State Reading

Full State Snapshot

Read the complete arm state in one call, including TCP pose plus angle, velocity, acceleration, torque, and temperature for all joints.

from realhand import A7lite

with A7lite(side="left", interface_name="can0") as arm:
    arm.enable()
    state = arm.get_state()
    print(state.pose)
    print(f"Actual angle of the first joint: {state.joint_angles[0].angle:.4f} rad")

Return value

State: Contains pose, joint_angles, joint_control_angles, joint_velocities, joint_control_velocities, joint_control_acceleration, joint_torques, and joint_temperatures

`State` data model

Field	Description
`pose`	TCP pose (`Pose`)
`joint_angles`	Actual angles of the 7 joints (`list[AngleState]`)
`joint_control_angles`	Control angles of the 7 joints (`list[AngleState]`)
`joint_velocities`	Actual velocities of the 7 joints (`list[VelocityState]`)
`joint_control_velocities`	Control velocities of the 7 joints (`list[VelocityState]`)
`joint_control_acceleration`	Control accelerations of the 7 joints (`list[AccelerationState]`)
`joint_torques`	Actual torques of the 7 joints (`list[TorqueState]`)
`joint_temperatures`	Temperatures of the 7 joints (`list[TemperatureState]`)

Each sub-state model (AngleState, VelocityState, etc.) includes a value field and a timestamp (Unix time in seconds).

Sub-state model fields

Model	Value field	Timestamp field
`AngleState`	`.angle`	`.timestamp`
`VelocityState`	`.velocity`	`.timestamp`
`AccelerationState`	`.acceleration`	`.timestamp`
`TorqueState`	`.torque`	`.timestamp`
`TemperatureState`	`.temperature`	`.timestamp`

Read Individual State Items

Besides get_state(), the following methods return a single kind of state. All of them return lists for 7 joints, except get_pose().

from realhand import A7lite

with A7lite(side="left", interface_name="can0") as arm:
    arm.enable()
    angles = arm.get_angles()
    velocities = arm.get_velocities()
    temps = arm.get_temperatures()
    pose = arm.get_pose()
    print(f"Actual angle of the second joint: {angles[1]:.4f} rad")
    print(f"Actual velocity of the third joint: {velocities[2]:.4f} rad/s")
    print(f"Actual temperature of the fourth joint: {temps[3]:.1f} °C")
    print(f"TCP: ({pose.x:.3f}m, {pose.y:.3f}m, {pose.z:.3f}m)")

Return values

Method	Return value	Unit
`get_angles()`	Actual angles of 7 joints	rad
`get_control_angles()`	Control angles of 7 joints	rad
`get_velocities()`	Actual velocities of 7 joints	rad/s
`get_control_velocities()`	Control velocities of 7 joints	rad/s
`get_control_acceleration()`	Control accelerations of 7 joints	rad/s²
`get_torques()`	Actual torques of 7 joints	Nm
`get_temperatures()`	Temperatures of 7 joints	°C
`get_pose()`	TCP pose	m, rad

Sensor Data

A7 Lite uses active motor reporting mode, which starts automatically during construction.

Data type	Unit	Report rate
Angle	rad	Determined by motor report period
Velocity	rad/s	Same as above
Torque	Nm	Same as above
Temperature	°C	Same as above

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