Our FlowIO Journey

2/25/24

We got the FlowIO kit from Rosalie, which was more than halfway done. We have started to continue to assemble it. I will post an update soon.

I need to connect the pressure sensors next to the inlet valve. If anyone knows where I can purchase Epotek 301-2 epoxy please let me know.

03/04/2024

I am working on a soft robotics project for a high school science fair. We needed a light-weight pneumatic control mechanism to be able to efficiently actuate the robot. I came across the FlowIO module, and it seemed to be a perfect fit for us. I reached out to Ali, and he connected me with Rosalie. One week later, I got hold of a FlowIO device from Rosalie! Let the fun begin!

I have two goals with this work. (1) Assemble the FlowIO chassis (2) Use it as the drive module for our soft robot.  This will need us to adapt our robot design so that we can mount the FlowIO.  This blog focus on the first goal

The prototype I got from Rosalie has been almost assembled. This made my work a lot easier.  

Bootloader update

To start, I wanted to update the bootloader. First, I followed these instructions to install the Arduino IDE and Adafruit Bluefruit Feather board BSP. With these done, I am ready to update the bootloader.

I hit the problem reported by Rosaliein her blog. I had to detach the FlowIO board in order for the update to go through.  Otherwise, it appears the update process will hang and halt with the FlowIO board attached.

One thing to note is that, once the bootloader is updated, simply disconnect the Feature board from the laptop and re-attach the FlowIO board. The bootloader only needs to be updated once.

From now on, I can control the power of the FlowIO by pressing the on/off switch on the FlowIO board, as illustrated in this picture.  

After this step, I felt I had a good understanding of how FlowIO worked and how to control it.

Hardware Test

Next, I wanted to perform the hardware sanity checks. I used the example tests in the library. 

I initially had a hard time determining the inlet valve and outlet value.  The connection I first made was incorrect, ie, had the inlet valve and outlet valve swapped. 

I later figured out the problem, the correct connections look like this:

As the tests ran, I found that the Inflation test and Vacuum test were failing. Upon further examination, I found that the valve cap and pressure sensor tube were not installed. This is the reason why the Inflation and Vacuum Tests did not reach the desired pressure.

One thing to note is that it is important to dig into the test code to further understand how the FlowIO valve and motors are controlled. I read the code, modified some parameters, and observed how the tests changed. This provided me an opportunity to learn how to control the device and is beneficial when I program it to control my soft robot later on.

Valve Cap Assembly

I followed the valve cap and pressure sensor tube assembly instructions with some minor tweaks.

First, I could not find the recommended glue. Instead, I used the Gorilla glue which I purchased from Amazon. I also 3D printed a tube. Before applying the glue, I cleaned up the surface using 70% Isopropyl Alcohol.