Medical Chair Controller
Custom electronic control circuit for a medical chair — motor-driven positioning with LCD display, push-button interface, and multi-channel actuator outputs
Project Overview
Designed a custom electronic control circuit for a motorized medical chair, enabling precise position control of chair movements (recline, elevation, tilt) through a simple push-button interface with real-time status displayed on a 20×4 LCD screen.
Front view showing the 20×4 LCD display, motor driver IC, DC-DC converter, push-button interface, and labeled screw terminal outputs (left). PCB bottom view showing clean trace routing and solder joints (right).
Key Features
- 20×4 LCD Display — real-time status feedback and position indication
- Multi-Channel Motor Outputs — 16 labeled output terminals driving chair actuators (recline, lift, tilt)
- Push-Button Interface — 4 tactile buttons for intuitive chair position control
- DC-DC Buck Converter — on-board regulated power supply for logic and motor drive
- Motor Driver IC — DIP package driver IC for multi-directional motor control
- Screw Terminal Outputs — secure connections to chair actuators and external systems
- Compact Single-Board Design — controller and display integrated on one PCB stack
Hardware Architecture
| Block | Implementation |
|---|---|
| Display | 20×4 character LCD (204ZPA) with blue backlight |
| MCU | Microcontroller managing button input, display, and output logic |
| Motor Drive | DIP motor driver IC — bi-directional actuator control |
| Power | DC-DC buck converter — regulated rail for all subsystems |
| User Input | 4 push buttons for position commands |
| Outputs | 16-channel screw terminal bank for actuator wiring |
Technologies & Tools
- PCB design — schematic capture and custom layout
- Embedded C / Arduino — firmware for motor sequencing and LCD control
- DC-DC power supply design
- Motor driver and actuator interfacing
Key Achievements
✅ Designed a complete motor control solution for a medical chair
✅ Integrated 20×4 LCD for real-time position and status feedback
✅ 16-channel output bank supporting multiple independent actuators
✅ Compact single-board design combining control, display, and power