# Can't get forward velocity multiplied with delta seconds consistent

**URL:** <https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744>\
**Category:** Blueprint\
**Tags:** unreal-engine, delta-time, Blueprint\
**Created:** [November 13, 2022, 11:59am UTC](https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744 "2022-11-13T11:59:22Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Calig0la88](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Calig0la88](https://forums.unrealengine.com/u/Calig0la88)\
**Post date:** [November 13, 2022, 11:59am UTC](https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744/1 "2022-11-13T11:59:22Z")

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Hello all,

I have an actor that moves forward, but I don’t understand how to get consistent results with different frame rates. I am trying to multiply for the forward speed with delta seconds, but the results remain inconsistent.

 ![deltaTime](https://d3kjluh73b9h9o.cloudfront.net/original/4X/b/5/7/b57bc71438b030088cf3c4e828399280359c746c.png)  
 ![forwardSpeed](https://d3kjluh73b9h9o.cloudfront.net/original/4X/8/5/f/85fd79c6d3537f46b5bc81844b04d9628ed14e1c.png)

I created a variable from the Event Tick called DeltaTime that gets updates every tick (fist picture). In the function that handles forward movement I tried to implement DeltaTime on several locations, but nothing seems to do the trick.

All variables give the same results with different frame rates, so the values to calculate the forward speed are consistent, so I figured that I probably need to multiply with DeltaTime right before the force is applied. No success however…

I really can’t get my head around this. Can someone point me in the right direction and explain to me why my results are inconsistent?

I appreciate any and all help.

Thanks in advance!

Kind regards,

Niels

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**Author:** ![Calig0la88](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Calig0la88](https://forums.unrealengine.com/u/Calig0la88)\
**Post date:** [November 15, 2022, 8:19am UTC](https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744/2 "2022-11-15T08:19:42Z")

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Any input on the matter would be greatly appreciated.

I tried to rebuild the blueprint and only add force to drive the object forward, but still the result are inconsistent with different frame rates…

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**Author:** ![ClockworkOcean](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/clockworkocean/32/1169999_2.png) [@ClockworkOcean](https://forums.unrealengine.com/u/ClockworkOcean)\
**Post date:** [November 15, 2022, 9:50am UTC](https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744/3 "2022-11-15T09:50:41Z")

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I don’t think you can use delta when force is concerned. It’s really only for correcting other floats.

Technically, physics should work the same regardless of frame rate. You have to enable substepping

> **[Physics Sub-Stepping](https://docs.unrealengine.com/4.27/en-US/InteractiveExperiences/Physics/Substepping/)**
>
> Explanation of what Physics Sub-Stepping is and when to use it.

If that still doesn’t work, you pretty much on your own. I did see this

> **[Framerate independent physics in UE4 · Víctor Ávila](https://avilapa.github.io/post/framerate-independent-physics-in-ue4/)**
>
> How to achieve physics framerate independence by correctly using UE4 substepping.

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<div class="post-metadata">

**Author:** ![Calig0la88](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Calig0la88](https://forums.unrealengine.com/u/Calig0la88)\
**Post date:** [November 15, 2022, 2:46pm UTC](https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744/4 "2022-11-15T14:46:10Z")

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Thanks for the reply and the suggestion. I will look into sub-steps and see what happens 🙂

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**Author:** ![PresumptivePanda](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/presumptivepanda/32/1194593_2.png) [@PresumptivePanda](https://forums.unrealengine.com/u/PresumptivePanda)\
**Post date:** [November 24, 2022, 11:46pm UTC](https://forums.unrealengine.com/t/cant-get-forward-velocity-multiplied-with-delta-seconds-consistent/689744/5 "2022-11-24T23:46:16Z")

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This topic has been moved from **International** to **Programming & Scripting: Blueprint**.

When posting, please review the categories to ensure your topic is posted in the most relevant space. Hopefully, this category change helps you or other devs with similar questions.

Happy developing! 🙂