KnowFlow Special Design



About: a maker

KnowFlow is an open source water monitoring device.

It is designed for environmental activists, researchers, students... anyone who wants to know the water quality using low cost and customized tools.


Once this is done we can test the water quality from the much deeper area. And the operation would be simplified.

We went to GZC, China to test our machine.

Material List

Bluno (DFR0267) x1

Gravity: Analog pH Sensor / Meter Kit For Arduino (SEN0161) x1

Gravity: Analog Electrical Conductivity Sensor / Meter For Arduino (DFR0300) x1

Gravity: IO Expansion Shield for Arduino V7.1 (DFR0265) x1

Gravity: I2C SD2405 RTC Module (DFR0469) x1

MicroSD card module for Arduino (DFR0229) x1

Gravity: Analog Signal Isolator (DFR0504) x1

SD/MicroSD Memory Card (8 GB Class10 SDHC) (FIT0393) x1

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: KnowFlow Assembling

KnowFlow is designed for environmental activists, researchers, students... anyone who wants to know the water quality using low cost and customized tools. It is based on arduino uno, currently can monitor 5 parameters: Temperature, pH, ORP, Electronic conductivities, Dissolved Oxygen, the data is stored on a micro SD card, or read directly on phone by Bluetooth (except for Dissolved Oxygen). All the modules are easy to change or add. Most of the sensor used is from DFRobot and Atlas Scientific, which are the main 2 sensor suppliers for Arduino users.

For more detail, you can go to the link below.

Know Flow Project


We had the problem with the suitability of our case and the hardware device, especially the power part and the port part.We deal with that by redesigning and enlarging the inner space.


Step 2: Under Water Bot (ROV)

We shaped the bot with PVC pipes and expanded plastic.

The bot got six motors to drive itself.

And we used wire for power supply.

Caution: It is important to test the bot indoor before planning a practice in natural water.

Step 3: Before Test Preparation

  1. We put a lot effort into the water-proof cover.

    sub-STEP 1

    we used HOT MELT to cover the joint parts of all sensors

    sub-STEP 2

    we made a larger case with PMMA and cover the joint parts with HOT MELT

  2. We also place a GO-Pro on the ROV.

Caution: PLZ sets the hole of the PMMA case at least 2mm larger in radius than the estimate. (1mm is not ok and that cost us a lot of time to shape the size of these holes)

Step 4: Testing

With some essential water-proof process, we got a beta test in a river.

After testing for about 30mins, the glue we used the protect the device cracked and water fill the container.

Even though the test failed we still got some data stored on the SD card.

We would analyze the data and improve our machine in the coming few days.

Be the First to Share


    • Made with Math Contest

      Made with Math Contest
    • Cardboard Speed Challenge

      Cardboard Speed Challenge
    • Multi-Discipline Contest

      Multi-Discipline Contest