Introduction & Unboxing
I have just received the Vibration Sensor Kit in the mail! Just in time this weekend for me to experiment my first tests!
In the box, we have the vibration sensor itself (VS-BV203-B) bundled with a Nucleo Board (NUCLEO-H743ZI) and a Bluetooth Expansion Board ().
Let’s go through each item together!
Thank you to the sponsor KEMET for this experiment.
(I was confused at first due to the labelling but I realised that the Tokin brand is owned by Kemet)
The vibration sensor is packaged in a small but simple cardboard box.
The text on top states that it is part of the “VS Series”. There are many types of vibration sensors in the VS Series and there is also a sticker at the side to indicate which model is in this box (VS-BV203).
In the box, we have the vibration sensor itself wrapped in plastic. It also comes with a hardcopy instruction manual.
While we are at it, these are the relevant documents for the Kemet/Tokin VS-BV203-B vibration sensor which you can find online:
Unfortunately, the instruction manual contains a lot more information that cannot be found online. It is also stated in the manual that it “may not be copied without direct permission from TOKIN” so I am not sure if I am allowed to scan a soft copy for you all to see.
Nevertheless, I will state some facts about this sensor which I think are important.
The instruction manual states it is of a “Piezoelectric” sensor type. And in the datasheet, this graph shows that the sensor can detect a frequency range from 10 Hz up to 15kHz.
Note also that the resonant frequency is rated as above 30Hz, which you can see from this sensitivity graph below. This means that the sensor is slightly less sensitive at low frequencies and performs normally above 30Hz.
Prior to receiving the kit, I also tried to find out what connector to use but it is not stated in the online datasheet. The illustration appears to be a JST connector of some sort.
With hands on the actual product, this is how the connector looks like. I think some of you have also talked about it in the forums. It is tiny with a pin pitch of 1 mm!
The hardcopy manual recommends these connectors to mate with the sensor:
But it was inconvenient for me to order and wait for a connector. I decided to make do with whatever I had at home.
My last resort will be to cut the connector off (Spoiler: I managed to keep the connector intact)
Main thing to note that the holes are also extremely slim. Your typical breadboard wires are way too fat for it. I had those small 28 AWG wire-wrapping wires also, yet it could not fit in, it was still too big!
I eventually found out that these common Female Header Pins will work well.
It can barely fit tightly into the connector, but it is indeed thin enough.
I just bent the side outwards and soldered the standard 2.54mm male pin headers to it.
Sweet! I have a nice adapter which I can easily remove and insert back in whenever I want.
The microcontroller board is the Nucleo Board, NUCLEO-H743ZI.
It has a Cortex M7 core with a maximum of 480MHz system clock frequency and it also supports DSP instructions. This is an extremely powerful MCU that is good since we will be using it for analysis.
To be pedantic, this is actually the NUCLEO-H743ZI2. The main difference between the NUCLEO-H743ZI and the NUCLEO-H743ZI2 is that the former has an ST-LINK-V2 while the latter has the newer ST-LINK-V3. But it should be noted that there are a few other differences too, such as the LED pinout and board layout.
It also came with a Bluetooth Expansion Board, .
The Bluetooth Expansion is a nice plus but I don’t have much experience with BLE. This board uses the BlueNRG-MS processor which is quite recent in the past 3 years too. I hope to try it out but only if I have extra time for this project…
I hope this post is useful for those of you who are getting started especially with the sensor hardware. I’m quite proud of my hacked-together adapter hehe.
I will be doing my first few experiments with the vibration sensor and the microcontroller. In the next post, I hope to share with you the “Hello World” of Vibration Sensors.