Getting Started - DeeEmm/DIY-Flow-Bench GitHub Wiki
The Following guide will walk you through what is required to get the DIYFB system up and running on your bench. Currently we support both MAF based benches and Differential (orifice) style benches.
The system comprises of three distinct aspects:
- The MCU / Shield
- The physical hardware
- The software
The MCU / shield
The recommended MCU is the Wemos D1 R32. The DIYFB shield is designed to work with this specific MCU.
Any ESP32 based MCU will run the DIYFB software, and any 'UNO' sized ESP32 board will be pin compatible with the DIYFB shield. You should be able to edit the pin configuration file (pins.json) to make your board work with the ESP32 shield.
The shield itself is a DIY self-solder shield designed to be easy to build, and utilises readily available components.
If you are a novice we recommend sticking with the recommended Wemos D1 board and official DIYFB shield and recommended component selection. It is however possible to substitute components and MCUs with the appropriate corresponding code changes, as well as designing your own PCB or breadboard design.
More detailed information on the shield can be found in the 'Shield Design' section
Physical Hardware
There are many ways to build the physical bench, but all flow benches consist of the same basic configuration: A vacuum source, A measuring or metering section and the test surface.
The most simple MAF based bench consists of a shop vac for a vacuum source, and a length of 80/90/100mm tube to mount the MAF in with a suitable test surface at the end. More complex DIY flow bench designs are available, for example the PTS differential style bench plans are widely recognised and comparable with other industry standard products.
The design of the bench is entirely at the users choice, but it should be considered that the performance of the vacuum source will have a direct impact on the ability of your bench. The DIYFB code will work as a 'floating depression' style bench for simple systems but the ability to test at a fixed depression at an industry standard level should not be overlooked.
Currently the firmware supports both MAF based benches and Differential (orifice) style benches.
More detailed information on Bench design can be found in the 'Bench Design' section
The DIYFB Firmware.
The DIYFB firmware is designed to be run on the ESP32 platform This means that it should run an any ESP32 device. The official default recommended device is the Wemos ESP32 D1. Clone versions of these are inexpensive and readily available. The Wemos D1 is an UNO sized ESP32 breakout board that is pin compatible with the official FIYFB shield. The DIYFB Firmware is preconfigured to run on the WEMOS ESP32 D1 without any configuration changes.
For the initial installation, firmware can be uploaded to the ESP32 using a firmware loader. Once the initial firmware has been uploaded, further firmware updates can be made via the GUI.
Additional configuration is then carried out via the configuration page in the GUI.
More detailed information on configuration and setup can be found in the Firmware section.
Official firmware releases are available via the Releases page and via the Master branch
The current development code is available in the DEV branch. Please note that whilst the DEV branch may contain additional functionality and features that are not yet published into the Master branch. DEV code is not yet validated and may contain errors and / or performance issues.
For a production system we always recommend using the current official release.
Getting the right components
If you want to build your own shield, selection of the components you use to build your bench is the most important aspect of ensuring that your build goes smoothly, or in some cases even works at all. Not all MAF sensors are made equal and not all MAF sensors have published flow characteristic data that you can use to set up your MAF sensor within the code.
Similarly the same applies to pressure sensors as well. Pressure sensor choice will have a direct impact on system accuracy and stability.
In both cases you need to select sensors with a range that suits the flow characteristics of the items that you want to test. It's no use choosing an Audi RS4 MAF that flows 860cfm, if you are only going to be testing go-kart engines.
Web UI
The DIYFB system is designed to be used from a tablet or WiFi enabled device with a web browser. It should work with all modern smartphones, tablets and computers. Google Chrome is the recommended browser.
When building your flow bench it is worth considering purchasing a cheap tablet that can be used as the interface. This is the original design intent.
Advanced API communications
An API interface is available via the serial communications interface. This allows access to all menu functions via Serial communications. For example; the Arduino serial monitor. All menu commands are available to the API. Additionally there are various diagnostic commands available to the API that are not available to the regular WebUI.
The system can easily be used via the serial monitor to send command and receive data.
For a full listing of all API commands, please refer to the API section
There is also a HTTP based API. However this still needs some work to bring it up to a usable level.
The HTTP API is designed to be used by third party devices via the ethernet network and provides for bench controls and data to be accessed remotely. For example this could be used by a device such as a RaspberryPi for data logging, or from a remote PC connection to import data directly into Excel.