Download Revised Supplementary Material - Final

Supplementary Material for:
Pneumatically Modulated Liquid Delivery with Feedback Control
Electronics
Table S-1: A summary of the Arduino Uno microcontroller pin connections to each component in the PMLDS.
Arduino Uno Pin
Reset
3.3V
5V
Function
Not connected
Not connected
Power supply
GND
Ground
GND
Vin
A0
A1
A2
A3
A4
A5
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
GND
AREF
Ground
9V input
Not connected
Not connected
Not connected
Not connected
SDA
SCL
TTL RX
TTL TX
LCD
LCD
LCD
LCD
LCD
LCD
10’s switch
10’s switch
1’s switch
1’s switch
Not connected
Not connected
Not connected
Not connected
Component Pin
LCD Pin 2, LCD Pin 15, 1’s increment, 1’s decrement,
10’s increment, 10’s decrement, MAX517 Pin 6,
MAX517 Pin 7, MAX517 Pin 8, MAX232 Pin 16
LCD Pin 1, LCD Pin 3, LCD Pin 5, LCD Pin 16, MAX517
Pin 2, MAX517 Pin 5, MAX232 PIN 15
Voltage regulator
Voltage regulator
MAX517 Pin 4
MAX517 Pin 3
MAX232 Pin 12
MAX232 Pin 11
LCD Pin 14
LCD Pin 13
LCD Pin 12
LCD Pin 11
LCD Pin 6
LCD Pin 4
10’s increment
10’s decrement
1’s increment
1’s decrement
Figure S-1: The electrical diagram with the microcontroller and EPC housed in a single 3x4x5
inch aluminum box with a 24 V, 0.9 A power supply and a voltage regulator.
Pressure Vessels
Five pressure vessels were considered for use with the PMDLS. A 50 mL Nalgene
centrifuge tube was tested, but based on documentation it could not hold 50 PSIG of pressure.
Theoretically, the EPC unit is supplied with house air, which is down regulated to 50 PSIG. If the
EPC unit were to fail, 50 PSIG could be supplied to the pressure vessel, while only a maximum of
15 PSIG is supplied when the EPC unit is in use. A pressure vessel capable of at least 50 PSIG
was desirable for safety considerations, and necessary if higher flows and pressures were
needed in future applications. A 500 mL Nalgene bottle was also considered, but a noticeable
deformation was observed under 15 PSIG of pressure.
A glass, 350 mL round bottom flask was found capable of holding 150 PSIG (Chemglass
Scientific Equipment, Inc.). The glass round bottom flask had adequate volume to run
continuously for several days at 30 μL min-1 and a visible indication of liquid level in the vessel.
An inert plastic “T” connector (P-714, IDEX Health & Science) was used to connect the liquid
flow and pressure line to the cap provided with the round bottom flask. The plastic cap was
drilled and tapped for an adaptor (U-511, IDEX Health & Science) to connect to the “T.” Plastic
capillary tubing (360 μm OD, 150 μm ID) was inserted through the “T” and into the round
bottom flask for the liquid connection, while 1/16 inch OD thick-walled PTFE tubing was used
for the gas connection. The completely assembled round bottom flask can be seen in Figure S2A.
A metal, refillable spray paint canister rated for 100 PSIG was evaluated. The canister
was modified slightly to hold 50 mL plastic centrifuge tubes and 1/16 inch OD PTFE tubing for
liquid flow. The 50 mL centrifuge tube offers improved reusability of the pressure vessel
without flushing or rinsing, minimizes cross contamination, and the same containers can be
used for solution preparation. Figure S-2B shows the modified refillable spray paint canister
with liquid and gas connections. Again, a complete parts list can be found in Appendix A. The
metal canister is not transparent and the liquid level inside the 50 mL plastic centrifuge tubes
cannot be monitored visually. With the exception of the 500 mL Nalgene bottle, the three other
pressure vessels could be used depending on the application and experiment, but the glass
round bottom flask and metal canister are better suited if a failure occurs and easily adapted
for applications requiring higher pressures and flow rates.
A custom built pressure vessel with designed to minimize dead volume and combine the
advantages of the clear, round bottom flask with the refillable spray paint canister. Figure S-3
shows the custom pressure vessel used for collecting flow rate data to compare to the syringe
pump. The pressure vessel is capable of holding 100 PSI of pressure and uses a snap tight lid,
which acts as a failsafe for over pressure. The empty pressure vessel has a dead volume of
approximately 90 mL, but the 50 mL centrifuge tubes occupy a approximately 75 mL when filled
with 50 mL of liquid, resulting in a filled dead volume of 15 mL.
Figure S-2: Pressure vessels for the PMLDS: (A) a 350 mL glass round bottom glass rated to 150
PSIG and (B) a refillable spray paint canister rated for 100 PSIG. An inert plastic “T” connection
is used with the round bottom flask for fluidic and gas connections. PTFE capillary tubing (360
μm OD, 150 μm ID) was used as the liquid connection for the round bottom flask and thickwalled PTFE 1/16 inch OD tubing for the gas connections. The refillable spray paint canister
used only thick-walled PTFE 1/16 inch OD tubing for both the liquid and gas connections.
