dg_sdk_ros2_bridge

ROS 2 bridge for the Delto Gripper SDK (DG SDK).

Warning

The DG SDK (libDGSDK.so) is only available for x86_64 architectures. This package cannot be used on ARM-based platforms (such as NVIDIA Jetson or Raspberry Pi).

Note

Ensure the bundled SDK version matches your gripper firmware. Check the SDK release notes for compatibility information.

Overview

The dg_sdk_ros2_bridge package provides a ROS 2 node that wraps the proprietary DG SDK library, exposing all gripper functions as ROS 2 topics and services. This is an alternative to using delto_hardware with ros2_control.

Note

What is the difference between the SDK bridge and ros2_control? The ros2_control approach (delto_hardware) gives you a standardized hardware interface that works with standard ROS 2 controllers, MoveIt, and the broader ROS 2 ecosystem. The SDK bridge gives you direct access to all proprietary SDK functions – including recipe management, advanced gain tuning, blend motion, TCP space control, and more. Choose based on your needs.

When to Use Which

Use Case	Recommended Approach
Standard position/effort control	delto_hardware (ros2_control)
MoveIt integration	delto_hardware (ros2_control)
Trajectory following	delto_hardware (ros2_control)
Recipe management	dg_sdk_ros2_bridge
Use the same functions as the DGManager program	dg_sdk_ros2_bridge
Blend motion (multi-waypoint smooth paths)	dg_sdk_ros2_bridge

Warning

Important: The gripper only accepts one TCP connection at a time. You cannot run delto_hardware and dg_sdk_ros2_bridge simultaneously for the same gripper. Choose one approach per gripper instance.

Architecture

Your Application
    |
    v  (ROS 2 topics & services)
dg_sdk_ros2_bridge node
    |
    v  (C++ function calls)
DG SDK (libDGSDK.so)
    |
    v  (TCP/IP)
Gripper Firmware

The bridge node acts as a translator: it receives ROS 2 service calls from your application and forwards them to the proprietary DG SDK library, which handles the actual communication with the gripper.

Published Topics

The bridge node continuously publishes gripper data on these topics:

Topic	Type	Rate	Description
/dg/gripper_data	dg_msgs/ReceivedGripperData	Continuous	Joint positions, velocities, currents, and temperatures
/dg/fingertip_sensor_data	dg_msgs/ReceivedFingertipSensorData	Continuous	F/T sensor readings (6 values per finger)
/dg/gpio_data	dg_msgs/ReceivedGPIOData	Continuous	GPIO input/output states
/dg/diagnosis_system	dg_msgs/DiagnosisSystem	Continuous	System diagnostic information

Services by Category

The bridge exposes 86+ services for full SDK functionality. Here they are organized by category:

System Settings

Service	Description
SetGripperSystem	Configure gripper system parameters
SetGripperOption	Set gripper options
ConnectToGripper	Establish connection to the gripper
DisconnectToGripper	Close connection
SystemStart	Start the gripper system
SystemStop	Stop the gripper system
SetIp	Configure the gripper’s IP address

System Configuration

Service	Description
SetLowPassFilterAlpha	Set low-pass filter coefficient for sensor data smoothing
SetBootMode	Configure how the gripper behaves on power-up
SetGPIOOutput	Set a single GPIO output
SetGPIOOutputAll	Set all GPIO outputs at once
SetTorqueLimitMode	Configure motor torque limiting
SetBootRecipe	Set which recipe runs automatically on boot
EEPROMWrite	Write configuration to the gripper’s persistent storage
SystemDiagnosis	Run a system diagnostic check
BackupRecipeData	Backup all recipes from the gripper
RestoreRecipeData	Restore recipes to the gripper

Joint Gain Settings (PID Tuning)

Service	Description
SetJointGainP / PFinger / PAll	Set proportional gain (per joint, per finger, or all joints)
SetJointGainD / DFinger / DAll	Set derivative gain
SetJointGainI / IFinger / IAll	Set integral gain
SetJointGainPID / PIDFinger / PIDAll / PIDAllEqual	Set all PID gains together
SetControlPIDMode	Switch between PID control modes

