# ESP32-Paxcounter
**Wifi & Bluetooth driven, LoRaWAN enabled, battery powered mini Paxcounter built on cheap ESP32 LoRa IoT boards**
Tutorial (in german language): https://www.heise.de/select/make/2019/1/1551099236518668
# Use case
Paxcounter is an [ESP32](https://www.espressif.com/en/products/socs/esp32) MCU based device for metering passenger flows in realtime. It counts how many mobile devices are around. This gives an estimation how many people are around. Paxcounter detects Wifi and Bluetooth signals in the air, focusing on mobile devices by evaluating their MAC adresses.
Intention of this project is to do this without intrusion in privacy: You don't need to track people owned devices, if you just want to count them. Therefore, Paxcounter does not persistenly store MAC adresses and does no kind of fingerprinting the scanned devices.
Data can either be be stored on a local SD-card, transferred to cloud using LoRaWAN network or MQTT over TCP/IP, or transmitted to a local host using serial (SPI) interface.
You can build this project battery powered using ESP32 deep sleep mode and reach long uptimes with a single 18650 Li-Ion cell.
# Hardware
**Supported ESP32 based boards**:
*LoRa & SPI*:
- Heltec: LoRa-32 v1 and v2
- TTGO: [Paxcounter-Board*](https://www.aliexpress.com/item/32915894264.html?spm=a2g0o.productlist.0.0.3d656325QrcfQc&algo_pvid=4a150199-63e7-4d21-bdb1-b48164537744&algo_exp_id=4a150199-63e7-4d21-bdb1-b48164537744-2&pdp_ext_f=%7B%22sku_id%22%3A%2212000023374441919%22%7D), T1*, T2*, T3*, T-Beam, T-Fox
- Pycom: LoPy, LoPy4, FiPy
- Radioshuttle.de: [ECO Power Board](https://www.radioshuttle.de/esp32-eco-power/esp32-eco-power-board/)
- WeMos: LoLin32 + [LoraNode32 shield](https://github.com/hallard/LoLin32-Lora),
LoLin32lite + [LoraNode32-Lite shield](https://github.com/hallard/LoLin32-Lite-Lora)
- Adafruit ESP32 Feather + LoRa Wing + OLED Wing, #IoT Octopus32 (Octopus + ESP32 Feather)
- M5Stack: [Basic Core IoT*](https://m5stack.com/collections/m5-core/products/basic-core-iot-development-kit) + [Lora Module RA-01H](https://m5stack.com/collections/m5-module/products/lora-module-868mhz), [Fire IoT*](https://m5stack.com/collections/m5-core/products/fire-iot-development-kit)
*) supports microSD-card
*SPI only*:
- Pyom: WiPy
- WeMos: LoLin32, LoLin32 Lite, WeMos D32, [Wemos32 Oled](https://www.instructables.com/id/ESP32-With-Integrated-OLED-WEMOSLolin-Getting-Star/)
- Crowdsupply: [TinyPICO](https://www.crowdsupply.com/unexpected-maker/tinypico)
- TTGO: [T-Display](https://www.aliexpress.com/item/33048962331.html)
- TTGO: [T-Wristband](https://www.aliexpress.com/item/4000527495064.html)
- Generic ESP32
Depending on board hardware following features are supported:
- LoRaWAN communication, supporting various payload formats (see enclosed .js converters)
- MQTT communication via TCP/IP and Ethernet interface (note: payload transmitted over MQTT will be base64 encoded)
- SPI serial communication to a local host
- LED (shows power & status)
- OLED Display (shows detailed status)
- RGB LED (shows colorized status)
- Button (short press: flip display page / long press: send alarm message)
- Battery voltage monitoring (analog read / AXP192 / IP5306)
- GPS (Generic serial NMEA, or Quectel L76 I2C)
- Environmental sensors (Bosch BMP180/BME280/BME680 I2C; SDS011 serial)
- Real Time Clock (Maxim DS3231 I2C)
- IF482 (serial) and DCF77 (gpio) time telegram generator
- Switch external power / battery
- LED Matrix display (similar to [this 64x16 model](https://www.instructables.com/id/64x16-RED-LED-Marquee/), can be ordered on [Aliexpress](https://www.aliexpress.com/item/P3-75-dot-matrix-led-module-3-75mm-high-clear-top1-for-text-display-304-60mm/32616683948.html))
- SD-card (see section SD-card here) for logging pax data
Target platform must be selected in `platformio.ini`.
