ROS2 Message Definitions

The underlying communication provides data interaction between the client PC and the robot.

Subscribe to topic lowstate (Type: pnd_adam.msg.dds_.LowState_) to get the current state of Adam.
Subscribe to topic handstate (Type: pnd_adam.msg.dds_.HandState_) to get the current state of the fingers.
Publish to topic lowcmd (Type: pnd_adam.msg.dds_.LowCmd_) to control whole-body joint motors (excluding dexterous hands), batteries, and other equipment.
Publish to topic handcmd (Type: pnd_adam.msg.dds_.Handcmd_) to control finger joint motors.

Interface Description

Use ROS2 to subscribe to or publish topics. Topic information is stored in structures defined by IDL. Common structures include:

Structure Name	Description
`_BatteryData_.py`	Battery status (voltage, current, power, etc.)
`_HandCmd_.py`	Dexterous hand desired position control
`_HandState_.py`	Dexterous hand actual status feedback
`_IMUState_.py`	Adam IMU attitude and acceleration data
`_LowCmd_.py`	Adam low-level whole-body control commands
`_LowState_.py`	Adam low-level whole-body status summary
`_MotorCmd_.py`	Single motor control parameters (position, velocity, torque, and gains)
`_MotorState_.py`	Single motor status feedback

DDS Message Definitions

Published Message: lowcmd (Desired Body Position)

Field	Type	Dimension	Meaning
`mode_pr`	`uint8`	1	Mode control
`motor_cmd`	`MotorCmd_`	*	Variable length^[1]
`reserve`	`uint32`	1	Reserved field

[1] motor_cmd description: The length depends on the robot model:

Adam U: 19-dimensional actuator data

Subscribed Message: lowstate (Actual Body State)

Field	Type	Dimension	Meaning
`mode_pr`	`uint8`	1	Current mode state
`tick`	`uint32`	1	System timestamp/ticks
`imu_state`	`IMUState_`	9	IMU attitude data
`motor_state`	`MotorState_`	*	Variable length^[1]
`wireless_remote`	`short`	40	Wireless controller data^[2]
`battery_data`	`BatteryData_`	1	Battery level and status information
`reserve`	`uint32`	1	Reserved field

[1] motor_state description: The length depends on the robot model:

Adam U: 19-dimensional actuator data

[2] wireless_remote description: Indices 20-40 are empty. 0-19 correspond to the controller buttons: "lx", "ly", "rx", "ry", "lt", "rt", "xx", "yy", "a", "b", "x", "y", "lb", "rb", "back", "start", "home", "lo", "ro".

Auxiliary Structure Definitions

Battery Status Type: BatteryData_

Field	Type	Meaning
`timestamp_ms`	`int64`	Millisecond timestamp
`voltage`	`float32`	Voltage (V)
`current`	`float32`	Current (A)
`power`	`float32`	Power (W)
`wh_accumulated`	`float32`	Accumulated power consumption (Wh)
`status`	`string`	Battery status description

IMU Data Type: IMUState_

Field	Type	Dimension	Meaning
`quaternion`	`float32`	4	Quaternion [w, x, y, z]
`gyroscope`	`float32`	3	Angular velocity [x, y, z]
`accelerometer`	`float32`	3	Acceleration [x, y, z]
`ypr`	`float32`	3	Attitude angles [yaw, pitch, roll]
`temperature`	`int16`	1	Sensor temperature

Single Joint Control Type: MotorCmd_

Field	Type	Meaning
`mode`	`uint8`	Mode (default is 0)
`q`	`float32`	Desired position (rad)
`dq`	`float32`	Desired velocity (rad/s)
`tau`	`float32`	Desired torque (Nm)
`kp`	`float32`	Proportional gain (Stiffness)
`kd`	`float32`	Derivative gain (Damping)
`ki`	`float32`	Integral gain
`reserve`	`uint32`	Reserved field

Single Joint State Type: MotorState_

Field	Type	Meaning
`mode`	`uint8`	Current mode
`q`	`float32`	Actual position (rad)
`dq`	`float32`	Actual velocity (rad/s)
`ddq`	`float32`	Actual acceleration (\(\text{rad/s}^2\))
`tau_est`	`float32`	Estimated torque (Nm)
`state`	`uint32`	Motor operation status code
`reserve`	`uint32`	Reserved field

Dexterous Hand Interface

Published Message: handcmd (Desired Finger Position)

Field	Type	Dimension	Meaning
`position`	`uint32`	12	Desired hand position
`reserve`	`uint32`	1	Reserved field

Subscribed Message: handstate (Actual Finger State)

Field	Type	Dimension	Meaning
`position`	`uint32`	12	Actual hand position
`reserve`	`uint32`	1	Reserved field