Barometer Issues

Navio / Edge Hardware
1

Hi, I’ve encountered some Barometer issues

If i run the Python or C++ example, it seems to be read ‘random’ values.

Once powered by USB:

pi@navio-rpi /opt/src/Navio/C++/Examples/Barometer $ sudo ./Barometer
Failed to read device(-1): Input/output error
Temperature©: 37.385159 Pressure(millibar): 969.417236
Temperature©: -532.174377 Pressure(millibar): -2477.178467
Temperature©: -267.773163 Pressure(millibar): -442.001068
Temperature©: -107.103722 Pressure(millibar): 536.828918
Temperature©: -34.879921 Pressure(millibar): 856.569458
Temperature©: 10.914048 Pressure(millibar): 935.492249
Temperature©: 28.299593 Pressure(millibar): 975.826538
Temperature©: 37.845177 Pressure(millibar): -1058.129395
Temperature©: 23.703375 Pressure(millibar): -1029.307617
Temperature©: 38.148769 Pressure(millibar): -767.760864
Temperature©: 38.156048 Pressure(millibar): -109.741173
Temperature©: 38.165775 Pressure(millibar): 369.003357
Temperature©: 38.179008 Pressure(millibar): 578.783142
Temperature©: 38.148304 Pressure(millibar): 947.352112
Temperature©: -532.174377 Pressure(millibar): -2477.784180
Temperature©: -532.174377 Pressure(millibar): -2476.995117
Temperature©: -500.578278 Pressure(millibar): -2217.255859
Temperature©: -256.742737 Pressure(millibar): -366.013000
Temperature©: -107.465889 Pressure(millibar): 552.729248
Temperature©: -32.446495 Pressure(millibar): 835.202637
Temperature©: 23.997505 Pressure(millibar): 965.590698
Temperature©: 33.601387 Pressure(millibar): 987.958618
Temperature©: 35.316860 Pressure(millibar): -1052.976440
Temperature©: 9.288847 Pressure(millibar): -1000.039795
Temperature©: 38.224205 Pressure(millibar): -562.157104
Temperature©: 38.205013 Pressure(millibar): -74.185623
Temperature©: 38.200912 Pressure(millibar): 343.133759
Temperature©: 38.213680 Pressure(millibar): 784.144470
Temperature©: 38.206207 Pressure(millibar): 944.163879
Temperature©: 38.221622 Pressure(millibar): 1006.430298
Temperature©: -532.174377 Pressure(millibar): -2476.702637
Temperature©: -346.333435 Pressure(millibar): -1008.203613
Temperature©: -197.056976 Pressure(millibar): 31.665390
Temperature©: -62.683964 Pressure(millibar): 758.680786
Temperature©: -10.437016 Pressure(millibar): 887.257568
Temperature©: 20.528704 Pressure(millibar): 957.517334
Temperature©: 32.776104 Pressure(millibar): 985.943054
Temperature©: 35.015385 Pressure(millibar): -1052.362061
Temperature©: 20.846060 Pressure(millibar): -1023.484314
Temperature©: 38.270920 Pressure(millibar): -770.584717
Temperature©: 38.249878 Pressure(millibar): -305.971008
Temperature©: 38.262184 Pressure(millibar): 378.497040
Temperature©: 38.266289 Pressure(millibar): 677.893372
Temperature©: 38.280251 Pressure(millibar): 897.811035
Temperature©: -532.174377 Pressure(millibar): -2522.287842
Temperature©: -532.174377 Pressure(millibar): -2476.644531
Temperature©: -287.587097 Pressure(millibar): -580.763245
Temperature©: -122.883430 Pressure(millibar): 456.219452
Temperature©: -47.708389 Pressure(millibar): 788.018433
Temperature©: 5.964398 Pressure(millibar): 958.096924
Temperature©: 29.569208 Pressure(millibar): 978.432495
Temperature©: 38.799625 Pressure(millibar): -1060.074585
Temperature©: 29.650400 Pressure(millibar): -1041.427979
Temperature©: 4.639282 Pressure(millibar): -990.672058
Temperature©: 38.294144 Pressure(millibar): -302.045868
Temperature©: 38.300236 Pressure(millibar): 251.764145
Temperature©: 38.313667 Pressure(millibar): 579.175842
Temperature©: 38.319950 Pressure(millibar): 877.822876
Temperature©: -532.174377 Pressure(millibar): -2517.187012
Temperature©: -532.174377 Pressure(millibar): -2476.423340
Temperature©: -415.722748 Pressure(millibar): -1538.396729
Temperature©: -244.504211 Pressure(millibar): -282.886871
Temperature©: -92.305130 Pressure(millibar): 607.445618
Temperature©: -40.402786 Pressure(millibar): 841.018677
Temperature©: 13.484530 Pressure(millibar): 941.066223
Temperature©: 30.867413 Pressure(millibar): 981.309082
Temperature©: 38.937855 Pressure(millibar): -1060.356201
Temperature©: 27.538628 Pressure(millibar): -1037.124023
Temperature©: 38.339806 Pressure(millibar): -700.022461
Temperature©: 38.351513 Pressure(millibar): -123.534454
Temperature©: 38.353832 Pressure(millibar): 435.270538
Temperature©: 38.361244 Pressure(millibar): 770.265137
Temperature©: -532.174377 Pressure(millibar): -2526.429199
Temperature©: -532.174377 Pressure(millibar): -2476.232422
Temperature©: -263.986938 Pressure(millibar): -415.747375
Temperature©: -112.761093 Pressure(millibar): 508.223450
Temperature©: -35.712276 Pressure(millibar): 825.575562
Temperature©: 0.826348 Pressure(millibar): 946.372742
Temperature©: 27.951599 Pressure(millibar): 974.453308
Failed to read device(-1): Input/output error
Temperature©: 38.398102 Pressure(millibar): 1029.057495
Temperature©: 23.243555 Pressure(millibar): -1028.370605
Temperature©: 38.398300 Pressure(millibar): -771.421143
Temperature©: 38.371433 Pressure(millibar): -261.746887
Temperature©: 38.385921 Pressure(millibar): 282.010620
Temperature©: 38.394131 Pressure(millibar): 601.599060
Temperature©: 38.399025 Pressure(millibar): 878.810303
Temperature©: -532.174377 Pressure(millibar): -2502.920898
Temperature©: -532.174377 Pressure(millibar): -2476.090820
Temperature©: -423.792511 Pressure(millibar): -1601.363525
Temperature©: -199.727234 Pressure(millibar): 9.370508
Temperature©: -68.685577 Pressure(millibar): 709.873291
Temperature©: -12.452148 Pressure(millibar): 915.680237
Temperature©: 24.879492 Pressure(millibar): 967.215576
Temperature©: 38.309296 Pressure(millibar): -1059.075195
Temperature©: 23.903608 Pressure(millibar): -1029.715820

