Introduction: AirStamp - Interactive Stamping

Physical stamping is fun. In this project, we want to turn physical stamping into digital display and allow manipulation of the text being display to make stamping experience different and even more cool such as controlling the text size with hand movement and use blowing to erase the texts. The following page will show you how to make a digital text display using physical stamps as input. Let's begin to build AirStamp!

Co-Designers: Yao Yue Yang, Daisy Zhang, Pang Bo

Step 1: Step 1: Prepare the Materials Required

You will need the following material

Step 2: Step 2: Solder Piezoelectric Meter

Solder the all Piezoelectric Meters to two different colour of wire to differentiate positive and negative as image below.

Solder a resistor to the other end of the two sides of the wire connected to the Piezoelectric Meter. Then solder another 2 pieces of wire on the other end of the resistor as image below.

The end product would be like this.

Solder 5 sets like this. 4 sets would be for the Piezoelectric Meter to detect the pressure of stamping. The last set is to detect air blow pressure.

Step 3: Step 3: Solder Neopixel LED Light

At the back of each Neopixel LED, there are 6 connecting area (labeled below). Connect a wire on each connecting area.

Same as above, connect 4 lights together. Leave the wires on the 2 ends on each side loose to be connected to the Arduino board in Step 4.

Repeat the above. Solder 2 sets of 4 lights which will be placed on each side of the Display Text Box.

Step 4: Step 4: Solder the Arduino Board With the Sensors & Actuators

(1) Prior of soldering the sensors and the LED light to the board, make sure the following are done:

(a) Solder 2 separate sets of 4 LED lights together in Step 3.

(b) Connect the wire came with the IR Distance sensor leaving the loose wire end to be connected to the board.

(c) Solder the Piezoelectric Meter and associate resistors per Step 2


(2) 4x Piezoelectric Meters for detecting the pressure of the stamping, 1x Piezoelectric Meter for detecting air pressure of a blow, 2x IR Distance Sensors and 2 sets of 4 Neopixel LED light each to feedback stamp is detected are all soldered to one Arduino Micro Board while the RFID reader is connected to the same board via USB cable. Place all components like the pictures and schematic below. You can make the board as small as possible. Place all components like the pictures below. You can make the board as small as possible.

(3) RE the order of soldering, we recommend to solder the Piezoelectric Meters to detect the pressure of stamping first at the four corners of the Printed Circuit Board.

(4) Secondly, the RFID Reader USB receiver first to the Printed Circuit Board. RFID Reader's USB has 4 connectors. RX of the USB needs to connect to Arduino's TX while TX of the USB needs to connect to Arduino's RX. The other 2 connectors of the USB needs to connect to VCC and GRD of the Arduino. If your Reader is not reading anything after soldering, you may have the TX and RX reversed or connected wrong.

(5) Then the rest in no particular order. Please reference the length of the wire when you solder. As you can see in the box assembly video, the wire is long because the sensors and LED light would need to run along the box in specific locations so the length is necessary.

Step 5: Step 5: Program RFID Tag

If you choose to buy the reader from another vendor, make sure it comes with a manual. You will need the manual for instruction to write the code to activate the RFID tags specific to the reader so it can be read by the reader automatically when placed onto the reader.

Record the unique identification number of each RFID tag that will be placed to each stamp corresponding to each alphabet. In the Processing code, replace your set of RFID tag ID numbers.

Step 6: Step 6: Code Receiving and Sending Sensors Data From Arduino to Processing

Connect your Arduino Boards to the Computer and run the Arduino and Processing files below. You may need to test the range and sensitivity of the sensors you purchased and adjust the code accordingly to optimize the text display quality.

Processing File: final_processing.zip

Arduino Files: final_2.zip

Including the following

  • Piezoelectric Pressure Meter
  • IR Distance Sensor
  • RFID Sensor LED

Step 7: Step 7: Making the Display and Input Box

(1) The Display and Input Box is laser cut from 3mm MDF. You can use other material that can be laser cut as well such as acrylic. AI files used can be found below. You should result in the following pieces.

(2) The 2 side pieces are painted in black as shown in picture below. Left is before painting while right image is after.

(3) We ran out of paint. Therefore, we stick a piece of black sway cloth to 6 pieces of MDF. We also added 2 pieces of sway that we painted as we found the sway is not as reflective as paint providing better display result.

(4) On the side of the MDF touching the iPad that is not painted/covered by sway, stick 2 pieces of wood with wood glue as shown in picture to hold the iPad Mini in place.

Display & Input Box ai File: box.ai

Acrylic ai File: semi-reflective.ai

Step 8: Step 8: Making the Stamps

We have made 30 stamps including 26 alphabets and 4 symbols. The stamps and the box are laser cut from 3mm MDF. We would recommend 2mm MDF so the stamp is not as big proportional to the RFID reader but we don't have 2 mm MDF available so that's what we used. You can use other material that can be laser cut as well such as acrylic. AI files used can be found below.

The following video illustrated how the stamp is assembled:

We designed a compartment on the stamping end of the stamp as close to the RFID reader as possible. The stamp used joinery design, hence, thinner than 3mm MDF would be less bulky. Use wood glue to glue the edges that are loose after you've programmed the RFID tags. Test your RFID tag and reader sensitivity. The Reader cannot read the smaller tag (i.e. 1mm diameter) with smaller antenna if there's anything in between them thicker than 1mm in our experience. Test them before you proceed with building the stamps.

The box hold all the stamps in one place.

Stamps ai File:stamp8c_2cm_cc.ai

Stamp Box ai File: Stamp_box6_cc.ai

Step 9: Step 9: Assembling Input & Display Box

(1) The assembly of the display and input box is shown in the video below:

(2) Below specify additional details already shown in the video to add clarity. The triangle is placed within the box as shown in the picture below (picture below shown in wood colour to show in picture. It should be covered by black sway) to hold the 2 pieces of acrylic. Make sure the position of the 2 triangle opposite to each other are aligned.

(3) The opening on the top is to fit the RFID Reader. There is an opening on one side for the box for the USB cable. The four Piezoelectric Sensors to be secured at the bottom of the interior of the Input box as image below.

(4) Place a piece of bubble wrap or black sway between the Piezoelectric sensor and the RFID Reader to give some cushion to the Piezoelectric Meters to protect them.

(5) Place a piece of MDF same size as the RFID Reader between the bubble wrap / sway and the RFID Reader.

(6) Finally, place the top piece with the RFID Reader opening to the top. Place a piece of MDF same size to the Reader to the opening to hid the Reader.

(7) Attached the IR Distance Sensor and LED lights to the side pieces of the display box. Repeat for left and right side following the image below.

(8) Place the iPad Mini to the compartment indicated below. The USB cable connecting the computer and iPad should run following the video so the box can be closed.

(9) Finally, place the side pieces to cover the iPad Mini and internal wiring as follow.

Step 10: Step 10: How to Use