Skip to content

Vultrabot Behavior Tree Demo

This demo implements a far more complex behavior tree than the simple ones in the Pacman and Robot demos.

The Behavior Tree for this demo is essentially the entire tree defined in the Behavior Logic section.

Demo Output

Usage

# if vultron package is installed
# run the demo
$ vultrabot
# or
$ vultrabot --cvd

# print the tree and exit
$ vultrabot --cvd --print-tree

# if vultron package is not installed
$ python -m vultron.bt.base.demo.vultrabot

When the tree is run, it will look something like this:

                     msgs_received_this_tick      q_rm      q_em    q_cs                    msgs_emitted_this_tick                                     CVD_role
1                                         ()     START      NONE  vfdpxa                                        ()  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
2   (RS, RS, CV, CV, RK, CV, RK, CK, CK, CK)     START      NONE  vfdpxa  (RS, CV, CV, RK, CV, RK, CK, CK, CK, RV)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
3                                   (RV, RK)     VALID      NONE  Vfdpxa                              (RK, RA, EP)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
4                           (RA, EP, RK, EK)  ACCEPTED  PROPOSED  Vfdpxa                              (RK, EK, ER)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
5                                   (ER, EK)  ACCEPTED      NONE  Vfdpxa                                  (EK, EP)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
6                                   (EP, EK)  ACCEPTED  PROPOSED  Vfdpxa                                  (EK, EA)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
7                                   (EA, EK)  ACCEPTED    ACTIVE  Vfdpxa                                  (EK, EV)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
8                                   (EV, EK)  ACCEPTED    REVISE  Vfdpxa                                  (EK, EA)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
9                                   (EA, EK)  ACCEPTED    ACTIVE  Vfdpxa                                     (EK,)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
10                          (CA, ET, CK, EK)  ACCEPTED    ACTIVE  Vfdpxa                              (ET, CK, EK)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
11                                        ()  ACCEPTED    EXITED  VfdpxA                                        ()  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
12                                  (CP, CK)  ACCEPTED    EXITED  VfdpxA                                     (CK,)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
13                                        ()  ACCEPTED    EXITED  VfdPxA                                     (CF,)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
14                                  (CF, CK)  ACCEPTED    EXITED  VFdPxA                                     (CK,)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
15                                        ()  ACCEPTED    EXITED  VFdPxA                                        ()  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
18                                        ()  ACCEPTED    EXITED  VFdPxA                                     (CD,)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
19                                  (CD, CK)  ACCEPTED    EXITED  VFDPxA                                  (CK, RD)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
20                          (RD, CA, RK, CK)  DEFERRED    EXITED  VFDPxA                              (RK, CK, RC)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR
21                          (RD, CA, RK, CK)    CLOSED    EXITED  VFDPxA                              (RK, CK, RC)  FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR

The full tree is too large to display here, but you can run the demo to see it.

Demo Code

vultron.demo.vultrabot

Provides a simulated Vultron behavior tree simulator bot.

main(args)

Instantiates a CvdProtocolBt object and runs it until either it closes or 1000 ticks have passed. This demo is basically simulating a CVD agent coordinating a CVD case with itself. The agent's role is set to FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR, which means it will perform all the roles in the CVD case. Messages emitted in one tick might be received later in the same tick, or in a future tick.

Tip

This demo leverages the ability to use leaf nodes as stochastic process fuzzers. Using this feature, we can simulate the behavior of a CVD agent without having to implement any actual communication mechanisms or simulate any complex real-world processes.

One interesting effect of this design is that the places where the demo uses a fuzzer node are often indicative of places where an actual bot would either need to call out to either a data source or a human to decide what to do next. This is a good example of how the Vultron behavior tree can be used to model complex reactive processes in a way that is still easy to understand and reason about.

Note

There is no underlying communication mechanism in this demo, so messages are not actually sent anywhere. Instead, they are just added to the blackboard's incoming message queue. They also have no content, and are only represented as message types.

Warning

This demo is not intended to be a fully realistic simulation of a CVD case. It is only intended to demonstrate the behavior of the Vultron behavior tree.

Source code in vultron/demo/vultrabot.py 
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
def main(args) -> None:
    """
    Instantiates a `CvdProtocolBt` object and runs it until either it closes or 1000 ticks have passed.
    This demo is basically simulating a CVD agent coordinating a CVD case with itself.
    The agent's role is set to `FINDER_REPORTER_VENDOR_DEPLOYER_COORDINATOR`, which means it will
    perform all the roles in the CVD case.
    Messages emitted in one tick might be received later in the same tick, or in a future tick.

    !!! tip

         This demo leverages the ability to use leaf nodes as stochastic process fuzzers.
         Using this feature, we can simulate the behavior of a CVD agent without having to
         implement any actual communication mechanisms or simulate any complex real-world processes.

         One interesting effect of this design is that the places where the demo uses a fuzzer node are often
         indicative of places where an actual bot would either need to call out to either a data source or
         a human to decide what to do next. This is a good example of how the Vultron behavior tree
         can be used to model complex reactive processes in a way that is still easy to understand and reason about.

    !!! note

         There is no underlying communication mechanism in this demo, so messages are not actually
         sent anywhere. Instead, they are just added to the blackboard's incoming message queue.
         They also have no content, and are only represented as message types.

    !!! warning

         This demo is not intended to be a fully realistic simulation of a CVD case. It is only intended
         to demonstrate the behavior of the Vultron behavior tree.
    """
    _setup_logger(args)

    if args.print_tree:
        logger.info("Printing tree and exiting")
        show_graph(CvdProtocolRoot)
        sys.exit()

    _run_simulation()
    _print_sim_result()