Probably a bug in BME688/BSEC 2.0 with 4 classes

[Danj]

We tried to use all 4 classes in the BME AI-Studio:
Class A: Air
Class B: Coffee
Class C: Tea
Class D : Flower
Then in our application with BSEC Library we got for Air:
BSEC_OUTPUT_GAS_ESTIMATE_1=0.00
BSEC_OUTPUT_GAS_ESTIMATE_2=0.99
BSEC_OUTPUT_GAS_ESTIMATE_3=0.00
BSEC_OUTPUT_GAS_ESTIMATE_4=0.00
for Coffee the same:
BSEC_OUTPUT_GAS_ESTIMATE_1=0.00
BSEC_OUTPUT_GAS_ESTIMATE_2=0.99
BSEC_OUTPUT_GAS_ESTIMATE_3=0.00
BSEC_OUTPUT_GAS_ESTIMATE_4=0.00
It looks like BSEC_OUTPUT_GAS_ESTIMATE_1 doesn't change at all.

If we remove classes C and D from the algorithm, we get for Air:
BSEC_OUTPUT_GAS_ESTIMATE_1=0.99
BSEC_OUTPUT_GAS_ESTIMATE_2=0.00
and for Coffee:
BSEC_OUTPUT_GAS_ESTIMATE_1=0.00
BSEC_OUTPUT_GAS_ESTIMATE_2=0.99
this is correct.

BME AI Studio: 1.6.0
BME68x: 4.4.6
BSEC: 2.0.6.1

[MightyNate]

I'm afraid I can't help you with your question, but I wonder how you managed to retrieve the values for BSEC_OUTPUT_GAS_ESTIMATE_X.
Whatever sample rate I use to subscribe the BSEC_OUTPUT_GAS_ESTIMATE_X the bsec_update_subscription function returns an error.
That's why I wonder if I really need to subscribe them explicitly or whether it is enough to pass the config that I received from AI Studio to the bsec_set_configuration function?

If I get the BSEC_OUTPUT_GAS_ESTIMATE_X to work I will try to replicate the bug for comparison.

[Danj]

1. Sample rate must be BSEC_SAMPLE_RATE_HIGH_PERFORMANCE
2. Need to subscribe to all BSEC_OUTPUT_GAS_ESTIMATE_X (BSEC_OUTPUT_GAS_ESTIMATE_1,BSEC_OUTPUT_GAS_ESTIMATE_2,BSEC_OUTPUT_GAS_ESTIMATE_3,BSEC_OUTPUT_GAS_ESTIMATE_4). Even if you only use 2 classes.
You can see the logic of use in the example for BCEC 2.0.

[BSTRobin · Accepted solution]

Hello Danj,

Has you correctly labeled the gas? Maybe you can make the data collection time longer for each different kind of gas and have a try.
You shall make sure that the air is the fresh air without other smell.
Coffee for training and coffee for field test shall be the same concentration.

[BSTRobin]

Hello Danj,

Could you give further feedback?