Why doesn't my AI character move?

I’m trying to move a AICaracter.
I’m testing with this tutorial:

or this one (post nr 5 )

But I cant make my AI move.
The only difference I see between what is explained in the tutorials and what I have is:

When creating a key of my BlackBoard, I dont have “BlackboardKeyType_Vector” key type.
I must select a “class” or “object” keytype and then indicate “BlackboardKeyType_Vector” type, like is shown in the attached screen.

if I choose one of these keys, they are always in “None” or empty.
If I choose the key as a “vector” type, it is filled with randomized positions, but anyway my AI doesnt move.

If you have any ideas or if there is a bug in version 4.3 of the engine, lplease et me know

thank you very much

Have you tried using something other than get Random Point in Radius when setting the BBVector?

Hi Alexarg,

So there are a few reasons that may not be happening. First, check to see if your NavMeshBoundsVolume is generating paths; Press ‘P’ to enable seeing NavMesh paths in viewport. Once those are generating correctly, look into your behavior tree with your AI targeted and see if the execution is getting stuck anywhere. Try throwing in a few Print Strings in your BPs to make sure your executions are firing at all. If you are still getting stuck, it may help to attach some screenshots of your Behavior Tree and Blueprints.

I actually have a working version of that tutorial’s AI in a test level, so I would like to compare what we have.



Not sure how helpful this is, but I had a similar issue with the tutorials from Peter Newton. In the end, after doing a lot of what Alexander suggests above, the culprit was a setting in the character changing the walk speed with a variable set in one of the blackboard keys. No idea why or how I did that part wrong, but disconnecting that from the character blueprint made everything work fine for pathing. Strangely, the behavior I found with the AI was that even though it appeared to not be moving, it actually was. Just about 1/100th the speed it should have been. While simulating, I could lift the little guy off the ground a bit and he would scurry on his way. Use the debug tools in the editor to see if the AI even has a path, they clued me into the movement speed issue since he knew where he wanted to go, but was just too slow.

Thank you very much SilentX, Gooner44 and Alexander for the replies, I attach the screens with my settings.
All events, including BP, the task and the behaivor Tree are shooting.

as I said the only difference with the tutorial that i ollowed is setting of the key on the blackboard

On the screen i uploaded i am testing with a key of type Vector, which is the only one that returns me a result.
If I try to Object->BlackBoardKeyType_Vector or class >BlackBoardKeyType_Vector i simply get Null (or none) , maybe this is the problem?


edit: My IA moves to a location calling only “move to location” in the controller (with out a Behavior Tree)

thanks for your answer.
I confirm that my AI moves to a location calling only “move to location” in the controller and it actually moves, but when I do it by behavior trees, the same problem happens.
The capsule componente have 88 height 44 radius.

i havent dabbled in behavior trees at all, but i once had a character that wouldnt move at ALL, even with using the SimpleMoveToLocation function which should always work. i had the path nav mesh bounds setup it showed fine but for some reason it would not move what so ever.

i got ■■■■■■ as all hell and made a new character and got the SimpleMove function to work just fine and then it broke again when i made the characters capsule component larger than 200 in either radius or height.

so just to rule out this weird bug i found, make sure your character even move with manually calling this SimpleMove function and then make sure ur capsule component is the normal 88 height 44 radius.

sorry if this doesnt help or if im completely of topic here


So I looked through the images provided and I have a few suggestions.

In the image “BT” I noticed that the MoveTo target was “Invalid” that needs to be linked to the vector variable.

Also, the Get Random Point in Radius has a very small radius (100), try setting that to 1000. The MoveTo node has an “Acceptable Radius” variable that lets the AI know when it is close to the target point, but if it is too high then it will think that it is already at the desired location.

Can you please put a print string in the task to output the chosen vector? That way we can at least know that it is getting that far, then we can see why it would not be communicating that to the MoveTo node.

Thank you,


Yes!! it was the Get Random Point in Radius with a very small radius!
Now all I have to do the animations run properly, Now my AIcharacter walks backwards or sideways with the walking animation playing to another place

I feel like a fool, thank you very much for the help and your time.

Sometimes. I don’t know whether it’s bug or something. Try it.
Click on the character which is not moving