Ik Geo

This is a Rust implementation of the analytic inverse kinematics algorithms found in the IK-Geo paper. This implemenation has been adapted from the original Rust implementation by RPI Robotics.

Usage

To use this package, you either need to choose a an implemented model by name, or specify the kinematics as a Product of Exponentials and select the appropriate problem decomposition.

// Only need to import the one you are using
use ik_geo::robot::{
    spherical, spherical_two_parallel, spherical_two_intersecting, three_parallel_two_intersecting, three_parallel, two_parallel, 
    two_intersecting, gen_six_dof
}
use ik_geo::robot::{
    ur5, irb6640, three_parallel_bot, two_parallel_bot, spherical_bot
}

fn main() {
    let robot = ur5();

    let R: Matrix3<f64> = ...
    let t: Vector3<f64> = ...

    // Solutions is a list of IK solutions
    // and whether they are least squares approximations.
    // Depending on the specific decomposition, a least squares solution might not be available.
    let solns = robot.ik(R, t);

    for (q, is_ls) in solns {
        if !is_ls {
            // This is an exact solution
        } else {
            // This one is close, but not exact
        }
    }
}

Performance

While this implementation can be used on a wide range of manipulators, it performs much better on when the solution can be found entirely analytically. The following table shows which method is used for each type of kinematics:

Solution Type	Robot Kinematic Family	Example
Closed-form	Spherical joint	Franka Production 3, fixed $q_5$
	and two intersecting axes	KUKA LBR iiwa 7 R800 , fixed $q_3$
	and two parallel axes	ABB IRB 6640
	Three parallel axes	N/A
	and two intersecting axes	Universal Robots UR5
	and two parallel axes	N/A
1D search	Two intersecting axes	Kassow Robots KR810, fixed $q_7$
	and two intersecting axes	FANUC CRX-10iA/L
	and two parallel axes	Kawasaki KJ125
	Two parallel axes	N/A
	and two parallel axes	N/A
	Two intersecting axes $k, k+2$	ABB YuMi, fixed $q_3$
	and two intersecting axes	RRC K-1207i, fixed $q_6$
	and two parallel axes	N/A
2D search	General 6R	Kassow Robots KR810, fixed $q_6$

Testing

Correctness Tests

$ cargo test --release

For diagnostic info:

$ cargo test --release -- --nocapture