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This article explores a new open-source method for developing and manufacturing high-quality scientific equipment suitable for use in virtually any laboratory. A syringe pump was designed using freely available open-source computer aided design (CAD) software and manufactured using an open-source RepRap 3-D printer and readily available parts. The design, bill of materials and assembly instructions are globally available to anyone wishing to use them. Details are provided covering the use of the CAD software and the RepRap 3-D printer. The use of a (partly open-source) Raspberry Pi computer as a wireless control device is also illustrated. Performance of the syringe pump was assessed and the methods used for assessment are detailed. The cost of the entire system, including the controller and web-based control interface, is on the order of 5% or less than one would expect to pay for a commercial syringe pump having similar performance. The design should suit the needs of a given research activity requiring a syringe pump including carefully controlled dosing of reagents, pharmaceuticals, and delivery of viscous 3-D printer media among other applications.

• The source code for the linear actuator and pump server are housed here: https://github.com/mtu-most/linear-actuator
• If you are customizing your own pump you will need MOST SCAD library files found here: https://github.com/mtu-most/most-scad-libraries Download them all and put them in the same folder as the files for the pump -- then the SCAD will compile correctly.
• For example STL files see https://www.youmagine.com/designs/syringe-pump
• See also: Lynch open source syringe pump modifications - includes 1) Escape mechanism to move pusher block without running the motor, 2)Open syringe clamp to allow easy removal, 3) Arduino Control with EasyDriver.
• To calculate the value of doing work on projects like this see:Quantifying the Value of Open Source Hardware Development

E. Hunt D80 Presentation on the Open-Source Syringe Pump

Materials and Tools

Note: This page describes the mechanical build and software installation. The paper describes the electronics as it was originally implemented. This method is not maintained anymore. It is now recommended to use a 3-D printer controller such as a RAMPS or Melzi and Franklin to control the device. The old method is detailed in the Discussion tab of this page.

Materials 3-D Printed Count Motor End 1 Carriage 1 Plunger Holder base 1 Plunger Holder tab 1 Body Holder 2 Idler End 1 Motors & Metal Count NEMA17 motor 1 5mm x 5mm shaft coupling 1 625z ball bearing 2 LM6UU linear bearing 2 M3 x 10mm socket head cap screw 6 M3 x 20mm socket head cap screws 4 M3 x 40mm socket head cap screws 4 M3 hex nut 13 M5 hex nut 5 M5 threaded rod 0.2 m 1 6mm A2 tool steel 0.2 m 2

Tools M3 allen key 3mm drill bit

How to Build an Open-source Syringe Pump

1

Secure motor into the motor end using 4 M3 washers and 4 M3 x 20mm socket head cap screws.

2

Insert the 2 metal rods into motor end, then secure them in place with 2 M3 nuts and 2 M3 x 10mm  socket head cap screws.

3

Insert the threaded rod into the coupler halfway, the other half should be on the motor, secure it.

4

Hollow out the two ends of the carriage, with a handheld drill bit or knife to make a hole in the plastic

5

Snap the linear bearings into place on the hollowed out ends of the carriage. Then insert an M5 nut into the nut-trap on the bottom of the carriage.

6

Attach the base of the Plunger holder to the carriage with 2 M3 nuts and 2 M3 x 10mm socket head cap screws.

7

The connected separation container.

8

Slide the carriage onto the threaded rod and make sure the two metal rods fit into the linear bearings

9

After the carriage is midway down the threaded rod, thread two M5 nuts onto the threaded rod.

10

Insert the two bearings into the circular slots in the idler end.

11

Now slide the idler end onto the rods and secure it with two more M5 nuts on the end of the threaded rod. Push the two nuts already on the rod up to the idler end to secure it.

12

Insert the syringe body into the body holders, then slide the plunger into the base of the plunger holder

13

Using four M3 x 40mm bolts, four M3 washers, and four M3 nuts secure the two holding pieces to the idler end of the pump. Put two nuts it the top of the holder closer to the carriage and two nuts in the bottom of the holder against the idler end.