Motion Time

Service	Description
SetMotionTimeJoint / Finger / All / AllEqual	Set how long a motion should take (per joint, per finger, or all)

Position and Current Control

Service	Description
SetPositionModeJoint / Finger / All	Enable position control mode
SetCurrentControlMode	Enable direct current control mode
SetTargetCurrentJoint / Finger / All	Set target motor current

Motion Commands

Service	Description
MoveJoint / MoveJointFinger / MoveJointAll	Move joints to target positions
MoveServoJoint	Real-time servo mode for smooth continuous motion
ManualTeachMode	Enable/disable manual teach mode (freely move joints by hand)
StartGraspMotion	Execute a pre-configured grasp motion
SetGraspData / SetGraspForce	Configure grasp parameters and force limits

TCP (Tool Center Point) Control – Experimental

Service	Description
SetTCPGainP/D/I/PID (Finger/All)	Set PID gains for TCP space control
SetTCPMotionTime (Finger/All/AllEqual)	Set motion time for TCP space motions
MoveTCPFinger / MoveTCPAll	Move fingertips to target poses in Cartesian space
GetCurrentTcpPose	Get current TCP (fingertip) pose
SetManipulationGainPIDAll	Set PID gains for in-hand manipulation
InHandManipulation	Execute in-hand manipulation
SetFingerTipDataZero	Zero the fingertip sensor data

Recipe Management

Service	Description
UpdateRecipeCurrentPoseData	Save the current pose as a recipe
UpdateRecipeTargetPoseData	Save a target pose as a recipe
LoadRecipePoseData	Load a saved pose recipe
UpdateRecipeGainData	Save current PID gains as a recipe
LoadRecipeGainData	Load saved PID gain settings
UpdateRecipeGraspData	Save grasp parameters as a recipe
LoadRecipeGraspData	Load saved grasp parameters

Blend Motion (Multi-Waypoint)

Service	Description
UpdateBlendJoint	Update a blend motion waypoint
AddMoveBlendJoint	Add a waypoint to the blend queue
ClearMoveBlendJoint	Clear all waypoints from the blend queue
SetMoveBlendJoint	Configure blend motion parameters
StartMoveBlendJoint	Execute the blend motion
StopMoveBlendJoint	Stop the currently running blend motion

Data Getters

Service	Description
GetReceivedGripperData	Get the latest gripper data on demand
GetReceivedFingertipSensorData	Get the latest F/T sensor data
GetReceivedGPIOData	Get the latest GPIO states
GetCommunicationPeriod	Get the current communication cycle time
GetDataProcessing	Get the data processing status
GetDiagnosisSystem	Get the latest diagnostic information

Step-by-Step Usage Example

Here is a basic workflow for using the SDK bridge:

Step 1: Launch the bridge node.

ros2 run dg_sdk_ros2_bridge dg_sdk_ros2_bridge_node

Step 2: Configure and connect to the gripper.

# Set up the gripper system parameters
ros2 service call /dg/SetGripperSystem dg_msgs/srv/SetGripperSystem "{...}"

# Connect to the gripper
ros2 service call /dg/ConnectToGripper dg_msgs/srv/ConnectToGripper "{...}"

# Start the system
ros2 service call /dg/SystemStart dg_msgs/srv/SystemStart "{}"

Step 3: Monitor gripper data.

# Watch joint positions, velocities, and currents
ros2 topic echo /dg/gripper_data

# Watch F/T sensor data
ros2 topic echo /dg/fingertip_sensor_data

Step 4: Send motion commands.

# Move all joints to target positions
ros2 service call /dg/MoveJointAll dg_msgs/srv/MoveJointAll "{...}"

Step 5: Stop and disconnect.

ros2 service call /dg/SystemStop dg_msgs/srv/SystemStop "{}"
ros2 service call /dg/DisconnectToGripper dg_msgs/srv/DisconnectToGripper "{}"

Message Types

All custom messages and services used by the bridge are defined in the dg_msgs package. See Message Definitions and Service Definitions for complete definitions.