Information
Table Of Contents
- A. Overview
- 1. Getting started
- 1.1 The BME688 Gas Sensor
- 1.2 Example: Coffee vs. Normal Air
- 1.3 A Few Things To Keep In Mind
- 1.4 Step 1: Record Normal Air
- 1.5 Step 2: Record Espresso Coffee
- 1.6 Step 3: Record Normal Air Again
- 1.7 Step 4: Record Filter Coffee
- 1.8 Step 5: Import & Label The Data
- 1.9 Step 6: Create New Algorithm and Classes
- 1.10 Step 7: Train And Evaluate The Algorithm
- 1.11 Step 8: Export The Algorithm
- 1.12 Conclusion
- 2. Introduction
- 2.1 What is it about? – An analogy
- 2.2 Why the BME688?
- 2.3 What is a use case for a gas sensor?
- 2.4 What is special about the BME688 gas sensor?
- 2.5 How can I evaluate BME688 performance for a specific use case?
- 2.6 How can I use the results for my product development?
- 3. Glossary
- 3.1 Sensor Board
- 3.2 Measurement Session
- 3.3 Algorithm
- B. Process Steps
- 1. Configure Board
- 1.1 Overview
- 1.2 Board Type
- 1.3 Board Mode
- 1.4 Heater Profile
- 1.5 Duty Cycle
- 1.6 Board Layout
- 2. Record Data
- 2.1 Overview
- 2.2 Start recording
- 2.3 During recording
- 2.4 End recording
- 3. Import Data
- 3.1 Overview
- 3.2 Data Overview
- 3.3 Board ID
- 3.4 Board Type
- 3.5 Board Mode
- 3.6 Session Name
- 3.7 Session Date
- 3.8 Specimen Data
- 4. Collect Specimens
- 4.1 Overview
- 4.2 Label
- 4.3 Comment
- 4.4 Session
- 4.5 Start & End Time
- 4.6 Duration
- 4.7 Cycles Total
- 4.8 Cycles Dropped
- 4.9 Remaining Cycles
- 4.10 Board Configuration
- 4.11 Board ID
- 4.12 Board Type
- 4.13 Board Mode
- 4.14 Show Configuration
- 5. Train Algorithms
- 5.1 Overview
- 5.2 Name
- 5.3 Created
- 5.4 Classes
- 5.5 Class Name & Color
- 5.6 Common Data
- 5.7 Data Balance
- 5.8 Data Channels
- 5.9 Neural Net
- 5.10 Training Method
- 5.11 Max. Training Rounds
- 5.12 Data Splitting
- 6. Evaluate Algorithms
- 6.1 Overview
- 6.2 Confusion Matrix
- 6.3 Accuracy
- 6.4 Macro-averaged F1 Score
- 6.5 Macro-averaged False Positive Rate
- 6.6 Training Data
- 6.7 Test Data
- 6.8 Additional Testing
- 2.1
Bosch Sensortec | BME AI-Studio Documentation 6 | 49
Modifications reserved | Data subject to change
without notice Document number: BST-BME688-AN001-00
1.3 A Few Things To Keep In Mind
See: "1:26 - A Few Things To Keep In Mind"
Before we start with the measurements, there are three things to keep in mind:
If you have a brand new BME board, you should stabilize the sensors on the board before taking any
measurements. To do so, connect the board to power with a micro USB cable and let it run for at least 24 hours.
This procedure is necessary only once and your board is then ready to take reliable measurements.
Make sure that your BME board is configured correctly. New BME boards come already preconfigured with a
standard setting – so if you have a brand new board, you do not have to worry about the configuration for now.
Make sure that an SD card is inserted in the board.
1.4 Step 1: Record Normal Air
See: "2:08 - Step 1: Record Normal Air"
Let us start the measurement session for our coffee detection example.
Let us record normal air as our first specimen. We are just going to record the gas composition of the room. Additional
smells to make the detection more robust should be added later. However, to keep it simple in this example we just stick
to normal air for now.
Connect the BME board to power and place the board on your table. Always be careful not to touch the sensors with
your fingers while handling the board.
If everything is OK and the board is recording data, the red LED is flashing every two seconds. Let the board record for
about 30 minutes.
1.5 Step 2: Record Espresso Coffee
See: "2:48 - Step 2: Record Espresso Coffee"
Now, let us move on to the coffee. For this example, we prepared two types of coffee in order to have a bit of variance
in our measurements: espresso and filter coffee. Let us measure the espresso coffee first.
Place the espresso coffee in a relatively airtight container. Press “Button 1” (labeled “S1”) on the board to mark this
moment in the data. Place the board in the container together with the coffee, and record the gas composition for 30
minutes.
1.6 Step 3: Record Normal Air Again
See: "3:19 - Step 3: Record Normal Air Again"
After that, let us measure normal air again. Take the board out of the container. This time, press “Button 2” (labeled “S2”)
on the board to set another mark in the data.
Place the board again on your table, and record the gas composition for another 30 minutes. Put the container with the
coffee far away, so it does not interfere with the recording.