Minute - April

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• Met with Prof. Lima to discuss about current objectives.
• With the help of Prof. Lima and machine shop technician, we built five cylindrical chambers with input filter holder and output quick-release insert valve.
• We setup the pump system (All tubing and valve manifolds)
• All parts seemed to fit perfectly.
• Automatic arduino control system did not function properly - and on top of it, we fried an arduino chip (Oops)
• Re-uploaded arduino code to the spare arduino.

• Link: Cylindrical chamber

• Re-examined the control system to prevent any further damage.
• We concluded that 2 Amps from the power supply may be the problem, so we decided to use different power supply (24V 0.5A)
• Wired up automatic arduino control system and solenoid valves.
• Confirmed that the system functions properly with the new arduino chip.
• Tested solenoid valve functions.
• Automatic pump operation did not work - we need to find a new relay or use transistors for 24V relay that we currently have.
• We found out that we need to modify our code since we are using different pump now.

• We wrote an arduino code for stepper motor control (make a complete turn forward and backward)
• Uploaded the code and wired up the system.
• Since our motors use 24V, we need to connect an external power to the motor shield.
• Confirmed that the motor works.
• Be very careful about wire configuration - wires must be connected in right order

• Link: Pump system with cylindrical chambers
• Link: Solenoid valve control with arduino
• Link: Stepper Motor Testing

• Air pressure within the chamber often caused back-flow of liquid
• Therefore we needed to have a sterile air inlet / outlet
• Machined the cylindrical chamber rids to install an air filter
• Installed a socket for 0.2 Micrometer in-line filter
• Back-flow of liquid is minimized, but pump's flow rate must be reduced to 5
• Modified the arduino code (Made each filling phase longer [55 seconds each])

• When evacuating liquid, one chamber is always left behind due to uneven rate of evacuation through the valve manifold
• Liquid in the last chamber does not evacuate completely due to excess air supply through other three chambers
• The set up functions well with four chambers at most
• Decided to use only four chambers

• Link: Installation of air inlet/outlet filter

• Confirmed that the relays function properly to operate pumps
• Valve control #3 of the original board was broken
• Needed to make a new board

• Soldered a new control system board that incorporates valve control, pump control, and arduino on a same board

• Link: New control system board

• Started building the Drawbot
• Found new stepper motors with greater torque

• Conducted final testing of the pump system.
• Decided to use bigger air filters to let more air in to prevent back flow.
• Everything works well, done with the pump system !

• Link: Final system test

• Drawbot competition
• Coded the Drawbot - drew HelloWorld and triangle

• Link: Drawbot Competition

• We need to make an instruction manual
• Get ready for shipping
• Find IV bag with 3 Outlets

• Pump, instruction manual, and chamber system shipped!!

Link here- picture of wrapped and packed stuff. *Link to instruction manual pdf**