Differential Pressure Sensors SDP3x for Drones

septembre 4, 2017 4:10

In many drone applications the airspeed is an important information for reliable and controlled take off, landing and flight. The airspeed is most effectively measured with a pitot tube and a differential pressure sensor. Recently, PX4 integrated the differential pressure sensors sdp3x into an airspeed sensor development kit for VTOL and fixed wing UAV applications, which is fully integrated with the open source autopilot.

The integration includes a full aerodynamic software compensation model for the sensor and pitot tube making it a plug and play solution.

differential pressure sensors sdp3x

The development kit is now available in our store.

Lorenz Meier, founder and chief architect at PX4-Pro, says about the SDP3x sensor:

« Most airspeed sensors require calibration before every flight to guarantee accuracy, and are not sensitive enough to produce reliable readings at low airspeeds. The fully calibrated and temperature-compensated SDP3x sensor solves these problems and offers unprecedented accuracy and resolution. The calibration-free setup enables instant launch of VTOL drones, dramatically increasing the user experience for end users. And high sensitivity at low airspeeds allows closed-loop control during the transition phase from hovering to forward flight, increasing the reliability and safety of VTOL drones. »

Original article can be found in Sensirion’s website.

Differential pressure sensors sdp3x and Mass Flow Sensors (SDP33)

The SDP3x sensor family is Sensirion’s series of small differential pressure sensors designed for high-volume applications where size is a key requirement. It builds on the next generation CMOSens® sensor chip that is at the heart of Sensirion’s new differential pressure and flow sensing platform.

The digital SDP3x sensor features fast measurement speed, excellent accuracy, and long-term stability and has no zero-point drift. Furthermore, it is reflow solderable and provides extended functionality, such as smart averaging, multiple temperature compensation modes, configurable I2C address, and interrupts.

The analog SDP3x sensors offer a calibrated and temperature compensated analog voltage output. The output signal is configurable: different measurement speeds, output curves, and temperature compensations can be selected, even dynamically during operation mode.

Component SDP33 features :

  • Smallest size (5 mm x 8 mm x 5 mm) currently available, opening up new dimension of integration and applications possibilities
  • Measurement range ±1500 Pa (±2 in. H2O)
  • Excellent accuracy and repeatability, even below 1 Pa
  • Maximum airspeed : 50m/s
  • No zero-offset, no drift
  • Calibrated and temperature compensated
  • Fast sampling time of 2 kHz at 16-bit resolution
  • Digital I2C and analog output versions
  • Reflow solderable, shipped in tape-and-reel for pick-and-place
  • Smart averaging algorithm and other digital and analog features

Board Features :

  • Black SLS Case
  • Dimensions : 3.2cm x 1.6cm x 1cm (L x W x H)
  • Weight : 12g (with case, Rubber tubing and Pitot tube)
  • Connector : JST-GH 4pins (dronecode connector)

Included :

  • Airspeed Sensor
  • 2 x Rubber tubing
  • Pitot Tube
  • JST-GH 4pins cable