Hardware dependent settings (pinout etc.) are stored in board files in /hal directory. If you want to use a ESP32 board which is not yet supported, use hal file generic.h and tailor pin mappings to your needs. Pull requests for new boards welcome.
Some 3D printable cases can be found (and, if wanted so, ordered) on Thingiverse, see
Heltec,
TTGOv2,
TTGOv2.1,
TTGO,
T-BEAM,
T-BEAM parts,
for example.
Power consumption was metered at around 450 - 1000mW, depending on board and user settings in paxcounter.conf.
By default bluetooth sniffing not installed (#define *BLECOUNTER* 0 in paxcounter.conf). Installing and enabling bluetooth costs 30% more power + 30% flash storage for the software stack. If you enable bluetooth be aware that this goes on expense of wifi sniffing results, because then wifi and bt stack must share the 2,4 GHz RF ressources of ESP32. If you need to sniff wifi and bt in parallel and need best possible results, use two boards - one for wifi only and one for bt only - and add counted results.
# Preparing
## Install Platformio
Install PlatformIO IDE for embedded development to make this project. Platformio integrates with your favorite IDE, choose eg. Visual Studio, Atom, Eclipse etc.
Compile time configuration is spread across several files. Before compiling the code, edit or create the following files:
## platformio.ini
Edit `platformio_orig.ini` and select desired hardware target in section boards. To add a new board, create an appropriate hardware abstraction layer file in hal subdirectory, and add a pointer to this file in sections board. Copy or rename to `platformio.ini` in the root directory of the project. Now start Platformio. Note: Platformio is looking for `platformio.ini` in the root directory and won't start if it does not find this file.
## paxcounter.conf
Edit `src/paxcounter_orig.conf` and tailor settings in this file according to your needs and use case. Please take care of the duty cycle regulations of the LoRaWAN network you're going to use. Copy or rename to `src/paxcounter.conf`.
If your device has a **real time clock** it can be updated bei either LoRaWAN network or GPS time, according to settings *TIME_SYNC_INTERVAL* and *TIME_SYNC_LORAWAN* in `paxcounter.conf`.
## src/lmic_config.h
Edit `src/lmic_config.h` and tailor settings in this file according to your country and device hardware. Please take care of national regulations when selecting the frequency band for LoRaWAN.
## src/loraconf.h
Create file `src/loraconf.h` using the template [src/loraconf_sample.h](https://github.com/cyberman54/ESP32-Paxcounter/blob/master/src/loraconf_sample.h) and adjust settings to use your personal values. To join the network and activate your paxcounter, you must configure either OTAA or ABP join method. You should use OTAA, whenever possible. To understand the differences of the two methods, [this article](https://www.thethingsnetwork.org/docs/devices/registration.html) may be useful.
To configure OTAA, leave `#define LORA_ABP` deactivated (commented). To use ABP, activate (uncomment) `#define LORA_ABP` in the file `src/loraconf.h`.
The file `src/loraconf_sample.h` contains more information about the values to provide.
## src/ota.conf
Create file `src/ota.conf` using the template [src/ota.sample.conf](https://github.com/cyberman54/ESP32-Paxcounter/blob/master/src/ota.sample.conf) and enter your WIFI network&key. These settings are used for downloading updates via WiFi, either from a remote https server, or locally via WebUI. If you want to use a remote server, you need a PAX.express repository. Enter your PAX.express credentials in ota.conf. If you don't need wireless firmware updates just rename ota.sample.conf to ota.conf.
# Building
Use PlatformIO with your preferred IDE for development and building this code. Make sure you have latest PlatformIO version.
# Uploading
- **by cable, via USB/UART interface:**
To upload the code via cable to your ESP32 board this needs to be switched from run to bootloader mode. Boards with USB bridge like Heltec and TTGO usually have an onboard logic which allows soft switching by the upload tool. In PlatformIO this happenes automatically.
The LoPy/LoPy4/FiPy board needs to be set manually. See these instructions how to do it. Don't forget to press on board reset button after switching between run and bootloader mode.
The original Pycom firmware is not needed, so there is no need to update it before flashing Paxcounter. Just flash the compiled paxcounter binary (.elf file) on your LoPy/LoPy4/FiPy. If you later want to go back to the Pycom firmware, download the firmware from Pycom and flash it over.
