RoadTest: STWIN SensorTile Wireless Node Dev Kit
Author: meera_hussien
Creation date:
Evaluation Type: Development Boards & Tools
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: The other parts which I think comparable to this product is the STEVAL-MKSBOX1V1
What were the biggest problems encountered?: There is no big problem encountered while testing this product. The material provided was sufficient and easy to understand. Moreover, the material provided was very well explained.
Detailed Review:
By Hussien
STWIN Sensor Tile is a development kit and a reference design that simplifies the prototyping and testing of advanced industrial IoT applications such as condition monitoring and predictive maintenance. The advantage of this kit is that, it comes with a range of embedded industrial-grade sensors and an ultra-low-power microcontroller for vibration analysis of 9-DoF motion-sensing data across a wide range of vibration frequencies, including very high frequencies audio and ultrasound spectra, high precision local temperature and environmental monitoring. Below are the features of the kit.
The kit supports two types of connectivity which are BLE wireless connectivity and Wi-Fi connectivity. The BLE is available through an on-board module, meanwhile, for the Wi-Fi connectivity, a special plugin expansion board is required.
The figure above shows the STWIN core system block diagram. From the figure above it can be seen the type of sensor available and how it is connected to the microcontroller. It also shows the whole picture of how each element are connected to the core system. Below is the functional block diagram of sensing elements and STM32L4R9ZIJ6.
Let's look at the core system board sensor locations
That's about the location of the sensor placed on the STWIN board. For more details on the board, can be referred at https://www.st.com/en/evaluation-tools/steval-stwinkt1.html#resource
The image below is the STWIN top and bottom picture and the last image is the protective plastic case.
That's the basic introduction for STWIN. For more details and documentation, it can be obtained from the ST official site. I have shared the link in the above.
In the first part of this roadtest, we shall see the unboxing of the kit. The kits is well packaged. Below is the image of the package and the unboxing
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And the video below is the unboxing video of the kit.
Once finished unboxing the kit, next is to power up the kit. But before that, the plastic case needs to be fixed with the board to avoid any short circuit while working on it. The video below shows how to install the plastic case with the board. When installing the board to the plastic case, the battery needs to be installed together because of the connection for the battery is located at the bottom side of the battery. The battery can be left connected to the board without any worries. This is because the power circuits will automatically decide on which power source to use. If we are powering it up with the battery alone, then it will run on the battery. But when we power the board via USB, the board will run on the USB power and at the same time recharge the battery. the power circuits block diagram illustrates how it works.
Now let's watch the plastic case and battery installation videos.
Once the installation of the plastic case is done we are almost ready to power the board for the first time. But before that, the other baord which comes together with the STWIN which is the STLINK-V3MINI board does not have a proper protection or casing. Without a proper enclosure the board will be prone for short circuit. Going through the official site, i came across a 3d print design file. Within the file, it is the enclosure design for the STLINK-V3MINI . Below is the image of the design.
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The 3D print model was 3d printed. The image and video below shows the 3D printed model and how to fix the STLINK-V3MINI inside the printed enclosure.
| Header 1 | Header 2 |
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And below is the video
Once all these are done, we are ready to power the board for the first time.
The board can be powered up by three-way, the first is using the battery and the second option is by USB and the last is using an external power supply. In our case, we will first power it up using the USB. Running the board for the first time does not require any software setup yet. We will look into the software requirement in the next section. As for now, we will just look into powering up the board and run it with the preinstalled software. In order to get this software we need to install the ST BLE Sensor from the google play store.
Once the installation of the app is completed, we are ready to test our first run. The video below shows how it is done.
The data observed in the STBLE Sensor app can be monitor in computer via the serial communication. In order to view this, we can use either the PUTTY or Term Tera software. In this review, I have chosen Tera Term software. After plugging the USB cable to the STWIN open the Tera Term. If the board is detected automatically, it will show as the figure below
In my case the port is COM9. Once the connection is successful, we will see the details of the board as shown in the figure below
And once the STWIN board is connected to the smartphone, the data can be seen in the terminal window as shown in the figure below
A closer look at the figure above
From the figure above we can see the data which is being sent via Bluetooth to the smartphone. Another way to view the STWIN data is by using the serial data log. This can be done as shown below
Inside the Serial_DataLog click Binary and choose USB_DataLog.bin. Drag the file to the STLINK_V3M
Once the drag & drop is completed, open the terminal window, in our case we open Tera Term. And choose the correct comm port and baud rate.
Once the port is set up, we can see the data received form the sensor is displayed in the console window. Below is the data received from the STWIN board.
