Current Time

Retrieve current ROS time or system time

• 

Libraries:
ROS Toolbox / ROS

Description

The Current Time block outputs the current ROS or system time. ROS Time is based on the system clock of your computer or the /clock topic being published on the ROS node.

Use this block to synchronize your simulation time with your connected ROS node.

If the use_sim_time ROS parameter is set to true, the block returns the simulation time published on the /clock topic. Otherwise, the block returns the system time of your machine.

Examples

Time Stamp a ROS Message Using Current Time in Simulink

Time stamp a ROS message with the current system time of your computer.

• Open Live Script

Ports

Output

Time — ROS time

bus | scalar

ROS time, returned as a bus signal or a scalar. The bus represents a rosgraph_msgs/Clock ROS message with Sec and NSec elements. The scalar is the ROS time in seconds. If no time has been received on the /clock topic, the block outputs 0.

Data Types: bus | double

Parameters

Output format — Format of ROS time

bus (default) | double

Format of ROS Time output, specified as either bus or double.

Sample time — Interval between outputs

-1 (default) | numeric scalar

Interval between outputs, specified as a numeric scalar.

For more information, see Specify Sample Time (Simulink).

Tips

• To set the use_sim_time parameters and get time from a /clock topic:

  Connect to a ROS network, then use the Set Parameter block or set the parameter in the MATLAB^® command window:

  ptree = rosparam;
  set(ptree,'/use_sim_time',true)

  Usually, the ROS node that publishes on the /clock topic sets up the parameter.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2019b