# Add a component

Every component on your machine has a **type** that determines its API, which defines what methods your code can call on it. Pick the type whose API best describes what your hardware does, then use the per-type guide to add a model and configure it. The general add-a-component process is the same for every type. For the universal steps, see [Configure hardware components](https://docs.viam.com/hardware/configure-hardware/).

The **Features** column lists platform integrations the type is part of. Every type supports `DoCommand` and shows a test panel on its configuration card, so those aren’t repeated in the column; exceptions are called out where they apply. **Data capture** means the built-in data manager can capture this type’s output to the Viam cloud. **Readings** means the type returns a flat key-value snapshot through the `GetReadings` method, on top of its type-specific API.

## Control an arm, gripper, or gantry

| Component | What it does | Examples | Features |
| --- | --- | --- | --- |
| [Arm](https://docs.viam.com/hardware/common-components/add-an-arm/) | Control a multi-joint robotic arm: move joints, position the end effector, integrate with motion planning. | xArm, UR5, custom serial arms | — |
| [Gripper](https://docs.viam.com/hardware/common-components/add-a-gripper/) | Open, close, and grasp objects with a gripper mounted on an arm or gantry. | Parallel-jaw grippers, vacuum grippers | — |
| [Gantry](https://docs.viam.com/hardware/common-components/add-a-gantry/) | Move a tool head, camera, or sensor to precise coordinates along one or more linear axes. | Single-axis stages, multi-axis CNC gantries | — |

## Sensing

Components that read data from the physical world.

| Component | What it does | Examples | Features |
| --- | --- | --- | --- |
| [Camera](https://docs.viam.com/hardware/common-components/add-a-camera/) | Capture images or video from a USB webcam, IP camera, or depth sensor. | USB webcams, IP cameras, depth cameras, lidar | Data capture |
| [Sensor](https://docs.viam.com/hardware/common-components/add-a-sensor/) | Read environmental data: temperature, humidity, distance, air quality, and more. | Temperature, humidity, air quality, distance sensors | Data capture · Readings |
| [Movement sensor](https://docs.viam.com/hardware/common-components/add-a-movement-sensor/) | Get position, velocity, orientation, or compass heading from a GPS, IMU, or odometry source. | GPS, IMU, accelerometer, gyroscope, odometry | Data capture · Readings |
| [Power sensor](https://docs.viam.com/hardware/common-components/add-a-power-sensor/) | Monitor voltage, current, and power consumption. | INA219, INA226, current clamps | Data capture · Readings |
| [Encoder](https://docs.viam.com/hardware/common-components/add-an-encoder/) | Track how far a motor has turned and how fast it’s spinning. | Incremental encoders, absolute encoders | Data capture |
| [Audio input](https://docs.viam.com/reference/apis/components/audio-in/) | Stream audio from a microphone or audio-in device. | USB microphones, Pi audio-in HATs | Data capture · No test panel |

## Drive a mobile robot

| Component | What it does | Examples | Features |
| --- | --- | --- | --- |
| [Base](https://docs.viam.com/hardware/common-components/add-a-base/) | Drive a mobile robot with movement commands like “move forward 300mm” or “spin 90 degrees.” A base wraps your drive system into a single interface. | Wheeled rovers, tracked vehicles, holonomic platforms | — |

## Control motors and servos

| Component | What it does | Examples | Features |
| --- | --- | --- | --- |
| [Motor](https://docs.viam.com/hardware/common-components/add-a-motor/) | Control a DC or stepper motor through a motor driver and GPIO pins. | DC motors, stepper motors, brushless motors | Data capture |
| [Servo](https://docs.viam.com/hardware/common-components/add-a-servo/) | Set the angular position of a hobby servo with a PWM pin. | Hobby servos, PWM-controlled actuators | — |

## Inputs and GPIO

Components for physical I/O and user input.

| Component | What it does | Examples | Features |
| --- | --- | --- | --- |
| [Board](https://docs.viam.com/hardware/common-components/add-a-board/) | Expose GPIO pins, analog readers, and digital interrupts from a single-board computer. Many other components depend on a board. | Raspberry Pi GPIO, ESP32, PCA9685 IO expander | — |
| [Button](https://docs.viam.com/hardware/common-components/add-a-button/) | Detect presses from a physical button to trigger actions. | Momentary switches, push buttons | — |
| [Switch](https://docs.viam.com/hardware/common-components/add-a-switch/) | Read or set the position of a toggle or selector switch. | Toggle switches, selector switches | — |
| [Input controller](https://docs.viam.com/hardware/common-components/add-an-input-controller/) | Use a gamepad, joystick, or other input device for manual machine control. | Gamepads, joysticks, custom button panels | — |

## Other

| Component | What it does | Examples | Features |
| --- | --- | --- | --- |
| [Generic](https://docs.viam.com/hardware/common-components/add-a-generic/) | Interface with hardware that doesn’t fit any standard component type. | Custom devices with non-standard interfaces | — |
| [Audio output](https://docs.viam.com/reference/apis/components/audio-out/) | Play audio on a speaker or audio-out device. | USB speakers, audio-out HATs | No test panel |

## Choosing a type

Match your hardware to the type whose API best describes what it does:

- If it **produces images**, use [camera](https://docs.viam.com/hardware/common-components/add-a-camera/).
- If it **produces readings** (temperature, distance, pressure), use [sensor](https://docs.viam.com/hardware/common-components/add-a-sensor/).
- If it **reports position or motion** (GPS, IMU), use [movement sensor](https://docs.viam.com/hardware/common-components/add-a-movement-sensor/).
- If it **spins or drives linear motion**, use [motor](https://docs.viam.com/hardware/common-components/add-a-motor/).
- If it **moves to an angle**, use [servo](https://docs.viam.com/hardware/common-components/add-a-servo/).
- If you need **direct GPIO access**, use [board](https://docs.viam.com/hardware/common-components/add-a-board/).
- If **nothing fits**, use [generic](https://docs.viam.com/hardware/common-components/add-a-generic/). It provides `DoCommand` for arbitrary interactions.

Every type also has a `DoCommand` method for functionality beyond the standard API. For example, a sensor that also has a calibration routine can expose calibration through `DoCommand` while still using `GetReadings` for its primary data.