Medium⏱ time2.5 hr$ cost26
RFID Access Gate
A card reader opens a servo gate only for the right tag — a model security checkpoint.
Start building ↓
Result first
The build
Step 01
Wire the reader
Connect the RFID module to the Arduino.
Step 02
Store valid IDs
Save approved tag numbers in code.
Step 03
Control the gate
Servo opens on a match, stays shut otherwise.
Step 04
Test access
Tap tags — valid ones open the gate.
Working Principle
The reader reads each tag's unique ID; the code checks it against an approved list and opens the gate only on a match.
The science behind it
A closer look
It's authentication by identifier — the same idea as door fobs and transit cards, minus the encryption.
Take it further
Variables to test
- 1 Add a second valid tag.
- 2 Log how many denied attempts occur.
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