AMT Encoder
AMT Encoder usually refers to the AMT series of rotary encoders made by CUI Devices / Same Sky.
These are used in robotics, CNC machines, motors, and automation systems to measure:
- Shaft position
- Rotation speed
- Direction
- Angular displacement
The AMT series is known for using capacitive sensing technology instead of traditional optical sensing.
What Makes AMT Encoders Special?
1. Capacitive Sensing
Unlike optical encoders, AMT encoders are:
- Resistant to dust, oil, and dirt
- More rugged in industrial environments
- Less sensitive to vibration
2. High Precision
They can provide very fine rotational measurements:
- Incremental outputs (A/B quadrature)
- Absolute position outputs
- Multi-turn tracking in some models
3. Programmable Resolution
Some AMT encoders allow configurable resolutions like:
- 48 PPR
- 1024 PPR
- 4096 PPR
Common AMT Encoder Types
| Type | Example | Purpose |
|---|---|---|
| Incremental Encoder | AMT10, AMT11, AMT12 | Measures relative movement |
| Absolute Encoder | AMT21, AMT22 | Gives exact shaft angle immediately after power-up |
| Commutation Encoder | AMT31, AMT33 | Used for BLDC motor commutation |
Example: Incremental AMT Encoder
An incremental AMT encoder outputs pulses as the shaft rotates.
If:
- Encoder = 1000 PPR
- Motor makes 1 revolution
Then the controller receives:
- 1000 pulses (or 4000 counts using quadrature)
Used for:
- PID speed control
- Odometry
- Servo feedback
- Robotics
Example: Absolute AMT Encoder
Absolute encoders know the shaft’s exact angle even after power loss.
Example:
- Shaft at 237°
- Power off
- Power on
- Encoder still reports 237°
Useful for:
- Robotic arms
- CNC axes
- Elevators
- Positioning systems
AMT21/22 models support multi-turn tracking too.
Typical Signals / Output
Depending on model:
- Quadrature A/B
- PWM
- SPI
- SSI
- RS-485
- U/V/W commutation signals
Applications
AMT encoders are commonly used in:
- Robotics
- BLDC motors
- Servo systems
- CNC machines
- Industrial automation
- AGVs and autonomous robots
It tells the controller:
- How far the motor turned
- How fast it’s spinning
- Which direction it moved
Additional Topics You Can Explore
- Incremental vs Absolute Encoders
- How AMT Encoders Work Internally
- Wiring Diagrams
- Arduino / ESP32 Interfacing
- Reading Encoder Signals in Code
- AMT vs Magnetic vs Optical Encoders