and another time powered by a 4S battery

pi@navio-rpi /opt/src/Navio/C++/Examples/Barometer $ sudo ./Barometer
Temperature©: 39.342159 Pressure(millibar): -875.197266
Temperature©: 39.307617 Pressure(millibar): -156.762894
Temperature©: 39.298485 Pressure(millibar): 388.230469
Temperature©: 39.320648 Pressure(millibar): 622.305786
Temperature©: 39.323830 Pressure(millibar): 931.716309
Temperature©: -532.174377 Pressure(millibar): -2482.022949
Temperature©: -532.174377 Pressure(millibar): -2472.262695
Temperature©: -370.579620 Pressure(millibar): -1210.862183
Temperature©: -119.129845 Pressure(millibar): 493.748840
Temperature©: -42.431591 Pressure(millibar): 803.280334
Temperature©: 11.310713 Pressure(millibar): 933.820801
Temperature©: 33.696476 Pressure(millibar): 985.521118
Temperature©: 39.107121 Pressure(millibar): -1060.701294
Temperature©: 9.956215 Pressure(millibar): -1001.387085
Temperature©: 39.395294 Pressure(millibar): -666.494812
Temperature©: 39.391254 Pressure(millibar): -149.518509
Temperature©: 39.378483 Pressure(millibar): 367.473663
Temperature©: 39.360485 Pressure(millibar): 630.795227
Temperature©: 39.386688 Pressure(millibar): 898.622559
Temperature©: -532.174377 Pressure(millibar): -2448.174561
Temperature©: -532.174377 Pressure(millibar): -2472.115234
Temperature©: -451.721710 Pressure(millibar): -1819.593628
Temperature©: -227.246796 Pressure(millibar): -168.056305
Temperature©: -84.266541 Pressure(millibar): 642.221191
Temperature©: -24.541651 Pressure(millibar): 892.804443
Temperature©: 18.629314 Pressure(millibar): 950.528137
Temperature©: 29.170595 Pressure(millibar): 974.963928
Temperature©: 38.660267 Pressure(millibar): -1059.790527
Temperature©: 25.451670 Pressure(millibar): -1032.870728

I’m not sure if it is related, but i had an shocking experience with one of my flights where my quad would not come back to the ground it was flying up and up and up, even throttle to down-most position did nothing, i just managed to bring it down again by switching to Acro mode and coming down with a swoop

Within the flight, my barometer was not covered, but those numbers coming from my desk :confused:

Any help is appreciated.

2

Isn’t APM running when you are launching baro example?

3

I see, if i start two examples, the values are still ok, why are the values going crazy if i run apm ?

4

APM is occupying the i2c bus and if you launch the example simultaneously you will see rubbish data due to collisions.

Your flight issue is most likely related to the uncovered baro.

5

I thought the same it is related to the uncovered barometer, I’ve cut some foam and will give it another try, hopefully it works now.

6

I tried it again with foam but had the same issue !

Just to be sure, I’ve used ‘Altitude Hold’ Flight Mode and i did not attached a GPS antenna, I’ve disabled all GPS related Failsafe checks, so i guess it should be fine to fly without the GPS antenna, or I’m wrong ?

How would you test if it works without another fly away ?

7

The foam you linked will most certainly not work.
It is closed cell foam which lets no air through.
What you need is open cell foam. It is often used in packaging (jewelry, watches, electronic parts etc.) or on microphone heads. If you can breath through it, it is the right type.
With your foam, you are completly blocking pressure changes from the baro. That might be even worse than an uncovered baro.

8

I’m curious why EMLID is not providing a small piece of foam with the navio board if it is necessary. I’ve tried to breath through it and it ‘works’ i feel a small resistance. I have some other foam with a different density.

IMG_20160104_144646~2.jpg2799×2098 1.06 MB

Probably this one is better ?

9

This looks like the right type.

10

Ok i will give it another try with the “new” foam !

Do you have any hint how i can prevent another fly away ? Can i use some kind of cord or rope probably one on top and one at the bottom ^^

I repaired my mini quad now 3 times without any ‘real’ fly experience, which is really awkward :neutral_face:

11

Why didn´t you switch back to stabilize mode as soon as the althold mode failed? If the copter does not fly right in stabilize mode, there is no use in trying any other mode.
It should be possible to bring the copter down unharmed in stabilize mode, even if it is almost out of sight.

12

good point, I’ve used acro mode to bring it down but I’ve forgot to try stabilize, next time i will give it a try first, probably i save some bucks :smile:

13

Always use Stabilize as your primary/default flight mode with APM. There were times when Acro did not even work properly.