Basics

Architecture Overview

The SDK uses a modular design. All features are accessed through the main class:

L6
├── hand.angle          # Angle control
├── hand.speed          # Speed control
├── hand.torque         # Torque control
├── hand.current        # Current reading
├── hand.temperature    # Temperature reading
├── hand.force_sensor   # Force sensors
├── hand.fault          # Fault handling
└── hand.version        # Version information

Calling Convention

All features are called through hand.module.method():

from realhand import L6

with L6(side="left", interface_name="can0") as hand:
    hand.angle.set_angles([50, 50, 50, 50, 50, 50])
    hand.speed.set_speeds([100, 100, 100, 100, 100, 100])

    data = hand.temperature.get_blocking()

Type Safety

The SDK provides typed data classes with IDE autocompletion support:

from realhand import L6
from realhand.hand.l6 import L6Angle

with L6(side="left", interface_name="can0") as hand:
    # Use a data class (recommended, with type hints)
    angle = L6Angle(thumb_flex=50, thumb_abd=30, index=60, middle=60, ring=60, pinky=60)
    hand.angle.set_angles(angle)

    # Or use a list (more concise)
    hand.angle.set_angles([50, 30, 60, 60, 60, 60])

Data class fields:

Data Reading Modes

Blocking Read

Send a request and wait for a response:

data = hand.angle.get_blocking(timeout_ms=100)

Cached Read

Get the most recently received data without blocking:

data = hand.angle.get_snapshot()
if data is not None:
    print(data.angles)

Streaming Read

Continuously receive data from the unified event stream:

from realhand.hand.l6 import SensorSource, AngleEvent

hand.start_polling({SensorSource.ANGLE: 0.1})

for event in hand.stream():
    match event:
        case AngleEvent(data=data):
            print(data.angles)
    if should_stop():
        break

hand.stop_polling()
hand.stop_stream()

Snapshot

Get the latest cached values from all sensors:

snap = hand.get_snapshot()
print(snap.angle)  # AngleData | None
print(snap.temperature)  # TemperatureData | None

Resource Management

Use a with statement to manage resources automatically:

with L6(side="left", interface_name="can0") as hand:
    # Use the hand
    pass
# Resources are released automatically

Or manage the lifecycle manually:

hand = L6(side="left", interface_name="can0")
try:
    # Use the hand
    pass
finally:
    hand.close()

Exception Handling

from realhand import L6
from realhand.exceptions import TimeoutError, ValidationError

with L6(side="left", interface_name="can0") as hand:
    try:
        data = hand.angle.get_blocking(timeout_ms=100)
    except TimeoutError:
        print("Read timed out")
    except ValidationError as e:
        print(f"Invalid parameter: {e}")

Joint Indexing

All 6-joint modules use the same index order: