ROS 2 Sim-to-Real Robot Control: ros2srrc_data

The ros2srrc_data package contains all different ROS 2 data structures that are required to execute the Source Code defined in the ros2srrc_execution package.

Robot Movement execution

ROS 2 .action

In ros2_SimRealRobotControl, individual Robot Movements contained in a single ROS 2 Node (ROS 2 Action Server, move.cpp), and are executed by calling a single action, called, “Move”.

Move.action:

• Input: action(string), speed (float64), movej (joints), mover (joint), movel (xyz), moverot (ypr), moverp (xyzypr), moveg (float64).
• Output: result(string), feedback(string).

Robmove.action:

• Input: type(string), speed(float64), x(float64), y(float64), z(float64), qx(float64), qy(float64), qz(float64), qw(float64).
• Output: success(bool), message(string), feedback(string).

ROS 2 .msg

Every single Robot Movement type (MoveJ, MoveR, MoveL…) is defined on a specific ROS 2 MSG format:

Joints.msg:

• Data: joint1(float64), joint2(float64), joint3(float64), joint4(float64), joint5(float64), joint6(float64), joint7(float64).

Joint.msg:

• Data: joint(string), value(float64).

Xyz.msg:

• Data: x(float64), y(float64), z(float64).

Xyzypr.msg:

• Data: x(float64), y(float64), z(float64), yaw(float64), pitch(float64), roll(float64).

Ypr.msg:

• Data: yaw(float64), pitch(float64), roll(float64).

Robpose.msg:

• Data: x(float64), y(float64), z(float64), qx(float64), qy(float64), qz(float64), qw(float64).

Specs.msg:

• Data: ee_max(float64), ee_min(float64), ee_vector(float64[]), robot_max(float64[]), robot_min(float64[]).

Linkattacher.msg:

• Data: model1_name(string), link1_name(string), model2_name(string), link2_name(string).

Sequence execution

ROS 2 .action

The sequences/programs are executed by calling the single ROS 2 Action “Sequence”, which contains an array with Robot Movements (defined in “Action.msg”) that are executed one after the other. Instead of having to call the ROS 2 Action “Move” for every single step**, the whole sequence is passed to ExecuteProgram.py, and movements are executed one by one using MoveGroupInterface.

Sequence.action:

• Input: Sequence(action[]), robot(string), endeffector(string), environment(string).
• Output: result(string), feedback(string).

ROS 2 .msg

All possible Robot Movements have been put into the “Action” ROS 2 message, in order to be able to generate an array containing the whole sequence.

Action.msg:

• Data: action(string), speed (float64), movej (joints), mover (joint), movel (xyz), movexyzw (xyzypr), movexyz (xyz), moveypr (ypr), moverot (ypr), moverp (xyzypr), moveg (float64), attach (linkattacher), detach (linkattacher).

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** This method is used in ros2_RobotSimulation, which includes a small delay between steps due to the ROS 2 Action call which needs to be done before every step.