Kinetic Display

The Kinetic Display is an innovative and engaging way to showcase the current time, date, indoor temperature and humidity, and outdoor temperature and humidity. This robotic seven-segment clock-like display consists of 4 digits and 2 colons, totaling 30 actuators that extend and retract segments. Each segment lights up when extended and turns off when retracted, creating a satisfying clacking sound with every movement, adding a unique auditory experience. The user guides details all the Kinetic Display features and settings:

1. Orientation - Kinetic Display
2. On/Off Switch - Kinetic Display
3. Web Service Settings - Kinetic Display
4. Schedule Creation and Management - Kinetic Display

Designed for durability, the display is built to last for years when assembled correctly by following the easy to read documentation at https://gobbyo.github.io/kinetic-display/. Also, be sure to visit the page https://gobbyo.github.io/kinetic-display/intro/ for a brief overview and video of the features, the experiments involved in designing the display, and the first prototype running since April 2024.

Clone a fork of files you'll need at kinetic-display GitHub.

1. Bill of Materials - Kinetic Display
2. Order PCBs - Kinetic Display
3. Print Parts - Kinetic Display

Tools

1. 3D printer
2. Wire Stripper for 28 AWG stranded wire
3. Small Philips head screwdriver
4. Dupont connector tool
5. Soldering station with solder/flux
6. Needle nose pliers
7. Tweezers
8. Clamping tweezers
9. Zinc strip or thin metal strip (for melting PLA)
10. Wire snipper
11. Multimeter
12. Breadboard and jumpers for testing electronics
13. Label maker (optional)
14. Computer with USB connector

The picture shows what occurs when the prerequisite software is installed, your Raspberry Pi Pico has been flashed, and a connection established between (A) your computer and (B) the Raspberry Pi Pico.

Be sure to complete the prerequisite instructions at Install Prerequisite Software - Kinetic Display

There are 30 actuators in the display, 7 per digit and 2 for the colons (4 digits x 7 segments + 2 colons = 30 total actuators). The actuator assembly includes installing the shaft gear onto the DC brushed motor, preparing and adding wires to the motor, assembling the motor mount, pinion gear, and shaft, then adding the DC brushed motor to the assembled motor mount.

The picture shows a fully assembled actuator.

Follow the guide to Build the Actuators at Actuators - Kinetic Display

The display has 4 digits, numbered from right to left (0-3) when viewed from the front. The digit PCBs are for digits 0, 2, and 3, while the controller PCB (digit 1) includes the colons. The digit PCBs are the foundation of the display and serve several important functions:

1. Mechanical Backstop: Provides a sturdy backstop for the actuator's segment when retracting into the display.
2. Uniform Lighting: Ensures consistent light dispersion for each segment, creating a uniform glow without hotspots.
3. Efficient Circuitry: Reduces wiring complexity, connects components efficiently, and ensures reliable, cost-effective, and consistent quality.

The picture shows the front face of fully assembled PCBs.

Follow the guide to Assemble the Digit PCBs at Digit PCBs - Kinetic Display.

In this guide you will upload code from the digit folder on your computer to your Raspberry Pi Pico 2040.

The picture shows how to upload the digit project to the Raspberry Pi Pico 2040.

Follow the guide to Deploy the Digit Project to the Digit PCBs at Deploy Digit Project - Kinetic Display.

Run the tests in this guide after assembling each digit PCB to ensure all components are soldered correctly and functional. Any defective electronic component on the digit PCB must be replaced before completing the project.

The picture shows connecting the actuator to the digit PCB, plugging in your computer's USB connector into the Raspberry Pi Pico 2040, and running the tests.

Follow the guide to Test the Digit PCBs at Digit PCB Test - Kinetic Display

Digit 1 and the colons are on a single PCB. Digit 1, powered by a Raspberry Pi Pico 2040, is identical to digits 0, 2, and 3 except it is contained on a single PCB with the conductor. The Raspberry Pi Pico W 2040 (conductor) operates the colons and serves as the central command and control for the display, performing the following functions:

1. Sends commands to digits as to what to display (e.g., 0-9, A-F).
2. Sends commands for the brightness of the digits.
3. When in Admin mode, transmits its own Wi-Fi service to wirelessly change the display settings from a cell phone or computer.
4. Manages the scheduler, which is the mechanism for displaying time, date, external temperature and humidity, and interior temperature and humidity.
5. When connected to a Wi-Fi network, obtains its public-facing IP address, looks up the time zone it is located in, and sets the display to the local time.
6. When connected to a Wi-Fi network, obtains the closest weather station and, depending on the scheduler, may display the external temperature and humidity.
7. Manages the low power consumption mode by turning off the power to digits 0-3. When awakened, it turns on the power to digits 0-3.

The picture shows the front face of the Conductor and Digit 1 PCB fully assembled.

Follow the guide to Assemble the Conductor and Digit 1 PCB at Conductor PCB - Kinetic Display.

In this guide you will upload code from the conductor folder on your computer to your Raspberry Pi Pico W 2040.

The picture shows how the conductor code project is uploaded to the conductor.

Follow the guide to Deploy the Conductor Project to the Conductor PCB at Deploy Conductor Project - Kinetic Display

Run the tests in this section after assembling the conductor PCB to ensure all the components on the PCB are soldered and functional. Any defective electronic component on the conductor PCB will need to be replaced before completing the project.

The picture shows the actuator connected to the Conductor PCB and your computer's USB plugged into the Raspberry Pi Pico W.

