<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[Disabling PX4 autopilot and directly command 4x1 thrust and torque for low-level control]]></title><description><![CDATA[<p dir="auto">Hi ModalAI team, I am working on a project that involves developing an end-to-end neural network-based control policy for a quadrotor. For this, I would like to bypass the PX4 autopilot and directly control the drone at the low level using a 4x1 vector of thrust and torque (roll, pitch, yaw) commands, similar to what is used in 12D system models.</p>
<p dir="auto">My goal is to retain the VOXL infrastructure, especially for reading from onboard services like custom neural network outputs through the voxl-tflite-server pipes and using the existing sensor and system services. However, I would like to disable PX4's control stack and instead send raw actuator commands directly from my control policy.</p>
<p dir="auto">Could you clarify whether this type of low-level control is supported through VOXL’s existing service architecture? If so, do I need to implement my control policy in C++, or is it also feasible to use Python for sending these thrust and torque commands at a low enough latency for closed-loop flight? Any guidance on how to interface with the motor outputs or appropriate service pipes to do this would be greatly appreciated. Thank you.</p>
]]></description><link>https://forum.modalai.com/topic/4587/disabling-px4-autopilot-and-directly-command-4x1-thrust-and-torque-for-low-level-control</link><generator>RSS for Node</generator><lastBuildDate>Fri, 09 Oct 2026 07:57:43 GMT</lastBuildDate><atom:link href="https://forum.modalai.com/topic/4587.rss" rel="self" type="application/rss+xml"/><pubDate>Sat, 12 Jul 2025 00:17:41 GMT</pubDate><ttl>60</ttl><item><title><![CDATA[Reply to Disabling PX4 autopilot and directly command 4x1 thrust and torque for low-level control on Sat, 12 Jul 2025 23:45:20 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/user/eric-katzfey" aria-label="Profile: Eric-Katzfey">@<bdi>Eric-Katzfey</bdi></a> I see. Thanks for the response.</p>
]]></description><link>https://forum.modalai.com/post/23055</link><guid isPermaLink="true">https://forum.modalai.com/post/23055</guid><dc:creator><![CDATA[Ege Yüceel]]></dc:creator><pubDate>Sat, 12 Jul 2025 23:45:20 GMT</pubDate></item><item><title><![CDATA[Reply to Disabling PX4 autopilot and directly command 4x1 thrust and torque for low-level control on Sat, 12 Jul 2025 02:42:46 GMT]]></title><description><![CDATA[<p dir="auto"><a class="plugin-mentions-user plugin-mentions-a" href="/user/ege-y%C3%BCceel" aria-label="Profile: Ege-Yüceel">@<bdi>Ege-Yüceel</bdi></a> This is definitely not supported by ModalAI. However, a sophisticated developer has access to enough documentation and source code that it is possible to make that work.</p>
]]></description><link>https://forum.modalai.com/post/23050</link><guid isPermaLink="true">https://forum.modalai.com/post/23050</guid><dc:creator><![CDATA[Eric Katzfey]]></dc:creator><pubDate>Sat, 12 Jul 2025 02:42:46 GMT</pubDate></item></channel></rss>