Alert System


Alert system for stroke patient, allowing patient to alert their caretaker of any required assistance. The system communicates over TCP/IP, using a client-server architecture. The client, located near the patient, extends a large pushbutton to the patients bed. The server is portable so the caretaker can move it with them, and uses an LED and buzzer as the alert cues. When the patient presses their button, the LED lights and the buzzer activates. The caretaker must clear the alert on their device to acknowledge they have assisted the patient.


  • Raspberry Pi 3 Model B+, w/ 3D Printed Case from thingiverse.
  • (4) #4 x 1/2 flat head screw.
  • Large Momentary Pushbutton Switch, w/ custom 3D Printed Case (thingiverse).
  • Speaker wire & jumper wire.
  • 5V DC Power Adapter.

Client secured under patients bed.

  • Raspberry Pi Zero W, w/ 3D Printed Case from thingiverse.
  • (2) #4 x 3/4 flat head screw.
  • USB Battery Pack.
  • (3) LED (1 Red, 1 Yellow, 1 Green).
  • (2) Momentary Pushbutton Switch.
  • Passive Buzzer.
  • Custom 3D Printed Case (thingiverse).

Server enclosed in casing.

Server alert protoboard.

Server casing CAD drawing.

Technical Details

The project was written in C. The Sockets library was used for TCP/IP communication. The client hardware was a Raspberry Pi 3 Model B+ and the server hardware was a Raspberry Pi Zero W, each running a Linux distribution.

The server creates a socket and binds it to port 6000, then listens for connections. The client creates a socket and attempts to connect to port 6000 of the server's IP address.

An interrupt is attached to the client's pushbutton to alert the server. An interrupt is attached to the server's first pushbutton to clear the alert. An interrupt is attached to the server's second pushbutton to toggle the device's power state (i.e. on/off). A timer is used to trigger the buzzer.

Check It Out

Alert System Demo


The dimensions of the server could be greatly improved by using a smaller battery (i.e. LiPo) with a boost converter. This would allow the designer to remove the space required for the large USB charger and respective cabling, which is a large percentage of the design space.