Figure S-3: A custom pressure vessel with a window for viewing the contents of the container
during use. The empty pressure vessel has a dead volume of approximately 90 mL and a filled
dead volume of 15 mL
Parts List
Table S-2: The complete parts list for the PMDLS.
Part Description
24V, 0.9A Power Supply
Toggle switch Mom-Off-Mom
Toggle switch On-Off DPST
Header pins, 36 pos
Terminal crimp connector
Female spade crimp connectors
Fork Tongue crimp connector
10K Ω Resistor
2K Ω Resistor
10 Ω Resistor
0.1 μF capacitor
1 μF capacitor
RS232-to-TTL chip
1-CH 8-Bit I2C DAC Chip
Microcontroller
Qty
1
2
1
5
7
3
1
6
1
1
2
5
1
1
1
4P4C Modular Jack PC Mount
1
16-pin DIP Socket
1
8-pin DIP Socket
1
Power Connector Port
4 x 5 x 3 in Aluminum utility box
DB9 Male connector
White on Black LCD Display
1
1
2
1
2
8
2
2
4
8
8
8
7
1
2
2
1
1
4
1
6 channel 4'' jumper cable
Nylon 1/8 inch spacers
M2x4 screw
M2x16 screw
M2 nut
M2 washer
M3x10 screw
M3 nut
M3 washer, zinc
M3 nylon washer
4-40 socket cap screw ¼ inch
4-40 metal washer
4-Pin KK Connector (0.156’’ pitch)
3-Pin KK Connector (0.156’’ pitch)
Connection terminal female
2-Pin housing with locking ramp
Part Number
ZPSA20-24
A105SYZQ04
M2021SS1W03
68001-436HLF
08-50-0107
19003-0107
31N2550
Manufacturer
TDK-Lambda
TE Connectivity
NKK Switches
FCI
Molex
Molex
Newark Electronics
CFR-25JB-10K
MFR-25FBF-2K10
CFR-25JB-10R
C315C104M5U5TA
Yageo
Yageo
Yageo
Kemet
FK24Y5V1H105Z
MAX232CPE+
MAX517BCPA+
Uno
TDK Corporation
Maxim
Maxim
Arduino
TM3RA-44(50)
1-390261-4
1-390261-2
Hirose Electric Co Ltd
TE Connectivity
TE Connectivity
JR-101
AU-1028
G17S0910110EU
LCD-00709
Multicomp
Bud Industries
Amphenol
Sparkfun
Sparkfun
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
McMaster-Carr
PRT-10366
94639A299
92005A033
92005A037
90591A111
91166A180
92005A120
90591A121
91166A210
95610A130
92949A106
94744A155
09-50-3041
09-50-3031
08-52-0072
22-01-3027
Molex
Molex
Molex
Molex
3-Pin housing with locking ramp
4-Pin housing with locking ramp
Connection terminal female
2-Pin header with friction lock
3-Pin header with friction lock
4-Pin header with friction lock
4
1
18
1
4
1
22-01-3037
22-01-3047
08-50-0114
22-27-2021
22-27-2031
22-27-2041
Molex
Molex
Molex
Molex
Molex
Molex
Jumper shorting connector
2
STC02SYAN
Sullins Connector
Solutions
1
SS-400-1-2
Swagelok
1
SS-100-1-2BT
Swagelok
1
SS-200-61-1
Swagelok
2
96371A203
McMaster-Carr
1
92141A029
McMaster-Carr
1
91525A230
McMaster-Carr
1
5 ft
5 ft
5 ft
5 ft
1
2
1
1
U-511
1503
1478
1932
1933
F-185x
P-440
F-331x
11181
1
CG-1880-42
IDEX Health & Science
IDEX Health & Science
IDEX Health & Science
IDEX Health & Science
IDEX Health & Science
IDEX Health & Science
IDEX Health & Science
IDEX Health & Science
Eastwood
Chemglass Scientific
Equipment
1/8 inch NPT male to 1/16 inch
Swagelok Male stainless steel
1/8 inch Swagelok male to 1/8 inch
NPT female bulkhead stainless steel
1/8 inch Swagelok male to 1/16 inch
Swagelok male bulkhead stainless
steel
5/16 inch ID PTFE washer
5/16 inch ID, 5/8 inch OD stainless
steel washer
Large fender washer, 1.25 inch OD,
5/16 inch inner
1/8 inch NPT to ¼-28 Male
1/16’’ OD, 0.030’’ ID PTFE tubing
1/16’’ OD, 0.008’’ ID PTFE tubing
360 μm OD, 100 μm ID HPFA tubing
360 μm OD, 150 μm ID PTFE tubing
360 μm ID capillary sleeves
10-32 coned Bulkhead Union
10-32 PEEK Nut and Ferrules
Billet refillable spray paint can
350 mL glass round bottom flask
RS-232 Communication with a computer
As of version 2.0.0, the NRL-PMLDS software and hardware is capable of communicating with a
computer, or similar device, via the RS-232 protocol. A standard D-sub miniature 9-pin
connector (DB9) is mounted on the back of the NRL-PMLDS with the following pin configuration
for serial communication:
Table S-3: Pin configuration for the DB9 connector
Pin
1
2
3
4
5
6
7
8
9
Function
Not connected
TX
RX
Not connected
Ground
Not connected
Not connected
Not connected
Not connected
The NRL-PMLDS can be connected to a computer with a standard DB9 serial cable. A null
modem, or crossover, cable is not necessary. A Serial-to-USB adaptor can also be used to
enable USB communication with a computer but USB is not natively supported within the NRLPMLDS system as of version 2.0.0. The flow rate selector switches can be used to set the target
flow rate while the NRL-PMLDS is in serial communication with a computer, or similar RS-232
enabled device. Serial communication offers greater control and functionality over the simple
PID control and target flow rate selection interface.
