Wireless Wall Dock for Guition 3.5 display

Wireless Docking Home Assistant Wall Controller (Guition 3.5")

Overview

This project is a fully portable ESPHome-powered Home Assistant wall controller built around the Guition 3.5" ESP32-S3 capacitive touchscreen.

Unlike traditional wall-mounted control panels, this one can simply be lifted from its magnetic wall dock and continues operating from its internal rechargeable battery. When placed back onto the dock, it automatically recharges through wireless Qi charging, eliminating exposed charging contacts and providing a clean, seamless appearance.

The goal of this project was to create a smart home controller that looks like a permanently installed wall panel while remaining completely portable whenever needed.

The project includes the complete enclosure, magnetic wall dock and all required mounting parts. The user interface shown in the photos is built with ESPHome + LVGL and can be fully customized to suit your own Home Assistant installation.

Features

• 3.5" capacitive touchscreen
• ESP32-S3 running ESPHome
• Home Assistant integration
• Portable operation with built-in rechargeable battery
• Magnetic wall docking station
• Support both portrait and landscape installation
• Automatic wireless Qi charging
• Single screw enclosure assembly
• Fully customizable LVGL interface

Integrated Sensors

The controller includes several sensors to make it behave intelligently without requiring user interaction.

LD2410 Human Presence Sensor

The LD2410 detects when someone is standing in front of the controller and automatically wakes the display.

VEML7700 Ambient Light Sensor

The display brightness automatically adjusts according to the surrounding light conditions.

MPU6050 Accelerometer & Gyroscope

If the controller is picked up from the wall or simply moved, the display automatically wakes even when no presence is detected.

The MPU6050 is also used to detect the controller's orientation. This makes it possible to automatically rotate the user interface or display different pages depending on whether the controller is held in portrait or landscape orientation.

The internal temperature sensor of the MPU6050 is also used to monitor the controller's internal temperature.

Additional Monitoring

The controller also measures:

• Battery voltage
• Battery level
• WiFi signal strength
• Internal device temperature

Audio

A miniature speaker is connected directly to the ESP32.

It provides audible feedback for every button press and is also exposed to Home Assistant as a Media Player.

This allows the controller to play:

• TTS announcements
• Notification sounds
• Doorbell sounds
• Any other audio supported by ESPHome

Smart Power Management

To maximize battery life and reduce display wear, several automatic power-saving functions are implemented.

The controller automatically adjusts the display brightness according to the ambient light measured by the VEML7700.

The display wakes automatically when:

• someone approaches the controller (LD2410)
• the controller is picked up or moved (MPU6050)

When the controller becomes idle, the backlight turns off while an anti burn-in routine periodically moves the screen contents to protect the display.

Wireless Docking System

The wall dock contains:

• Qi wireless charging transmitter
• 4pcs 6×4 mm neodymium magnets

The controller contains:

• Qi wireless charging receiver
• 4pcs 6×4 mm neodymium magnets
• Internal rechargeable Li-Ion battery

The magnets automatically align the Qi charging coils, ensuring reliable charging every time the controller is placed on the dock.

There are no exposed charging contacts to wear out or become dirty.

Mechanical Design

The enclosure was designed to be simple to assemble while keeping the exterior clean and minimizing the number of fasteners.

Features include:

- only one M3 screw holds the entire enclosure together
- captive M3 hex nut
- slide-in Qi receiver (no glue required)
- press-fit Qi transmitter in the wall dock (no glue required)
- integrated battery compartment
- hidden wiring
- removable front assembly

The Li-Ion battery is permanently embedded inside the rear cover during printing using a Pause at Height command. After inserting the battery, printing resumes and the remaining layers create three retaining tabs that securely hold it in place without requiring a separate battery holder.

Both the wall dock and the controller use four 6×4 mm neodymium magnets. The magnets should be glued into their dedicated pockets using CA glue or epoxy. Besides securely holding the controller in place, they also ensure accurate alignment of the Qi charging coils for reliable wireless charging every time the controller is docked.

The Qi transmitter module PCB is designed as a press-fit component. It fits tightly into the wall dock and does not require any glue or additional fasteners.

The enclosure wall in front of the VEML7700 ambient light sensor is intentionally made thinner than the rest of the enclosure. This allows more ambient light to reach the sensor, improving the accuracy and responsiveness of the automatic brightness control while keeping the sensor completely hidden from view.

The wall dock is designed to support both portrait and landscape installation. The mounting slots allow for fine adjustment during installation, making it easy to perfectly level the dock before tightening the mounting screws.

Electrical Design

The Guition display uses 1.25 mm JST connectors, so a few additional cables are required to connect the external modules.

Two 2-pin connectors are needed for the speaker and the Li-Ion battery. The speaker does not include a connector, while the battery comes with a different connector type, so its original connector must be replaced.

The VEML7700 ambient light sensor and the MPU6050 IMU are connected via the I²C bus using a 4-pin connector.

The LD2410 presence sensor communicates over UART and connects using an 8-pin connector.

The LD2410 requires a 5V power supply, while the Guition board provides a regulated 3.3V output for external modules. To power the LD2410 both when the controller is docked and when it is running from its internal battery, a compact 5V boost converter is used to step the regulated 3.3V supply up to 5V.

Printing Notes

Due to the heat generated by the Qi receiver during charging, PLA is not recommended.

Recommended materials:

• PETG
• ASA
• ABS

The battery embedding process requires a Pause at Height command during printing.

Software

The controller runs entirely on ESPHome and integrates seamlessly with Home Assistant.

The interface shown in the photos is only an example.

Since everything is based on ESPHome and LVGL, you can freely modify the layout, pages, icons, widgets and functionality to fit your own smart home.

Bill of Materials

• 1pcs Guition 3.5" ESP32-S3 display (https://www.aliexpress.com/item/1005007566332450.html)
• 1pcs LD2410 presence sensor (https://www.aliexpress.com/item/1005009477395792.html)
• 1pcs VEML7700 light sensor (https://www.aliexpress.com/item/1005009958037220.html)
• 1pcs MPU6050 IMU (https://www.aliexpress.com/item/1005009301512511.html)
• 1pcs Qi wireless charging transmitter (https://www.aliexpress.com/item/1005008926853599.html)
• 1pcs Qi wireless charging receiver with TYPE-C (https://www.aliexpress.com/item/1005008190654562.html)
• 1pcs 103450 Li-Ion battery (https://www.aliexpress.com/item/1005011644288901.html)
• 1pcs “1609” mini speaker (https://www.aliexpress.com/item/1005009962950710.html)
• 1pcs 5V mini boost converter (https://www.aliexpress.com/item/1005005624977910.html)
• 1pcs 230VAC/5VDC/10W power supply (https://www.aliexpress.com/item/1005007235244555.html)
• 8pcs 6x4mm neodymium magnets (https://www.aliexpress.com/item/1005009489365038.html)
• 1pcs M3 hexnut (https://www.aliexpress.com/item/1005006165793439.html)
• 1pcs M3 10mm countersunk flat head screw (https://www.aliexpress.com/item/1005007156195899.html)
• 2pcs 1.25mm 2pin wire cable connector (https://www.aliexpress.com/item/1005007277110532.html)
• 1pcs 1.25mm 4pin wire cable connector (https://www.aliexpress.com/item/1005007277110532.html)
• 1pcs 1.25mm 8pin wire cable connector (https://www.aliexpress.com/item/1005007277110532.html)