14

Insert the tab of the plunger holder on top of the plunger to secure it to the pump and prevent slipping when in use.

Controller: Connection and Calibration

This is a description for using Franklin to control the device. Latest version available for free Github.

(The paper describes the electronics as it was originally implemented. This method is no longer maintained. It is now recommended to use a RepRap 3-D printer controller such as a RAMPS or Melzi, which you can pick up online and Franklin to control the device. The original instructions are available in the Discussion tab.)

The motor must be connected to the control board on the terminals that are intended for the first axis (normally called X). In Franklin, load the profile for the board you have, then set up the profile and calibrate the pump:

1

Set the nuber of temps to 0, position axes to 1, and extruders and followers to 0.

2

Disable both limit switches.

3

Set the coupling to 100 step/mm and the speed limit to 20 mm/s.

4

Set the switch position to 0, then home the pump. This sets the current position to the switch position.

5

Select the x position input. Then press arrow up and down to move the pump in small steps page up and down to move it in larger steps.

6

The pump should push liquid out when moving in the positive direction. If it is moving in the wrong direction, invert it.

12

After setting the correct coupling, adjust the maximum speed to a value that works (if it is too high, the motor will skip) and name and save the profile. Also set this profile as default.

13

Right-click on the export link and save the target to a location on your computer where you can find it. Use this file to restore the profile if you need it.

14

If you want the interface to be correct (of course you do), open the profile in a plain text editor and change the unit_name setting from mm to mL. Save it and import the new settings. Note how all the units in the interface change.

The pump is now ready to use. You can use the x position entry to move it manually, or upload G-Code which moves the X coordinate to move it in a pre-programmed pattern. A simple G-Code example is:

G91 ; Use relative positioning.
G1 X10 F600 ; Push 10 mL at 600 mL/min (10 mL/s).
G1 X1 F120 ; Push 1 mL at 100 mL/min (2 mL/s).
G4 P500 ; Wait 500 ms.
G1 X1 ; Push another mL at the same speed.
G1 X10 F600 ; Repeat.
G1 X1 F120
G0 X-5 ; Pull back 5 mL at maximum speed.

Minimum Pump Rate

The minimum pump amount is a single step of the motor; how much that is depends on the size of the syringe. Here the lead screw has a pitch of 0.8mm and the motor does 3200 microsteps per revolution, so one step is a plunger movement of 0.8mm/3200=250nm. The cross section of a 25ml syringe is around 4cm², so one step is the product of those, which is 0.1mm³=0.1μL.

There is no minimum value for the speed that the pump can go, but if you get near the step size, the flow will be in noticeable steps instead of continuous. For example, if you want 1μL/min, it will do one step every 6 seconds.

See also

• Lynch open source syringe pump modifications - includes 1) Escape mechanism to move pusher block without running the motor, 2)Open syringe clamp to allow easy removal, 3) Arduino Control with EasyDriver
• Open-source Lab
• Building research equipment with free, open-source hardware
• Open source science
• Open source optics
• Open source 3-D printing of OSAT
• Open-source hardware
• Syringe pump literature review
• Open Source 3-D Printed Nutating Mixer
• 3-D printable open source dual axis gimbal system for optoelectronic measurements
• Ystruder: open source multifunction extruder with sensing and monitoring capabilities
• Open Source Digitally Replicable Lab-Grade Scales
• Open Source Vacuum Oven Design for Low-Temperature Drying: Performance Evaluation for Recycled PET and Biomass
• Open Source 3-D Printed ISO 8655 Compliant Multichannel Pipette
• Open Source Scientific Bottle Roller
• Open Source Cold and Hot Scientific Sheet Press for Investigating Polymer-Based Material Properties
• Open Source Inert Gas Glove Box

