an issue on "Behavior Tree Quick Start Guide".

Hello, guys.
I have followed the lesson “Behavior Tree Quick Start Guide”.
I have done it, but the AI bot didnt moves. I have recheked all my BPs - all are correct (with the lesson).
And I have found that when I start the level in BP “AgroCheck” it stoped on a forEachLoop (see image).
Can anybody help me, please.

Heya ThierryH,
Does your DesiredObjectTypes Array have one entry set to Pawn?

I had a problem where it wasn’t moving in response to the player moving and found that it was not where you have circled. Rather, mine was in the Line Trace By Channel block in the same blueprint. It’s easy to miss that they have the Camera selected as the Trace Channel for it. As soon as I changed it to camera, mine started working. Hope it helps.


Thanks for the reply, and apologize for my late reply.
I attached all my BPs. I have recheked all of them - its the same as in the official lesson.

I am sorry for you because spending so much time and not having the result is always frustrating but i had to test this guide again last week and this tutorial works fine.
Trouble is that your error is in a hidden place where you are “sure” that it is ok. Or error is something not related to guide (character instead of pawn, modified collision, any other change which creates weird effect)
Places to check :
in service : your linetraces (radius 1500 for first one (this one is ok), trace channel : camera for second one),
in task : ai move to : aiconref controlled pawn linked to pawn, acceptance radius set 50. Finish execute input success : check.
Then check all values in your variables like pawn in array desired object types. As Ian Shadden said)

If sadly mistake is not there, Keep time to check point by point

ok, thanks.
I`ll try again)) to check.
And will try to check on a new character, maybe the matter is really in character.

If I get a moment this week I’ll make sure to update the tutorial.

The thing that really calls out to me is that execution doesn’t proceed into the For Each Loop, meaning that nothing is returned, but the trace looks solid. So either 1) the player’s Pawn doesn’t have it’s collision profile set to Pawn or 2) the DesiredObjectTypes Array doesn’t have it’s single entry of Pawn.


or 3) Something else :wink: But, really it’s a rapidly evolving system so I wouldn’t be surprised if this tutorial needs more substantial updates.

Thank you, Ian.
I really have missed an Entry of Pawn for DesiredObjectTypes Array. Its my lost). But now the bot not always see me and also he not always follow me. I used it in 3d person template, maybe the reason in this?

IF this is intermittent, is your navmesh on all ground surface ? (edit : p to see navmesh in editor)

no, it`s not intermittent, its cover all ground

I just did a try to migrate whole system in third person project and it works fine. i send you pm with a link with a folder AI to compare to yours and see where is your trouble

ok, thanks. I`ll try it.

Replace Event Receive Tick node in AgroCheck with Event Receive Tick AI

Hi, I’m having a problem with the tutorial as well.

I’m learning from it with very limited time however. I can’t seem to get the AI to do anything.
I exchanged the skeletal mesh with a static mesh in a separate component because I’m trying to use it as an enemy
but besides that I’ve done everything exactly the same to my knowledge.

As I said I’m doing this with very limited time but I’ve checked everything as detailed as I can.
I’m a student and I had a project to make a game with a team and I wanted to use the tutorial to help with the AI
but it doesn’t seem to be working and I can’t figure out why. I also wanted to suggest that maybe in that tutorial to
also show the pictures for the detail panel as well, as shown in your attached image.

If I knew that then I’d know if all the variables were right, because currently I’m most confused by that strange variable “Follower_AI_CON_C”.
In the variables there’s no “Follower_AI_CON_C”, only “Follower_AI_CON” and a pull-out menu that has four other variable types.

Could you send me a folder of the completed tutorial so I could see what part, or parts, I accidentally left out or made a mistake at?



,then the AI move.thx~

Having the same problem, nothing seem to fix it.
I have a custom character tough, maybe this bring some issues?

So mine does move, if it sees you, when you are out of sight, it moves to the last location you where.

Hey all don’t know if its still an issue but may i recommend this video for beginners with AI

Its an easy AI to follow and modify, I personally think its better then the one in the documentation.