From 8b5fd065741baf3ae96ec0ba00960732d5d32ceb Mon Sep 17 00:00:00 2001
From: Kelly Guo <kellyg@nvidia.com>
Date: Mon, 13 Jan 2025 20:05:55 -0500
Subject: [PATCH] Fixes documentation error for PD Actuator (#1668)

# Description

There was a mismatch in the implementation of the IdealPDActuator code
and the equation provided in the actuators docs. This change fixes the
ordering of parameters in the docs to match the implementation in code.

Fixes #1643

## Type of change

- This change requires a documentation update

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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---
 docs/source/overview/core-concepts/actuators.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/source/overview/core-concepts/actuators.rst b/docs/source/overview/core-concepts/actuators.rst
index 15bde0cdb8..b3085b31c2 100644
--- a/docs/source/overview/core-concepts/actuators.rst
+++ b/docs/source/overview/core-concepts/actuators.rst
@@ -34,7 +34,7 @@ maximum effort:
 
 .. math::
 
-    \tau_{j, computed} & = k_p * (q - q_{des}) + k_d * (\dot{q} - \dot{q}_{des}) + \tau_{ff} \\
+    \tau_{j, computed} & = k_p * (q_{des} - q) + k_d * (\dot{q}_{des} - \dot{q}) + \tau_{ff} \\
     \tau_{j, applied} & = clip(\tau_{computed}, -\tau_{j, max}, \tau_{j, max})