Hi everyone,
Has anyone ever had any issues with interfacing the SF02 Lidar with Pixhawk 3.3V A/D port ?
I got 3 Lightware SF02s, 2 Pixhawks and only one SF02 works has described in http://ardupilot.org/copter/docs/common-rangefinder-sf02.html . The 2 other SF02 have to be powered with a BEC and connected to +5V and GND screw terminals to make them working properly. I'm running ArduCopter 3.3
Thanks,
René
Replies
Hi Rene,
If you haven't already done so, download the SFO2 manual from LightWare here;
http://www.lightware.co.za/shop/en/drone-altimeters/7-sf02f.html
I would recommend that you take a look at the Pixhawk + 5 power when you have hooked up the SF02 as shown in the doc link.
Does the same physical Pixhawk work with all 3 SFO2 without a UBEC or is it 3 different Pixhawks?
If one Pixhawk setup works without a UBEC on all 3 SFO2s then it is probable that the +5 is being pulled lower by other circuits on those systems (looking at the +5 buss should show this by being below 5 volts.
If the same Pixhawk works on one and not the other two SFO2s then it is possible that you are already low on 5 volts and one of the SFO2's is just not quite as sensitive as the others.
It is necessary that the Pixhawk have a solid +5 volts.
Running servos or other things directly from the Pixhawk can certainly pull the power down and is not recommended without supplying additional power beyond the Pixhawk Power Module as described in the Wiki documentation.
The SFO2 only draws 150 milliamps, so if it is the sole extra load it should not be pulling the supply down.
Basically you need to look at the 5 volts with a voltmeter and you need to determine whether it is the various Pixhawks or the various SFO2s that are the root of the problem.
Best Regards,
Gary