- **over the air (OTA), download via WiFi:**
After the ESP32 board is initially flashed and has joined a LoRaWAN network, the firmware can update itself by OTA. This process is kicked off by sending a remote control command (see below) via LoRaWAN to the board. The board then tries to connect via WiFi to a cloud service (PAX.express), checks for update, and if available downloads the binary and reboots with it. If something goes wrong during this process, the board reboots back to the current version. Prerequisites for OTA are: 1. You own a PAX.express repository, 2. you pushed the update binary to your PAX.express repository, 3. internet access via encrypted (WPA2) WiFi is present at the board's site, 4. WiFi credentials were set in ota.conf and initially flashed to the board. Step 2 runs automated, just enter the credentials in ota.conf and set `upload_protocol = custom` in platformio.ini. Then press build and lean back watching platformio doing build and upload.
- **over the air (OTA), upload via WiFi:**
If option *BOOTMENU* is defined in `paxcounter.conf`, the ESP32 board will try to connect to a known WiFi access point each time cold starting (after a power cycle or a reset), using the WiFi credentials given in `ota.conf`. Once connected to the WiFi it will fire up a simple webserver, providing a bootstrap menu waiting for a user interaction (pressing "START" button in menu). This process will time out after *BOOTDELAY* seconds, ensuring booting the device to runmode. Once a user interaction in bootstrap menu was detected, the timeout will be extended to *BOOTTIMEOUT* seconds. During this time a firmware upload can be performed manually by user, e.g. using a smartphone in tethering mode providing the firmware upload file.
# Legal note
**Depending on your country's laws it may be illegal to sniff wireless networks for MAC addresses. Please check and respect your country's laws before using this code!**
(e.g. US citizens may want to check [Section 18 U.S. Code § 2511](https://www.law.cornell.edu/uscode/text/18/2511) and [discussion](https://github.com/schollz/howmanypeoplearearound/issues/4) on this)
(e.g. UK citizens may want to check [Data Protection Act 1998](https://ico.org.uk/media/1560691/wi-fi-location-analytics-guidance.pdf) and [GDPR 2018](https://ico.org.uk/for-organisations/guide-to-the-general-data-protection-regulation-gdpr/key-definitions/))
(e.g. Citizens in the the Netherlands and EU may want to read [this article](https://www.ivir.nl/publicaties/download/PrivacyInformatie_2016_6.pdf) and [this article](https://autoriteitpersoonsgegevens.nl/nl/nieuws/europese-privacytoezichthouders-publiceren-opinie-eprivacyverordening)) and [this decision](https://edpb.europa.eu/news/national-news/2021/dutch-dpa-fines-municipality-wi-fi-tracking_en)
(e.g. Citizens in Germany may want to read [this article of Wissenschaftliche Dienste des Deutschen Bundestages](https://www.bundestag.de/resource/blob/538890/3dfae197d2c930693aa16d1619204f58/WD-3-206-17-pdf-data.pdf)
Note: If you use this software you do this at your own risk. That means that you alone - not the authors of this software - are responsible for the legal compliance of an application using this or build from this software and/or usage of a device created using this software. You should take special care and get prior legal advice if you plan metering passengers in public areas and/or publish data drawn from doing so.
# Privacy disclosure
Paxcounter generates identifiers for sniffed Wifi or Bluetooth MAC adresses and and collects them temporary in the device's RAM for a configurable scan cycle time (default 60 seconds). After each scan cycle the collected identifiers are cleared. Identifiers are generated by using the last 2 bytes of universal MAC adresses. Personal MAC adresses remain untouched and are not evaluated. Identifiers and MAC adresses are never transferred to the LoRaWAN network. No persistent storing of MAC adresses, identifiers or timestamps and no other kind of analytics than counting are implemented in this code. Wireless networks are not touched by this code, but MAC adresses from wireless devices as well within as not within wireless networks, regardless if encrypted or unencrypted, are sniffed and processed by this code.
# LED blink pattern
**Mono color LED:**
- Single Flash (50ms): seen a new Wifi or BLE device
- Quick blink (20ms on each 1/5 second): joining LoRaWAN network in progress or pending
- Small blink (10ms on each 1/2 second): LoRaWAN data transmit in progress or pending
- Long blink (200ms on each 2 seconds): LoRaWAN stack error
**RGB LED:**
- Green: seen a new Wifi device
- Magenta: seen a new BLE device
- Yellow: joining LoRaWAN network in progress or pending
- Pink: LORAWAN MAC transmit in progress
- Blue: LoRaWAN data transmit in progress or pending
- Red: LoRaWAN stack error
# Display
If you're using a device with OLED display, or if you add such one to the I2C bus, the device shows live data on the display. You can flip display pages showing
- recent count of pax
- histogram
- GPS data
- BME sensor data
- time of day
- blank page
by pressing the button of the device.
