encoder

Documentation

Overview

Package encoder implements the encoder component

Index

• Constants
• Variables
• func Named(name string) resource.Name
• func NamesFromRobot(r robot.Robot) []string
• func NewEncodedMotorPositionTypeUnsupportedError(props Properties) error
• func NewPositionTypeUnsupportedError(positionType PositionType) error
• func NewRPCServiceServer(coll resource.APIResourceCollection[Encoder]) interface{}
• func PropertiesToProtoResponse(props Properties) (*pb.GetPropertiesResponse, error)
• func ToProtoPositionType(positionType PositionType) pb.PositionType
• type Encoder
  • func FromDependencies(deps resource.Dependencies, name string) (Encoder, error)
  • func FromRobot(r robot.Robot, name string) (Encoder, error)
  • func NewClientFromConn(ctx context.Context, conn rpc.ClientConn, remoteName string, ...) (Encoder, error)
• type PositionType
  • func ToEncoderPositionType(positionType *pb.PositionType) PositionType
  • func (t PositionType) String() string
• type Properties
  • func ProtoFeaturesToProperties(resp *pb.GetPropertiesResponse) Properties

Constants

const SubtypeName = "encoder"

SubtypeName is a constant that identifies the component resource API string "encoder".

Variables

var API = resource.APINamespaceRDK.WithComponentType(SubtypeName)

API is a variable that identifies the component resource API.

Functions

func Named

func Named(name string) resource.Name

Named is a helper for getting the named Encoder's typed resource name.

func NamesFromRobot

func NamesFromRobot(r robot.Robot) []string

NamesFromRobot is a helper for getting all encoder names from the given Robot.

func NewEncodedMotorPositionTypeUnsupportedError

func NewEncodedMotorPositionTypeUnsupportedError(props Properties) error

NewEncodedMotorPositionTypeUnsupportedError returns a standard error for when an encoded motor tries to use an encoder that doesn't support Ticks.

func NewPositionTypeUnsupportedError

func NewPositionTypeUnsupportedError(positionType PositionType) error

NewPositionTypeUnsupportedError returns a standard error for when an encoder does not support the given PositionType.

func NewRPCServiceServer

func NewRPCServiceServer(coll resource.APIResourceCollection[Encoder]) interface{}

NewRPCServiceServer constructs an Encoder gRPC service serviceServer.

func PropertiesToProtoResponse

func PropertiesToProtoResponse(
	props Properties,
) (*pb.GetPropertiesResponse, error)

PropertiesToProtoResponse takes a properties struct and converts it to a GetPropertiesResponse.

func ToProtoPositionType

func ToProtoPositionType(positionType PositionType) pb.PositionType

ToProtoPositionType takes a map of PositionType-to-int (indicating the PositionType) and converts it to a GetPositionResponse.

Types

type Encoder

type Encoder interface {
	resource.Resource

	// Position returns the current position in terms of ticks or degrees, and whether it is a relative or absolute position.
	Position(ctx context.Context, positionType PositionType, extra map[string]interface{}) (float64, PositionType, error)

	// ResetPosition sets the current position of the motor to be its new zero position.
	ResetPosition(ctx context.Context, extra map[string]interface{}) error

	// Properties returns a list of all the position types that are supported by a given encoder.
	Properties(ctx context.Context, extra map[string]interface{}) (Properties, error)
}

A Encoder turns a position into a signal.

Position example:

myEncoder, err := encoder.FromRobot(machine, "my_encoder")
if err != nil {
  logger.Fatalf("cannot get encoder: %v", err)
}

// Get the position of the encoder in ticks
position, posType, err := myEncoder.Position(context.Background(), encoder.PositionTypeTicks, nil)

ResetPosition example:

myEncoder, err := encoder.FromRobot(machine, "my_encoder")
if err != nil {
  logger.Fatalf("cannot get encoder: %v", err)
}

err = myEncoder.ResetPosition(context.Background(), nil)

Properties example:

myEncoder, err := encoder.FromRobot(machine, "my_encoder")

// Get whether the encoder returns position in ticks or degrees.
properties, err := myEncoder.Properties(context.Background(), nil)

func FromDependencies

func FromDependencies(deps resource.Dependencies, name string) (Encoder, error)

FromDependencies is a helper for getting the named encoder from a collection of dependencies.

func FromRobot

func FromRobot(r robot.Robot, name string) (Encoder, error)

FromRobot is a helper for getting the named encoder from the given Robot.

func NewClientFromConn

func NewClientFromConn(
	ctx context.Context,
	conn rpc.ClientConn,
	remoteName string,
	name resource.Name,
	logger logging.Logger,
) (Encoder, error)

NewClientFromConn constructs a new Client from connection passed in.

type PositionType

type PositionType byte

PositionType is an enum representing the encoder's position.

const (
	PositionTypeUnspecified PositionType = iota
	// PositionTypeTicks is for relative encoders
	// that report how far they've gone from a start position.
	PositionTypeTicks
	// PositionTypeDegrees is for absolute encoders
	// that report their position in degrees along the radial axis.
	PositionTypeDegrees
)

Known encoder position types.

func ToEncoderPositionType

func ToEncoderPositionType(positionType *pb.PositionType) PositionType

ToEncoderPositionType takes a GetPositionResponse and returns an equivalent PositionType-to-int map.

func (PositionType) String

func (t PositionType) String() string

type Properties

type Properties struct {
	TicksCountSupported   bool
	AngleDegreesSupported bool
}

Properties holds the properties of the encoder.

func ProtoFeaturesToProperties

func ProtoFeaturesToProperties(resp *pb.GetPropertiesResponse) Properties

ProtoFeaturesToProperties takes a GetPropertiesResponse and returns an equivalent Properties struct.