About Me:
Born 1971, been doing FF and RC planes since the late 1970's. My hobbies pretty much are AutoCAD, R/C plane design and construction, electronics design and construction related to RC applications, especially autopilots for very small UAVs.
About
Hometown:
Gilbert Arizona
Activity Feed
"I see your points and concur. My AttoPilot (2007 Beta testing, sales 2008-2011) used the 8-core Propeller 32 bit IC. The IMU version 3.0 used 2 Propeller IC (16 cores). Focus was on fast optimized loops running on their own physical cores, with…"
"Hi, I'm still alive and breathing! Doing more work than ever on "Atto" stuff. I didn't intend the video on V4 for wide audience so I took it off the Vimeo sit this morning. The V4 proto is at level of board + 1 mile of wires and just recently etched…"
"Sorry for derailment - this is waay off topic for the airspeed sensor."
"More specifically, "yaw" body rate maps to the left/right accel axis, and "pitch" body rate maps to the up/down accel axis. You don't need to know attitude of the banking turn because we already know that in a 6 DOF IMU, the accel and gyro chips…"
"@GaryMortimer - shhhhh. NDAs are in effect!"
"Centripetal force, being a "false" force, depends on speed relative to the medium the vehicle is moving through and "pushing against" to generate the forces, with assumption that the vehicle is more or less tracking in that medium without too much…"
"... and at these more extreme speeds, you could just ignore "airspeed" because any typical wind is now a small fraction of the airspeed, and just use GPS ground speed divided by Cosine of pitch to get body-speed. Common civilian GPS report speed up…"
"The airspeed equation I use has a 7/2 power in it, and thus ram pressure builds rapidly with airspeed. So 7Kpa is not at all unreasonable for measuring airspeed in really fast RC planes or UAVs, for example powered by a turbine. My calcs (with…"
"The Diff P sensor pictured on top right of the Atto board (Freescale MP3V5004G) is describe as "Gauge" type. One port is the nipple as shown, the 2nd port is a vent hole on backside of the package. The 8 leads are structured so that the package…"
"@Bgatti "This is the AttoPilot choice - at 3.92 kPA it has ~10 times less range."
Yes - the "AttoPilot" choice is a choice that perfectly matches dynamic range of sensor with dynamic range of what is being sensed. Any higher sensor range is…"
Yes - the "AttoPilot" choice is a choice that perfectly matches dynamic range of sensor with dynamic range of what is being sensed. Any higher sensor range is…"
"The Atto picture posted above shows:
1) top left is altitude sensor (absolute, only 1 port)
2) top right is differential (one usable port shown, the other 'vented' port on bottom of package between component and the PCB surface."
1) top left is altitude sensor (absolute, only 1 port)
2) top right is differential (one usable port shown, the other 'vented' port on bottom of package between component and the PCB surface."
"Here is why I wrote that: 0-4kPa allows 0-300 km/h airspeed. Atto (not "Otto") V2/V3 control board uses a 16bit ADC with some smoothing and filtering algorithms. The resolution with a 4 kPa sensor and this ADC gives decent airspeed resolution (the…"
"Range is 0 - 37 kPa. This is approx 10x too large for normal airspeeds (0 to 300 km/h). I write this comment because the wide range probably means too low of a practical resolution. My Adobe reader is hosed, so I'm not able to open the spec sheet…"
"Atto gets around wind estimation with a trick I think is clever and has some other advantages, but no I absolutely didn't mean any sarcasm. I mean that if your crab angle is 45 degrees, then obviously the wind speed must be about equal to aircraft…"
"AttoPilot doesn't have a wind estimator. I am tickled to read about people doing this."
