Final Group Proejct: Water Clock


Our group's vision is to design and create a water clock which uses water levels to tell time.   Our design will consist of 3 acrylic columns, to indicate the hour, minute, and seconds of time.  The column will be filled to the appropriate level based on the current timing

The initial BOM for the water clock looks like

1PumpCirculate water to top resevoir
6DC Solenoid ValvesControl column water inflow and outflow
TubesCirculate water from botton to top resevoir
3Distributed Controller Boards (based on Neil's Step Response board)Control water level of each column
1Master Controller BoardKeep time and send command to column
3SensorsFeedback on water level


The main cost is from the valves and pump.  The pump is roughly $80 and the valves are about $25 each.  If we go with capacitance sensors, it would be practically free.  If we need IR or ultrasound sonar, this would add the cost of three such sensors.

Here are picture of the group testing various sensors: capacitance and sonar:

Capacitance                    Ultrasound

We saw a lot of noise and instability with the capacity sensors, even with the verison using a shield.  The utlrasound sensor had a beam that was lobe shape, so from time to time, it would bounce off the walls and result in noise.

Material Sources

The sensors are sourced from either IDC or Sparkfun.  The valves and pumps are purchased from McMaster and Amazon.


- Sensing with sensor is creating a lot of noise and the measurement is not consistent (adding water sometimes increases time constant, sometimes decreases it)
- Ultrasound sensor is bouncing off the walls of the column
- Uncertain if valve will release water in time
- Will valves react quickly enough for seconds column?

Schedule/ Tasks

- Test sensor
- Test valves
- Create controller boards
- Integrate