I tried to create behavior tree example using selector. But I am getting error
“PANIC engine/alice/backend/modules.cpp@280: Could not load component 'isaac::behavior_tree::MemorySelectorBehavior’”
Can somebody please help me with that. I have attached image of python file and json file
Also would like to request NVIDIA team to upload complete example of behavior tree not only json file
Hi @nasrin.saiyed,
When using components from different modules in your app, the modules must be 1) added as a dependency in the BUILD file, and 2) loaded into the application. For your case, make sure you have behavior_tree under modules in the bazel rule for the app. To load the module after defining the application, use app.load_module('behavior_tree') in main().
The cart delivery application serves as a working example for the behavior tree components. See the docs here.
Thank you for using Isaac!
A working example of the MemorySelectorBehavior inspired from the above question.
BUILD File
load("//bzl:py.bzl", "isaac_py_app")
isaac_py_app(
name = "selector_example",
srcs = [
"__init__.py",
"selector_example.py",
],
data = [
"selector_example.app.json",
"//apps:py_init",
],
modules = [
"behavior_tree",
],
deps = [
"//packages/pyalice",
],
)
filegroup(
name = "py_init",
data = ["__init__.py"],
visibility = ["//visibility:public"],
)
JSON File
{
"name" : "selector_example",
"modules" : [
"behavior_tree"
],
"graph" : {
"nodes" : [
{
"name" : "selector_node",
"components" : [
{
"name" : "NodeGroup",
"type" : "isaac::behavior_tree::NodeGroup"
},
{
"name" : "MemorySelectorBehavior",
"type" : "isaac::behavior_tree::MemorySelectorBehavior"
}
]
},
{
"name" : "child_node_1",
"components" : [
{
"name" : "node_1",
"type" : "isaac::alice::PyCodelet"
}
],
"disable_automatic_start" : true
},
{
"name" : "child_node_2",
"components" : [
{
"name" : "node_2",
"type" : "isaac::alice::PyCodelet"
}
],
"disable_automatic_start" : true
}
]
},
"config" : {
"selector_node" : {
"NodeGroup" : {
"node_names" : [
"child_node_1",
"child_node_2"
]
}
}
}
}
PyCodelets
from isaac import Application, Codelet
class node_1(Codelet):
def start(self):
self.count = 0
self.tick_periodically(1.0)
def tick(self):
self.count += 1
if self.count > 3:
print("Failure? count from Codelet: child_node_1: ", self.count)
self.report_failure('Status set to Failure to trigger the child_node_2')
else:
print("Success! count from Codelet: child_node_1: ", self.count)
class node_2(Codelet):
def start(self):
# pass
self.count = 0
self.tick_periodically(1.0)
def tick(self):
self.count += 1
print("Success! Codelet: child_node_2 count: ", self.count)
if self.count > 2:
self.report_failure('Status set to Failure to stop execution of child_node_2')
def main():
app = Application(app_filename = "apps/selector_example.app.json")
app.nodes["child_node_1"].add(node_1, "node_1")
app.nodes["child_node_2"].add(node_2, "node_2")
app.run()
if __name__ == "__main__":
main()