# Sensors and Peripherals
You can add up to 3 user defined sensors. Insert your sensor's payload scheme in [*sensor.cpp*](src/sensor.cpp). Bosch BMP180 / BME280 / BME680 environment sensors are supported, to activate configure BME in board's hal file before build. Furthermore, SDS011, RTC DS3231, generic serial NMEA GPS, I2C LoPy GPS are supported, and to be configured in board's hal file. See [*generic.h*](src/hal/generic.h) for all options and for proper configuration of BME280/BME680.
Output of user sensor data can be switched by user remote control command 0x14 sent to Port 2.
Output of sensor and peripheral data is internally switched by a bitmask register. Default mask can be tailored by editing *cfg.payloadmask* initialization value in [*configmanager.cpp*](src/configmanager.cpp) following this scheme:
| Bit | Sensordata | Default
| --- | ------------- | -------
| 0 | Paxcounter | on
| 1 | unused | off
| 2 | BME280/680 | on
| 3 | GPS* | on
| 4 | User sensor 1 | on
| 5 | User sensor 2 | on
| 6 | User sensor 3 | on
| 7 | Batterylevel | off
*) GPS data can also be combined with paxcounter payload on port 1, *#define GPSPORT 1* in paxcounter.conf to enable
# Power saving mode
Paxcounter supports a battery friendly power saving mode. In this mode the device enters deep sleep, after all data is polled from all sensors and the dataset is completeley sent through all user configured channels (LORAWAN / SPI / MQTT). Set *#define SLEEPCYCLE* in paxcounter.conf to enable power saving mode and to specify the duration of a sleep cycle. Power consumption in deep sleep mode depends on your hardware, i.e. if on board peripherals can be switched off or set to a chip specific sleep mode either by MCU or by power management unit (PMU) as found on TTGO T-BEAM v1.0/V1.1. See *power.cpp* for power management, and *reset.cpp* for sleep and wakeup logic.
# Time sync
Paxcounter can keep a time-of-day synced with external or on board time sources. Set *#define TIME_SYNC_INTERVAL* in paxcounter.conf to enable time sync. Supported external time sources are GPS, LORAWAN network time and LORAWAN application timeserver time. Supported on board time sources are the RTC of ESP32 and a DS3231 RTC chip, both are kept sycned as fallback time sources. Time accuracy depends on board's time base which generates the pulse per second. Supported are GPS PPS, SQW output of RTC, and internal ESP32 hardware timer. Time base is selected by #defines in the board's hal file, see example in [**generic.h**](src/hal/generic.h). Bonus: If your LORAWAN network does not support network time, you can run a Node-Red timeserver application using the enclosed [**Timeserver code**](/src/Node-RED/Timeserver.json). Configure the MQTT nodes in Node-Red for the LORAWAN application used by your paxocunter device. Time can also be set without precision liability, by simple remote command, see section remote control.
# Wall clock controller
Paxcounter can be used to sync a wall clock which has a DCF77 or IF482 time telegram input. Set *#define HAS_IF482* or *#define HAS_DCF77* in board's hal file to setup clock controller. Use case of this function is to integrate paxcounter and clock. Accurary of the synthetic DCF77 signal depends on accuracy of on board's time base, see above.
# Mobile PaxCounter using openSenseMap
This describes how to set up a mobile PaxCounter:
Follow all steps so far for preparing the device, selecting the packed payload format. In `paxcounter.conf` set PAYLOAD_OPENSENSEBOX to 1. Register a new sensebox on https://opensensemap.org/. In the sensor configuration select "TheThingsNetwork" and set decoding profile to "LoRa serialization". Enter your TTN Application and Device ID. Setup decoding option using `[{"decoder":"latLng"},{"decoder":"uint16",sensor_id":"yoursensorid"}]`
# SD-card
Data can be stored on an SD-card if the board has SD-card slot. To enable this feature, specify the board's SD interface and it's pins in the board's hal file (src/hal/