Now let's move on to the software setup for the kit. The software which is required is the STM32 Cube IDE and STM32 Cube Programmer. This software can be obtained from ST official site. The installation of this software is straight forward. Once we have done with the installation, we can first try to run the STM32 Cube Programmer. Make sure that the STLINK is connected to the board and the USB cable is connected as well.
Once we have all the connection in place, we can click the connect button
The above video shows the functions available in the STM32 Cube Programmer. By using the STM32 Cube Programmer, we can directly upload the .bin file to the STWIN board as shown in the above video. The other way to upload the program is by using the STM32 Cube IDE, whereby the code is compiled and downloaded later.
The simple project that I planned to build is to integrate the STWIN sensor kit to the safety helmet. This can be applied to various industries such as oil & gas, construction, and many other related industries as well. The main objective of building this project is to monitor the environment of the worker working space or area. Most of the time we are unaware of the environment that we are working at. The normal practice is that we will do a visual inspection before we start to work. This eliminates about 60% of the risk. But what happened most of the time is that we do not pay much attention to the noise, temperature, and other small parameters that might have high impacts on our health. For instance, people who work in a very noisy condition for a short period of time are still considered. But imagine if a worker that needs to be working in a very noisy condition for a very long period of time. This will surely have an effect to their hearings. Hence by implementing this project, I strongly believe that it will benefit the workers.
My initial plan for this project was to create a simple app that can monitor the environment of the worker through wireless communication. But since the kit comes without the WIFI module, I make few adjustments. Whereby the environment data of the worker will be logged in an SD Card and later will be analyzed either through the python or MATLAB.
I am in the midst of designing a holder that can attach the STWIN Kit to the helmet, will update it once I complete with the design and 3D printing. The image below is the initial stage of the development of the project.
| STWIN placement on the helmet | A better view of the placement of the sensor |
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The logging of the data will be accomplished using the High-Speed Data Logger. Luckily the STWIN library has the HSDatalog example which can be downloaded from their official site. For the analysis of the data, I have decided to use the MATLAB. First, we need to make sure that we have the SD card formatted to FAT32 and 32Kb file allocation. Once that is ready, next, we can move on to install the software on the STWIN. For this, we will use the STM32 Cube Programmer. The software can be found in the location as shown in the figure below
Once the location of the binary file is confirmed, next we can start to program the STWIN kit using the STM32 Cube Programmer.
After the programming is successful, a pop window will come and indicate either the programming is successful or failed. The pop window will look as shown in the figure below.
Next, we insert the SD card into the STWIN and connect to ST BLE Sensor App. The video below shows how it is done.
Inside the app we can choose the sensor that we want to monitor. Below is the snapshot of the sensor.
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Once, finished with the datalogging, the SD card can be removed and plug into the PC for data analysis. In this project, we will use the MATLAB. The folder for the MATLAB files can be found as shown in figure below
A new window will open as shown in the figure below
Next, click the Menu or press CTL+O to open the folder that contains our data. Once the folder is selected, we can see the window change as per the figure below
Referring to the figure above, the left side is the type of sensor that we have selected to log the data through the ST BLE Sensor app. Next, we can try to click on each of the sensors to check the data. The figure below shows the screenshot of the sensor data
| LPS22H - Temperature | LPS22H - Pressure |
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| STTS751 - Temperature |
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| HTS221 - Humidity | HTS221 - Temperature |
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| IIS2DH - X axis | IIS2DH - Y axis | IIS2DH - Z axis |
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| IMP34DT05 | MP23ABS1 |
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Next, the data can be put into further analysis to extract the information. And lastly on the power consumption, the STWIN only uses 0.046A to power the device. Th figure below shows the current voltage graph. The device is using very low energy and hence it can be easily run using the battery.
In conclusion, the STWIN kit offers a lot of insight into the IoT technology. The kit is a very good beginning for the engineer or makers who wish to apply IoT for their machines or other monitoring purposes. This kit can be made as a reference for other future development of IoT devices such as the energy monitoring devices and many more. One thing that I think which can be improved on the ST BLE Sensor is the sample app. The readily available sample app is designed for STEVAL-MKSBOX1V1. It would be very nice if the option is given to choose the sensor that is available for both STWINKT1A and MKSBOX1V1. Apart from that, the app itself is very easy to use and offers a lot of functions. I do feel there is a lot of things to be explored in terms of the software and tuning it to work for the desired or specific application.
Lastly, I would like to thank ST and element 14 for choosing as one of the road tester to review this product. Hope this review will be beneficial for others as well. And will update this roadtest once I have finished with the design and 3d printing of the holder for attaching the STWIN kit and safety helmet together.
Thank you.