Coupled Initiatives

• Modified Open Source Syringe Pump Parts - by Dylan Lynch
• Open pump -Help to make better devices for healthcare and lab environments
• Open Syringe Pump on Hackaday by naroom - Arduino controlled
• Will Patrick's OS syringe pump at MIT
• Hedron Paste Extruder Project
• Trial database uploads:
  • http://3dprint.nih.gov/discover/3dpx-000674
  • https://www.youmagine.com/designs/syringe-pump
• Universal paste extruder
• Bricoleur Clay Extruder, Open Source
• E-steps-per-mm method - Method for calculating the E-Steps-per-mm of an extruder based on the Open Source Syringe Pump.
• LVESPmm - Python script with GUI for calculating the E-Steps-per-mm of an extruder based on the Open Source Syringe Pump.

In the News

• Science Just Got Cheaper (and Faster): Design Library Lets Researchers Print their Own Syringe Pumps - Michigan Tech News
• Doctors Could 3D Print Their Own Tools For a Fraction of the Cost - Gizmodo, Gizmodo India, Gizmodo Australia, USA News
• 3D Printed Syringe Pumps are Perfect for Cash Strapped Scientists - Motherboard
• 3D Printable Syringe Pump Design Lowers Lab Costs - Med Device
• 3D-printed syringe pumps could cut the cost of scientific research - Gizmag
• 3-D printing leads to another advance in make-it-yourself lab equipment - Phys.org
• Make-it-yourself lab equipment with 3-D printing- Nanowerk
• 3D-printed syringe pumps could cut a cost of systematic research- World News Source
• Researchers could now 3D print their own syringe pumps using a RepRap - 3Ders
• Doing science just got cheaper -- and faster - Science Codex
• RepRap: Open Source Lab Equipment Makes Science Cheaper - And Faster - Science 2.0
• 3D Printed Syringe Pumps Cost a Mere Fraction of Traditional Pumps - 3D Print

"Another day, another phenomenal addition to the list of practical, hype-less, real, tangible, 3D printable tools that are bound to bring on some welcome changes. This time, it's the scientific community that can sing praises and raise their glasses as they're about to reap the benefits – and save a bundle – on 3D printed syringe pumps."

• Doing science just got cheaper -- and faster - ECN
• Doctors Can 3D Print Syringe Pumps for a Pittance Now - Softpedia
• 3DP Leads to Another Advance in DIY Science Equipment - Engineering.com
• The medical world could become much cheaper thanks to 3D printing Inside 3DP
• 3D-printed syringe pumps could cut the cost of scientific research -- Electronic Engineering Journal
• Michigan Tech Offers Free Designs For 3D Printing Lab Gear - Technology Century
• 3D-Printed Lab Equipment Stretches Research Budgets- Polymer Solutions Newsblog, Lab Manager
• New open source designs make lab work affordable - The Lode
• Science just got cheaper (and faster) - Today's Medical Developments
• Open-Source Syringe Pump Library - Replicator World
• Open source syringe pump - Raspberrypi.org
• Open-Source Syringe Pump #piday #raspberrypi @Raspberry_Pi - Adafruit
• Open source syringe pump - FreeIO.org
• How 3D Printing Can Reduce Medical Expenses - Nation Swell
• A TEMPLATE LIBRARY ALLOWS RESEARCHERS TO PRINT IN 3D, THEIR OWN SYRINGE PUMPS - InfoHighTech (France)
• Open Source Hardware soll durch Kosteneinsparung Medizin revolutionieren - 3Druck (Germany)
• 3D printed syringe pump - What Next (Poland)
• Injection pump open source 3D printing model library to help scientists provincial money - Maker8 (China)
• 3D打印,模型库,注射泵,开源 - 中关村在线办公打印频道 - oa.zol.com.cn (Zhongguancun Online (zol.com.cn) - the world's first Chinese technology portal, Greater China's most commercially valuable IT professional portal.)
• Científicos ahorran millones en equipo con simple invento - Electronics Online (Spanish)
• 3D Printed Open Hardware Syringe Yields $800M Value, Study Finds- 3D Printing Industry
• 'Open-hardware' pioneers push for low-cost lab kit -Nature News