The NRL-PMLDS communicates via the RS-232 protocol at 9600 baud rate, 8 bits, 1 stop bit, no
parity, and no hardware flow control. All commands must be terminated with a new line
character (“\n”) and all responses from the NRL-PMLDS are terminated with a new line
character. Table 2 outlines the commands recognized by the NRL-PMLDS. All other commands
are ignored and any additional characters after the command are ignored. The number sign
(“#”) in the commands are replaced with digits from 0-9 and are simply placeholders for the
value. Floating point numbers can be sent as decimals or in scientific notation. Commands are
not echoed back.
The commands DF=##.#, KP=#.##E#, KI=#.##E#, and KD=#.##E# can only be set, or written, up
to a combined total of 100,00 cycles. These values are stored in the internal EEPROM of the
microcontroller and have a finite number of write operations. Use caution to minimize
excessive calls to these commands. It is also recommended to send the restart command (“|>”)
after setting the PID parameters.
Table S-4: Summary of commands recognized by the NRL-PMLDS using a 9600 baud rate, 8 bits, 1 stop bit, no
parity, and no hardware flow control. All commands must be terminated with a new line character (“\n”) and all
responses are terminated by a new line character.
Command
TF=##.#
TF?
DF=##.#
DF?
AF?
IF?
V=#.##
V?
P=##.#
P?
KP=#.##E#
KP?
KI=#.##E#
KI?
KD=#.##E#
KD?
||
|>
Description
Sets the target flow rate in μL/min, range: 10-99 μL/min, values greater than or
less than the acceptable range are set to 99 and 10 μL/min, respectively.
Gets the target flow rate in μL/min
Set the default flow rate in μL/min, range: 10-99 μL/min, values greater than or
less than the acceptable range are set to 99 and 10 μL/min, respectively. The
default flow rate is the target flow rate on power up. This value is retained during
power cycling.
Gets the default flow rate in μL/min. This value is retained during power cycling.
Gets the average flow rate in μL/min, flow rates greater than 100 μL/min are
reported as 100 μL/min. The average flow rate is a 10-point, non-zero rolling
average to reduce the noisy measurements from the flow meter.
Gets the instant flow rate in μL/min, which is not part of the 10-point, non-zero
rolling average.
Sets the EPC control voltage in volts, range: 0-5 V, values greater than or less than
the acceptable range are set to 5 and 0 V, respectively. Values must be left and
right padded with zeros to match the proper length. The PID control must be
paused (“||” command) to set the control voltage.
Gets the EPC control voltage in volts.
Sets the pressure in PSI, range: 0-15 PSI, values greater than or less than the
acceptable range are set to 15 and 0 PSI, respectively. Values must be left and
right padded with zeros to match the proper length. The PID control must be
paused (“||” command) to set the pressure.
Gets the pressure in PSI.
Sets the Kp constant for the PID control. This value is retained during power
cycling. This value is unitless and does not have to be in scientific notation.
Gets the Kp constant for the PID control. This value is retained during power
cycling. This value is unitless.
Sets the Kp constant for the PID control. This value is retained during power
cycling. This value is unitless and does not have to be in scientific notation.
Gets the Kp constant for the PID control. This value is retained during power
cycling. This value is unitless.
Sets the Kp constant for the PID control. This value is retained during power
cycling. This value is unitless and does not have to be in scientific notation.
Gets the Kp constant for the PID control. This value is retained during power
cycling. This value is unitless.
Pauses PID control. The screen will replace “TF: ##.#” with “Paused”. In pause
mode, the control voltage and/or pressure can be set manually.
Resumes PID control. The screen will display the target flow in μL/min. The
control voltage and/or pressure cannot be set manually while PID control is active