Variometer Page - transcluded from wishlist

2007-07-22T20:20:22Z

Variometer Page - transcluded from wishlist

Johan: Vario /* Hardware */

2007-07-22T19:13:45Z

Vario - ‎Hardware

Johan at 17:45, 22 July 2007

2007-07-22T17:45:26Z

Johan: Framework for a Variometer Design

2007-07-21T18:36:22Z

Framework for a Variometer Design

Speedevil: clarify - gyroscopes can't be used as compass.

2007-07-20T12:50:47Z

clarify - gyroscopes can't be used as compass.

Glenn: +{{Hardware Wishlist}}

2007-07-17T06:53:21Z

+{{Hardware Wishlist}}

Glenn: catspec

2007-07-16T11:37:33Z

catspec

Glenn: +cat

2007-07-16T10:13:14Z

+cat

Speedevil: paste

2007-04-21T09:09:01Z

paste

New page

*Add a Digital Barometer, Compass (make use of the gyroscope hardware suggested elsewhere) and Elevation Meter, as well as an integrated link to online weather services would make for a fine fully functional world thermometer and weather forecaster. Visual Interface could be very nice if show as an old fashion meter next to an alpha numeric display of info. --[[User:Jamie K|Jamie K]] 15:04, 17 April 2007 (CEST)

The variometer signal is simply the derivative of the barometer signal. It gives a much more accurate vertical speed signal than is possible with GPS. It would probably be best to filter and differentiate the analog pressure signal and then digitize. This kind of measurement is used by the flee flying community (hanggliding, paragliding, ballooning). A device that allows teams of pilots to share position and speed (with accurate vertical speed) data would be lots of fun.
[http://en.wikipedia.org/wiki/Variometer Variometer Reference]

@@ Line 1: / Line 1: @@
 {{Hardware Wishlist}}
-*Add a Digital Barometer, Compass and Elevation Meter, as well as an integrated link to online weather services would make for a fine fully functional world thermometer and weather forecaster. Visual Interface could be very nice if show as an old fashion meter next to an alpha numeric display of info.
+Add a digital barometer (pressure sensor), which could also be used as altimeter (height sensor), thermometer and hygrometer (humidity sensor).
+Both are quite small and have a low power usage. The pressure sensor has more uses than the humidity sensor, and has a real I2C interface instead of the not fully I2C compatible interface of the SHT1x, so should be given more priority. (IMHO [[User:PTT|PTT]] 23:56, 14 August 2007 (CEST))
-{{:Variometer}}

@@ Line 4: / Line 4: @@
-====Hardware====
+{{:Variometer}}
-−
-References to applicable transducers:
-*[http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPX4100 Freescale MPX4100 (was Motorola)]
-−
-====Signal Conditioning====
-−
-The absolute pressure signal needs to be:
-#Differentiated
-#Filtered
-−
-*Operational amplifiers in the following configuration:
-−
-====A/D====
-We would need two A/D channels:
-#Absolute Pressure - 12 bit minimum (calc needed)
-#Differential Pressure - 10 bit minimum (calc needed)
-−
-====Driver Code====
-The driver code samples the input channels and converts the input values from pressure to altitude:
-−
-The relationship between static pressure and pressure altitude is defined in terms of the properties of the International Standard Atmosphere. Up to 36,090 ft this can be expressed as:
-−
-<math>
-z =\left (1-\left(\frac{P_{ind}}{101.325}\right)^{0.190263} \right ) \times \frac{87.828}{0.00198122}
-</math>
-−
-Where:
-−
-*z = pressure altitude (meter)
-*<math>P_{ind}</math> = static pressure (kPa)
-−
-These values are provided to listeners in multiple applications.
-The sample rate should be application adjustable to conserve power.
-−
-====Application code====
-Applications can use the altitude data or combine the data with GPS and accelerometer data.
-Commonly Kalman filter/observer techniques are used to combine data from multiple sensor types into a high accuracy low noise estimate of position and speed in 3 axis. (ref needed)
-−
-=====Variometer Code=====
-Combine measurements as described above.
-Apply knowledge about the aircraft dynamics to increase accuracy:
-*Total Energy compensation
-*Relative Netto Compensation - use accelerometer data to sense when glider is turning in a thermal
-−
-'''User Interface'''
-−
-*Display speed data in ergonomic manner.
-*Display speed for pilots in group.
-*Visual and audible guidance to pilot with best climb rate (given reasonable proximity)

@@ Line 11: / Line 11: @@
 References to applicable transducers:
-*[http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPX5010 Freescale MPX5010 (was Motorola)]
+*[http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPX4100 Freescale MPX4100 (was Motorola)]
 ====Signal Conditioning====

@@ Line 27: / Line 27: @@
 ====Driver Code====
-The driver code samples the input channels and converts the input values from pressure to altitude.
+The driver code samples the input channels and converts the input values from pressure to altitude:
 These values are provided to listeners in multiple applications.
 The sample rate should be application adjustable to conserve power.

← Older revision		Revision as of 11:37, 16 July 2007
Line 4:		Line 4:
	[http://en.wikipedia.org/wiki/Variometer Variometer Reference]		[http://en.wikipedia.org/wiki/Variometer Variometer Reference]

−	[[Category:Hardware]]	+	[[Category:Hardware ideas]]

@@ Line 2: / Line 2: @@
 *Add a Digital Barometer, Compass and Elevation Meter, as well as an integrated link to online weather services would make for a fine fully functional world thermometer and weather forecaster. Visual Interface could be very nice if show as an old fashion meter next to an alpha numeric display of info.
 The variometer signal is simply the derivative of the barometer signal. It gives a much more accurate vertical speed signal than is possible with GPS. It would probably be best to filter and differentiate the analog pressure signal and then digitize. This kind of measurement is used by the flee flying community (hanggliding, paragliding, ballooning). A device that allows teams of pilots to share position and speed (with accurate vertical speed) data would be lots of fun.
 [http://en.wikipedia.org/wiki/Variometer Variometer Reference]

← Older revision		Revision as of 10:13, 16 July 2007
Line 3:		Line 3:
	The variometer signal is simply the derivative of the barometer signal. It gives a much more accurate vertical speed signal than is possible with GPS. It would probably be best to filter and differentiate the analog pressure signal and then digitize. This kind of measurement is used by the flee flying community (hanggliding, paragliding, ballooning). A device that allows teams of pilots to share position and speed (with accurate vertical speed) data would be lots of fun.		The variometer signal is simply the derivative of the barometer signal. It gives a much more accurate vertical speed signal than is possible with GPS. It would probably be best to filter and differentiate the analog pressure signal and then digitize. This kind of measurement is used by the flee flying community (hanggliding, paragliding, ballooning). A device that allows teams of pilots to share position and speed (with accurate vertical speed) data would be lots of fun.
	[http://en.wikipedia.org/wiki/Variometer Variometer Reference]		[http://en.wikipedia.org/wiki/Variometer Variometer Reference]
		+
		+	[[Category:Hardware]]