viam.components.encoder.encoder

Classes

Encoder

Base component.

Module Contents

class viam.components.encoder.encoder.Encoder(name: str, *, logger: logging.Logger | None = None)[source]

Bases: viam.components.component_base.ComponentBase

Base component. All components must inherit from this class.

class Properties[source]
ticks_count_supported: bool
angle_degrees_supported: bool
SUBTYPE: Final

The Subtype of the Resource

abstract reset_position(*, extra: Dict[str, Any] | None = None, timeout: float | None = None, **kwargs)[source]
Async:

Set the current position to be the new zero (home) position.

my_encoder = Encoder.from_robot(robot=machine, name='my_encoder')

# Reset the zero position of the encoder.
await my_encoder.reset_position()

For more information, see Encoder component.

abstract get_position(position_type: viam.proto.component.encoder.PositionType.ValueType | None = None, *, extra: Dict[str, Any] | None = None, timeout: float | None = None, **kwargs) Tuple[float, viam.proto.component.encoder.PositionType.ValueType][source]
Async:

Report the position of the encoder. The value returned is the current position in terms of it’s position_type. The position will be either in relative units (ticks away from a zero position) for PositionType.POSITION_TYPE_TICKS_COUNT or absolute units (degrees along a circle) for PositionType.POSITION_TYPE_ANGLE_DEGREES.

my_encoder = Encoder.from_robot(robot=machine, name='my_encoder')

# Get the position of the encoder in ticks
position = await my_encoder.get_position(PositionType.POSITION_TYPE_TICKS_COUNT)
print("The encoder position is currently ", position[0], position[1])
Parameters:

position_type (PositionType) – The desired output type of the position.

Returns:

A tuple containing two values; the first [0] the position of the encoder which can either be ticks since last zeroing for a relative encoder or degrees for an absolute encoder, and the second [1] the type of position the encoder returns (ticks or degrees).

Return type:

Tuple[float, PositionType]

For more information, see Encoder component.

abstract get_properties(*, extra: Dict[str, Any] | None = None, timeout: float | None = None, **kwargs) Properties[source]
Async:

Return a dictionary of the types of position reporting this encoder supports.

my_encoder = Encoder.from_robot(robot=machine, name='my_encoder')

# Get whether the encoder returns position in ticks or degrees.
properties = await my_encoder.get_properties()
Returns:

Map of position types to supported status.

Return type:

Encoder.Properties

For more information, see Encoder component.

classmethod from_robot(robot: viam.robot.client.RobotClient, name: str) typing_extensions.Self

Get the component named name from the provided robot.

Parameters:
  • robot (RobotClient) – The robot

  • name (str) – The name of the component

Returns:

The component, if it exists on the robot

Return type:

Self

abstract do_command(command: Mapping[str, ValueTypes], *, timeout: float | None = None, **kwargs) Mapping[str, ValueTypes]
Async:

Send/Receive arbitrary commands to the Resource

command = {"cmd": "test", "data1": 500}
result = await component.do_command(command)
Parameters:

command (Mapping[str, ValueTypes]) – The command to execute

Raises:

NotImplementedError – Raised if the Resource does not support arbitrary commands

Returns:

Result of the executed command

Return type:

Mapping[str, ValueTypes]

async get_geometries(*, extra: Dict[str, Any] | None = None, timeout: float | None = None) List[viam.proto.common.Geometry]

Get all geometries associated with the component, in their current configuration, in the frame of the component.

geometries = await component.get_geometries()

if geometries:
    # Get the center of the first geometry
    print(f"Pose of the first geometry's centerpoint: {geometries[0].center}")
Returns:

The geometries associated with the Component.

Return type:

List[Geometry]

classmethod get_resource_name(name: str) viam.proto.common.ResourceName

Get the ResourceName for this Resource with the given name

# Can be used with any resource, using an arm as an example
my_arm_name = Arm.get_resource_name("my_arm")
Parameters:

name (str) – The name of the Resource

Returns:

The ResourceName of this Resource

Return type:

ResourceName

get_operation(kwargs: Mapping[str, Any]) viam.operations.Operation

Get the Operation associated with the currently running function.

When writing custom resources, you should get the Operation by calling this function and check to see if it’s cancelled. If the Operation is cancelled, then you can perform any necessary (terminating long running tasks, cleaning up connections, etc. ).

Parameters:

kwargs (Mapping[str, Any]) – The kwargs object containing the operation

Returns:

The operation associated with this function

Return type:

viam.operations.Operation

async close()

Safely shut down the resource and prevent further use.

Close must be idempotent. Later configuration may allow a resource to be “open” again. If a resource does not want or need a close function, it is assumed that the resource does not need to return errors when future non-Close methods are called.

await component.close()