ArduKinematics

A Modular, High-Performance Inverse Kinematics Library for ArduPilot

ArduKinematics is a lightweight Lua-based framework designed to provide standardized manipulator control for the ArduPilot ecosystem. By abstracting complex trigonometric and iterative solvers, it enables N-DOF serial manipulators (humanoid limbs, rover arms) to be commanded via simple Cartesian $(x, y, z)$ coordinates.

Key Features

• Heuristic Solver Engine: Implementation of the FABRIK (Forward And Backward Reaching Inverse Kinematics) algorithm, optimized for low-latency execution on flight controller hardware.
• Coordinate Frame Standardization: Built on Denavit-Hartenberg (DH) Parameters, allowing the library to be reconfigured for any arm geometry via a simple config table.
• pi.FO (Field Operator) Reference: A 5-DOF high-fidelity simulation model used as the "Golden Standard" for library validation.
• "Fusion-to-Flight" Pipeline: A documented workflow for converting Fusion 360 CAD designs into Gazebo Harmonic-ready SDF models.
• Stability Aware: Built-in hooks for EKF3 tilt-compensation to protect the vehicle's Center of Gravity (CoG) during arm extension.
• Fusion Demo

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Installation & Setup

1. Prerequisites

• ArduPilot SITL (Ubuntu 22.04 / WSL2 recommended)
• Gazebo Harmonic
• ArduPilot-Gazebo Plugin

2. Environment Configuration

Add the resource path to your ~/.bashrc:

export GZ_SIM_RESOURCE_PATH=$GZ_SIM_RESOURCE_PATH:~/ArduKinematics/simulation/models

3. Launching the SITL Environment

Terminal 1 (Gazebo):

gz sim -v4 -r pifo_test.world

Terminal 2 (ArduPilot):

sim_vehicle.py -v Rover -f gazebo-pifo --model gazebo-pifo -I0

Project Roadmap

• Mathematical Foundation (DH-Parameters & Primer)
• Current Phase: URDF/SDF Model Finalization (Gazebo Harmonic)
• Core FABRIK Solver Implementation (Lua)
• MAVLink Telemetry Integration (NAMED_VALUE_FLOAT)