A key part to researching tactile interfaces is the hardware. This section describes what we have built. This list is in reverse chronological order.
This is the latest electronics board revision. Similar to v0.4 but with few electronic bug fixes. This design is still in manufacturing and testing.
This design has been demonstrated and discussed in the UIST publication, as Vibrotactile Haptics Platform (VHP).
This is wearable watch-band like device with 8 tactors. Compared to our earlier "sleeve" form factors, the idea here is that a band is more convenient to put on and wear.
The pdf of the schematic can be found here. The design was done in Altium Designer. The design files are located in slim_bracelet_design/pcb.
Use the firmware programming guide to see different options for programming the embedded microcontroller. The programming is simplified by using Arduino IDE.
The mechanical design was done using Fusion 360, and parts were printed on Prusa i3 MK3S+. The mechanical design files for the bracelet can be found in slim_bracelet_design/enclosure_parts.
The steps to put the bracelet together are described in this guide.
Wearable sleeve-like device with 10 tactors. In this design, the electronics are split into separate "puck" and "sleeve" modules, connected by a cable. The puck contains the mic and battery, and the sleeve has the tactor array worn on the forearm. For fit, the tactors are mounted on a flexible 3D-printed mesh and wired using a flex PCB.
Wearable sleeve-like device with 10 tactors. It has a microphone, an nRF52 microcontroller for light signal processing, and an array of 10 tactors. The device has a custom PCB, capable of driving up to 12 tactors. To improve the fit, the device body is articulated with hinge joints to conform to the geometry of the wearer's arm.
Circuit diagram (the right half from PWM output onward is repeated six times for up to 12 tactors):
As an early non-mobile prototype, we connected a sleeve of 24 tactors to a Motu audio interface. We also used this hardware to test the TAPS phonemic code system.
The sleeve body is constructed from cloth and Velcro. The tactors are Tectonic TEAX13C02-8/RH speakers with vinyl bumpers glued to them. It is connected by two ribbon cables to a Motu 24Ao audio interface device, which connects by USB to a computer producing tactile signals. The Motu has three DB25 D-Sub connectors, each with eight channels. We use twelve MAX98306 Stereo Amplifier boards for amplification.
A simple stereo amplifier circuit with a MAX98306 Stereo Amplifier board and a 3.5mm stereo plug makes it possible to drive two tactors with the audio output from a computer. This is useful for small experiments.
As above, the tactors are Tectonic TEAX13C02-8/RH speakers with vinyl bumpers glued to them.
