Gumband Exhibits
What is an Exhibit?
The Gumband platform is centered around building and maintaining Exhibits, interactive experiences built with a combination of software and hardware components.
Specifically, an Exhibit contains a computer that runs software to orchestrate the user experience. This software is typically a full stack web app with output to one or more screens, but could also just be backend code to control electromechanical I/O.
The following diagrams demonstrate a few ways to build an Exhibit. In each case, the Exhibit developer leverages a Gumband SDK to communicate with the platform and enable various features.
Example exhibit comprised of a computer and multiple Bundles
(Gumband-native microcontrollers) to control external hardware
Example exhibit comprised of a computer and
an Arduino to control external hardware
Example exhibit comprised of a Raspberry Pi
controlling external hardware directly
Exhibit Statuses, Controls, and Settings
Statuses, Controls, and Settings are properties of an Exhibit and can be manipulated by the Exhibit SDK and/or through the Gumband web UI. These items are automatically updated in real time between the Exhibit and Gumband.
Statuses
Statuses are one-way values that are set from the Exhibit SDK and displayed on the web UI. They are used to surface relevant un-editable properties of an Exhibit.
Examples:
Exhibit IP address
Last interaction time or result
Exhibit state
Serial connection status
Controls
Controls are one-way triggers that are fired from the web UI and received in the Exhibit SDK. They are used to execute local code or start some Exhibit functionality.
Examples:
Reload a user interface
Reset an internal counter
Trigger an animation
Run a test sequence
Settings
Settings are key-value pairs that can be updated from either the web UI or Exhibit SDK. They are used to control behavior of the exhibit, both digitally and physically.
Examples:
Third-party API URL (string)
Dev, stage, or production endpoint (dropdown)
Interactive mode (toggle)
Color scheme (hex color)
Inactivity timeout duration (number)
The following diagram shows a simplified view of how Gumband Statuses, Controls, and Settings travel between an Exhibit and the web UI.
Exhibit Manifest
The Exhibit manifest is a JSON file that defines relevant Exhibit information for Gumband, including Statuses, Controls, and Settings. When the Exhibit SDK is initialized, it automatically uploads the manifest and Gumband synchronizes the Exhibit with this list of capabilities.
Exhibit SDK Sidecar
A sidecar application is available that allows projects that use other languages / technologies (Python, C, TouchDesigner, etc) to leverage Gumband functionality. This sidecar runs alongside the main application and the two communicate via Redis or websockets.
Monitoring Exhibit Operating Systems
For Exhibits that have already been developed and cannot integrate the Exhibit SDK, a custom approach using PM2 (https://pm2.keymetrics.io/ ) or Docker (https://www.docker.com/ ) and the Exhibit SDK can be used. This allows for monitoring and high level control (On/Off) for the Exhibit’s computer and running processes.
Gumband Hardware
What is Hardware?
Gumband Hardware, also known as Bundle, is a programmable microcontroller-based platform that is used to control an Exhibit’s electromechanical components. This Hardware has the Gumband stack built in to seamlessly monitor and interact with physical hardware such as buttons, sensors, LEDs, and motors. Bundles also allow for remote firmware updates across a fleet of Hardware.
Types of Hardware
Bundle
The Bundle is Gumband-native hardware for new Exhibit development.
ARM M0+ core handles the entire Gumband communication stack
ARM M4 core is entirely dedicated to user firmware
Program using the Arduino IDE with the Gumband board library
Program natively through Cypress PSoC Creator (advanced)
Two 2x13 0.1” pitch connectors
40 multipurpose GPIO pins
Existing API supports I2C, UART, SPI, Ethernet
Additional protocols (RS485, CAN, LIN, ModBus, etc.) supported by MCU
Gumshoe
For highly-specific functionality, an accessory board called a Gumshoe can be designed and attached to the Bundle, similar to a Pi HAT or Arduino Shield. Gumshoe designs exist for basic breakout capabilities such as screw terminals, high current relays, and stepper drivers. Deeplocal has the capacity to design custom Gumshoe PCBs.
Microcontrollers with Networking
Microcontrollers with networking capabilities can enable Gumband functionality by adhering to a defined MQTT protocol and the Gumband topic hierarchy.
Microcontrollers without Networking
Microcontrollers without networking capabilities can enable Gumband functionality by using Bundle as a passthrough to the platform. To communicate with Bundle, the microcontroller must adhere to a defined low-level protocol over SPI, I2C, or UART.
Custom Microcontrollers
Deeplocal has developed other custom PCB layouts to integrate the Gumband platform into space-constrained mechanical designs and other hyper-specific applications. Deeplocal has the capacity to design custom PCBs and will assess on a case-by-case basis.
Hardware Peripherals and Properties
A Peripheral is a named assembly of physical hardware components within an Exhibit. Each Hardware device will have one or more Peripherals.
Peripherals serve as an organizational structure within which to group Properties. A Property is either an input or output of that Hardware device. Inputs include button state, switch state, dial position, etc and outputs include LED color/brightness, relay state, motor speed, etc. Each physical component within the Peripheral can have one or more Properties.
Peripheral and Property groupings are defined and implemented by the firmware developer.
Example
A motor turns a physical wheel mechanism as part of an Exhibit experience. The Hardware device would have a Peripheral (“Output Crank”) that has two Properties (“Motor Speed” and “Motor Direction”). If necessary, that same Hardware device could control other Peripherals or they could be attached to the Exhibit using additional Hardware.
Using Gumband Hardware
The Bundle Hardware can be breadboarded or mounted on a baseboard known affectionately as a Gumshoe. Mechanical Hardware drawings for mounting purposes and ECAD footprints and specification are available.
Monitoring Gumband Hardware
The Bundle Hardware natively reports its current status upon establishment of a connection to both the Gumband master and the Gumband exhibit. The initial connection handshake includes a manifest of all peripherals and properties of the current exhibit instance in addition to a packet contains status information about the hardware, including: Device ID, Assigned IP, MAC, Gumband Firmware Version, User Firmware Version, Exhibit IP, Exhibit Connection Status, System Voltage and Last Reboot Reason.