Concurrent states

[chrisbitter]

I am currently exploring YASMIN as alternative to Smach for ROS2. Is it possible to model concurrent states (analogous to https://wiki.ros.org/smach/Tutorials/Concurrent%20States)?

If not, any idea of how this can be integrated? Happy to contribute.

[mgonzs13]

Hey @chrisbitter, this will be a great feature to add to YASMIN. A primitive version could be this, but the outcomes of the states and the cancelations should be added. In this case, a set of states are executed concurrently and the same outcome is returned in any case. Do you have any suggestions?

from threading import Thread
from typing import List
from yasmin import State
from yasmin.blackboard import Blackboard

class Concurrence(State):

    def __init__(self, outcome: str, states: List[State]) -> None:

        super().__init__([outcome])

        self.states = states

    def execute(self, blackboard: Blackboard) -> str:

        state_threads = []

        for s in self.states:
            state_threads.append(Thread(target=s, args=(blackboard,)))
            state_threads[-1].run()

        for t in state_threads:
            t.join()

        return self._outcomes[0]

[mgonzs13]

Hey @chrisbitter, how is this going?