This section will discuss what is needed and how to build both Pneumatic Deformation Sensors. The following page has a bill of materials for sensor designs 1 and 2 and both breadboard and soldered versions of the circuit. The pages after that has step-by-step instructions for building all of the previously mentioned things.
The instructions for the circuits will require knowledge of reading a circuit diagrams and soldering skills. Tutorials for said things can be found here and here.
Materials:
Name | Quantity | Picture | Link | Notes |
Ecoflex 00-30 Silicone | 1 | Via Amazon | ||
Zip-Tie | 1 | Via Amazon | ||
1/8" Tubing | at least 2" | Via Amazon | ||
1/4" Tubing | at least 1" | Via Amazon | ||
Filament | at least 350g | Via Adafruit | Will depend on your printer | |
Luer Fitting | 1 | Via Cole Parmer |
Tools:
Name | Notes |
3D Printer | Must have a z-axis of at least 100mm |
Clamps | |
Cup | |
Spoon | |
Scoop | |
Screwdriver | |
Flush Snips |
Materials:
Name | Quantity | Picture | Link | Notes |
Ecoflex 00-30 Silicone | 1 | Via Amazon | ||
Zip-Tie | 2 | Via Amazon | ||
Filament | at least 150g | Via Adafruit | Will depend on your printer | |
1/8" Tubing | 2 lengths of at least 3" | Via Amazon | ||
Luer Fitting | 1 | Via Cole Parmer |
Tools:
Name | Notes |
3D Printer | Must have a z-axis of at least 100mm |
Clamp | |
Cup | |
Spoon | |
Scoop | |
Flush Snips | |
Syringe | An air compressor or squeeze bulb could be used too |
Materials:
Name | Quantity | Picture | Link | Notes |
Arduino Uno | 1 | Via Adafruit | An Arduino Leonardo could also be used here | |
Half-Sized Breadboard | 1 | Via Adafruit | ||
10KΩ Resistor | 3 | Via Adafruit | ||
2.7KΩ Resistor | 2 | Via Amazon | ||
1KΩ Resistor | 1 | Via Amazon | ||
0.1uF Capacitor | 2 | Via Amazon | ||
10uF 50v Electrolytic Capacitor | 2 | Via Amazon | ||
LM358 Dual Op-Amp | 1 | Via SparkFun | Any of the LM358-series chips will work | |
MPS20N0040D-D Pressure Sensor | 1 | Via Amazon | ||
Male-to-Male Jumper Wires | 10 | Via Adafruit |
Name | Quantity | Picture | Link | Notes |
Arduino Micro | 1 | Via Adafruit | ||
Half-sized Perma-Proto Board | 1 | Via Adafruit | ||
10KΩ Resistor | 3 | Via Adafruit | ||
2.7KΩ Resistor | 2 | Via Amazon | ||
1KΩ Resistor | 1 | Via Amazon | ||
0.1uF Capacitor | 2 | Via Amazon | ||
10uF 50v Electrolytic Capacitor | 2 | Via Amazon | ||
LM358 Dual Op-Amp | 1 | Via SparkFun | Any of the LM358-series chips will work | |
MPS20N0040D-D Pressure Sensor | 1 | Via Amazon | ||
22AWG Solid-Core Wire | at least 10" | Via Adafruit | ||
DIP-8 IC Socket | 1 | Via Amazon | ||
Female Headers | 1 | Via Adafruit | ||
Solder | 1 | Via Adafruit |
Tools:
Name | Notes |
Flush Snips | |
Wire Strippers | |
Soldering Iron | |
PCB Vice | Optional, but will come in handy when soldering |
This page will go over the steps to create Design 1 of the PDS.
Begin by printing the .STLs for three-part mold that are found on the Downloads page. Print 1x design1_core.STL and 2x design1_outer.STL. Supports are not necessary for printing.
Assemble the mold with the two outer pieces surrounding the inner core. Put the two clamps around the mold.
Measure out 25ml of Part A and Part B of the Ecoflex 00-30. Put both parts in a cup and mix together thoroughly with a spoon.
Pour the mixed Ecoflex into the mold slowly and steadily and stop occasionally to let bubbles escape. Fill the mold to the brim. Let the silicone cure for 4 hours.
Once the Ecoflex has cured, take the clamps off of the mold and use a screwdriver to pry apart the mold. Pull the cast off of the core.
Attach the lengths of 1/4" and 1/8" tubing with the luer fitting.
Insert the 1/4" end of the tube into the open end of the silicone cast. Secure a zip-around around it and tighten it into place, securing the tubing.
Connect the 1/8" end of the tube to the pressure sensor on the electronics.
Instructions on how to operate Design 1 can be found in the Testing section.
This page will go over the steps to create Design 2 of the PDS.
Begin by printing the .STL of the mold found on the Downloads page. Supports are not necessary for the print.
Measure out 25ml of Part A and Part B of the Ecoflex 00-30. Put both parts in a cup and mix together thoroughly with a spoon.
Pour the mixed Ecoflex into the mold slowly and steadily and stop occasionally to let bubbles escape. Fill the mold to the brim. Let the silicone cure for 4 hours.
Once the Ecoflex has cured, carefully pull the cast out of the mold. Wiggling the cast back and forth helps to remove it.
Follow the Fabrication guide for the PneuNets Bending Actuator up to "Remove main body from molds" in Step 3.
Mix a very small amount of more Ecoflex. Spread a very thin layer (1mm) of it on the flat side of the PDS. Place the cast of the actuator on top of it carefully. Let the silicone cure for 4 hours.
Connect one length of the 1/8" tubing to the Luer fitting. Puncture the end of actuator that is at the same end as the opening of the sensor with a screwdriver. Insert the end of the Luer fitting into the hole. Put one zip-tie around this part of the actuator and the sensor and tighten it only slightly, so that it is held in place. Insert the other length of tubing into the opening of the sensor. Put a zip-tie around this part and tighten.
Connect the tubing from the actuator to the air source (syringe, air compressor, squeeze bulb) and connect the tubing from the sensor to the electronics.
Instructions on how to operate Design 2 can be found in the Testing section.
This page will go over the steps to create the breadboard and the soldered versions of the electronics.
To build the electronics on a breadboard, follow the breadboard diagram and circuit schematic below.
To build the electronics on a soldered Perma-Proto board, follow the breadboard diagram (Perma-Proto boards and breadboards have the same layout) and the circuit schematic.
Remember that the Arduino and the LM358 IC are not soldered directly in. Female headers and DIP sockets are soldered in instead.