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Alternative digital airspeed sensor

Measurement Specialties have introduced a new digital pressure transducer that matches or exceeds the specs of the 4525DO, while costing less than half the price ($25 vs $61 at single unit quantities). You can find product details and a datasheet here.

Would it possible to get an indication of interest, to see if it’s worth me throwing together a PCB to suit? With a Molex Clickmate connector and pitot tube, I imagine I could get the total airspeed sensor package down to around $30 USD or less at volume.

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That is a nice find. It looks like it works on 3.3v as well, which makes it work well if you have a 3.3 V I2C bus, which I think is the case for PixHawk and other STM32 based flight controllers I think the original PX4 I2C sensor had some issues since that sensor is meant to work on a 5V bus, which meant that the link is marginal unless you add a level converter.

I would be interested, due to better I2C compatibility. Re the connector, I have found the 1.25 pitch JST-GH connectors work well ( as used on the PixRacer)

Maybe also combine this with an I2C magnetometer on the same wires or provide a space on the pcb for one?

The addition of a magnetometer is a good idea, and should be simple to implement.

I put forward the idea of Clikmate connectors to match those found on Pixhawk 2.1. The JST-GH look similar, however I think the PixRacer is unlikely to be widely adopted for fixed wing application due to limited connectivity? It doesn’t make much a difference to me at this point, but I’d like to put out a reference design that’s going to best suit the community.

Actually, it turns out I got that wrong. The Pixhawk 2.1 is only using Clik-Mate connectors for power module connections. Everything else is using 1.25mm JST-GH, so that keeps it uniform across the different boards.

Yes, we have hardware coming soon! The delay here has been getting the sensors. The boards have been ready for months :slight_smile:
We will do an i2c and a CAN version of this sensor.

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Great to know! Thanks.

@proficnc Does it have a magnetometer on-board?

Yes it does…

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Sounds cool. Which magnetometer ?

And the important bit. What price?

TYVM for doing this guys. I’ve had terrible problems with airspeed sensors in the past, one that has lasted 7 months. Poor build quality seems to be a part of the issue. Do me a favor and put all components that could possibly be required to ensure proper and LASTING operation, even in Texas 114deg F heat. A magnetometer is a great idea for several reasons, but if you don’t include the level shifter it will be for not as the sensor will fail. I’m looking for as much reliability and robustness as possible. This design has the potential to be the standard for YEARS. Please make it a good one!

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I had similar idea, but with additions:

  • Use SPI to connect with pressure sensor
  • Use LPC11C24 for simple single-chip solution, unfortunately it has big TQFP-48 that take lot of space
  • Make printed housing that holds pitot tube and PCB, make complete module
  • Instead of silicone tubes make channels in housing and fill PCB bay with silicone sealant.
Servers by jDrones