Follow the guide to test the Conductor PCB at Conductor PCB Test - Kinetic Display

There are several choices of power supplies available in the market. Why not simply use a retail 5V power supply? A few important reasons for building a custom power management system for the display include:

1. Stable Voltage: A drop in voltage occurs in a poor power supply when the heavy-duty 103 electric toy motor starts up because each motor requires a high inrush of current to extend or retract the display's segments. Most retail power supplies cannot provide sufficient current, causing a dramatic voltage drop leading to instability. The power supply setup in this section ensures the components receive a consistent 5V power, preventing malfunctions or damage to the more sensitive electronic components like the microcontrollers and sensors.
2. Current Requirements: The display has colons with two motors and four digits, each with seven independent electric motors. There can be up to five electric motors running simultaneously to extend or contract the segments or colons. Note there are also additional power requirements for lighting the LEDs. The power system you'll build in this section provides sufficient current to power all motors, sensors, and controllers simultaneously.
3. Safety: Protects the system from overvoltage, short circuits, or power surges.
4. Customization: Tailors the power supply to meet the specific needs of the kinetic display's design and components.
5. Efficiency: Reduces energy loss and improves the overall performance of the display. An old-school coil-driven relay is used to shut off power to the digits when in low-power mode and not active. There are other ways to accomplish the same functionality with solid-state relays or a FET. However, the display is kinetic by design, and the use of a coil relay enhances its sound, feel, and aesthetics.

The picture shows the fully assembled power management PCB.

Follow the guide to Assemble the Power Management PCB at Power Management PCB - Kinetic Display

Run the tests in this guide after assembling the power management PCB. Any defective electronic component on the power management PCB will need to be replaced before completing the project.

The picture shows the Raspberry Pi Pico W connected to the Songle relay and plugged into your computer's USB cable.

Follow the guide to Test the Power Management PCB at Power Management PCB Test - Kinetic Display

Buck converters are essential for converting 12V DC to 5V DC because they efficiently step down the voltage while minimizing energy loss. Unlike linear regulators, which dissipate excess voltage as heat, buck converters use high-frequency switching and inductors to transfer energy more efficiently. This makes them ideal for powering sensitive electronics like micro controllers and LEDs, as they provide stable output voltage, reduce heat generation, and improve overall system reliability.

This guide provides detailed instructions for assembling and wiring DC to DC variable buck converter modules in a Kinetic Display system. It includes a list of required components and tools, step-by-step guidance for wiring and securing the modules, and calibration instructions to ensure proper voltage output.

1. Correct Wiring: Proper routing and connection of wires are critical to ensure the display functions correctly. Incorrect wire lengths or connections can lead to assembly issues or electrical faults.
2. Voltage Calibration: The buck converters step down the input voltage from 12V to a stable 5.0-5.1V output. Calibration ensures the modules provide the correct voltage to prevent damage to connected components or malfunctions.
3. Safety Measures: Follow anti-static precautions and use proper tools to avoid damaging sensitive electronics during assembly.

The picture shows the Buck Modules wired and connected to each PCB.

Follow the Buck Module wiring guide to ensure the reliability and safety of the Kinetic Display system at Buck Module Wiring - Kinetic Display

UART (Universal Asynchronous Receiver-Transmitter) facilitates communication between the conductor and the digit PCBs. The conductor acts as the central hub, transmitting commands and receiving status updates from the digits.

1. Conductor (Transmitter and Receiver):
2. The conductor's UART Tx (transmit) pin sends data to the digits, such as display commands and brightness levels.
3. The conductor's UART Rx (receive) pin listens for acknowledgment or status updates from the digits.
4. Digits (Receivers and Transmitters):
5. Each digit PCB's UART Rx pin receives commands from the conductor.
6. The digit PCBs' UART Tx pins send status updates or responses back to the conductor.

This bidirectional communication ensures synchronized operation of the display, enabling the conductor to manage all digits effectively.

The picture shows the completed UART wiring (blue and yellow) and Relay wire (orange).

Follow the guide to wire the UART and Relay connections at UART and Relay Wiring - Kinetic Display

This guide details assembling the PCBs onto the display face and includes integration testing of the electronic components that make the Kinetic Display function.

Following the picture:

1. (A) Connect the DHT22 sensor to the conductor PCB.
2. (B) Plug in the 12V power supply into the power management PCB's barrel jack. Note: The DHT22 sensor connection is temporary and will be permanently installed later.
3. (C) Connect your computer's USB cable to the conductor PCB Raspberry Pi Pico W 2040.

Then run the integration tests.

Follow the guide to assemble the display face and PCBs then integration test it at Display Face and PCBs Assembly with Integration Testing - Kinetic Display

This guide details installing the backplate onto the display face, installing the DHT22 sensor, connecting the motor wires to the motor pins, and installing the stand and power manager onto the display face. Below is the back of the display when the backplates and stand are assembled.

There is a short-form and long-form stand. The picture shows the installation of the long-form stand.

Follow the guide to assemble the backplates and stand at Backplate and Stand Assembly - Kinetic Display

The digit segments and colons give the display its distinctive design. Each hollow segment lights up when extended and turns off when retracted, creating a satisfying clacking sound with every movement. Like a traditional seven-segment display, the segments are tilted at a 5-degree angle for a sleek appearance.

The picture shows the 3D printed parts needed to complete the assembly of the display.

Follow the guide to assemble and install the segments onto the display at Segment Assembly and Installation - Kinetic Display

This guide shows you where to install the QR codes that provide a quick link to the display's network Wi Fi access point and web service.

The picture shows the two locations where they are installed.

Follow the guide to complete the assembly of your display with a few finishing touches at Finishing Touch - Kinetic Display. Once you've completed the finishing touches you'll need to follow the guide to configure you display at Web Service Settings - Kinetic Display.