Trent - Evaluation Kit User Guide
LAIIER’s evaluation kits have been designed to help you evaluate our technology for whichever use case is required. This user guide will instruct you through setting up the relevant sensor hardware and software to allow for effective data collection and/or visualization.
This kit is the Trent Evaluation Kit that is suitable for measuring the level of any liquid within a container. Each kit comes with one Trent Evaluation Board plus a board enclosure and three Trent Sensors.
After following this user guide, you will be able to scope the performance of these sensors and test their suitability for your application.
Theory of operation
Our Trent Sensors are based on capacitive sensing. Conductive ink is printed into a unique pattern that creates three electrodes: An environment reference electrode, a liquid reference electrode, and a level electrode.
Trent Evaluation Board
The evaluation kit contains the Alfa Board PCB. This PCB has been manufactured specifically for the Trent Sensors and its future updates. It includes a microcontroller chip, FFC connector, power switch, and a Micro USB output port. You may notice an Arduino footprint has been used on the board which will allow for further capabilities in the future. The Micro USB port outputs serial data of the sensor's measurements which is explained in the instructions.
- 1 x Trent Evaluation Board / Alpha Board
- 1 x Board Enclosure
- 3 x Trent Sensors
- 1 x USB cable
The first step is attaching the sensor to the container in which you are going to measure the level of the liquid. You can simply use tape for this. Attach the sensor with the tongue facing downwards and the silver side facing the inside of the container.
- Open enclosure by squeezing the enclosure by its sides
- Ensure that you have the right board inside, it should be the Alfa Board
- Then, on the right-hand side of the board, open the FFC connector by flicking the black level upwards
- Slot the sensor inside
- Once it is secure, close the connector by flicking the black level down again
- Connect the cable to the computer with the USB cable
- Once connected, turn on the board, the LED should be green now
- Replace the enclosure
- We recommend the software CoolTerm, which you can download here and download the version according to the operating system you are using
- Once the Evaluation Board is plugged into a PC USB port and powered on, open CoolTerm
- Within CoolTerm, open Options
- Select the port where the LAIIER board is plugged in, the name should be similar to “usbmodem14301”
- Set the Baudrate to “115200”, Data Bits to “8”, Parity to “None” and Stop Bits to “1”
- If you need timestamps, open the Receive Options on the left hand pane and under Capture File Options, tick “Add timestamps to captured data”
- Click OK to save and then click Connect to start
- CoolTerm will now display the sensor’s readings
- To capture data in a txt file, go to the Connection menu, then Capture to Text/Binary file and then click Start
- Save the file to your directory
- When finished capturing data, navigate back to Connection, Capture to text/binary file, then Stop
- In order to plot the data with Excel, first open Excel and then within Excel, open the CoolTerm text file
- Select “Delimited” and in the next screen check “Tab” and “Space”
- Set the date format to “YMD” and then click “Finish”
- Insert a column next after column “C” to specify the time in seconds
- Readings are roughly 18 times a second, so create a sequence as shown
- Select all 4 columns C to F for plotting
- Plot a scatter graph
- Format the scatter graph to what you require
- The first column (D) is the level data
- The second column (E) is the liquid reference data
- The third column (F) is the environment reference data
Once you have everything set up, you are ready to conduct your experiments. Our Trent Sensors are able to measure the level of a range of liquids, so you can. You should see a change in numbers within CoolTerm. It is also important to note when exactly you have introduced a change for the sensor to detect so it will be easier to analyse results afterwards, e.g. dropping liquid on the sensor 10 seconds after the sensor is recording data.
In order to make sure sensors are installed correctly and allow for efficient experimentation, follow these steps:
- Make sure any surface is dust and debris-free before sticking the sensor down to improve adhesion
- If testing is on a delicate surface, test a small part of the adhesion first to prevent potential damage
Between experiments, make sure all sensor segments are wiped clean with water (distilled is the best) and dried if they got in contact with any liquid. This will ensure all initial readings of the sensor are at the normal level.
Make sure all values are what you expect them to be with some quick sanity checks. For example:
- Values should start off stable and at the initial values (ie. 1023 for all 12 sensing segments)
- Values should be between the minimum and maximum points
- When a conductive liquid is sensed, it should have a noticeable change in signal
If there are any issues or questions that have not been answered in this guide, contact email@example.com and we will get back to you shortly