USERKINS(9)

💖 USERKINS(9) — bestie's guide to the HAL Component 💖

okay so. this is a page from the HAL Component manual section, and it's about userkins — which is literally just a template you can take and make your own. it's giving "starter pack" energy. let's get into it 🎀

---

✨ NAME ✨

userkins — the template for user-built kinematics, periodt 💅

---

🌸 SYNOPSIS 🌸

loadrt userkins [count=N|names=name1[,name2...]]

---

🦋 DESCRIPTION 🦋

the userkins.comp file is a whole template for making kinematics that you can user-build using halcompile. no cap. 🔥

if you don't touch it at all, the unmodified userkins component still works as a kinematics file for a machine with identity kinematics — that's an xyz machine using 3 joints (aka motors). slay.

💜 USAGE 💜

1. copy the userkins.comp file into a directory you own (mydir).

note bestie: you can download userkins.comp from https://github.com/LinuxCNC/linuxcnc/raw/2.8/src/hal/components/userkins.comp where '2.8' is the branch name (use 'master' for the master branch).

for a RIP (run-in-place) build, the file lives in the git tree like this:

src/hal/components/userkins.comp

2. edit the functions kinematicsForward() and kinematicsInverse() however you need to ✏️
3. if you need them, add hal pins — just follow the examples in the template code 🫶
4. build and install the component using halcompile:

$ cd mydir
$ [sudo] halcompile --install userkins.comp
# Note:
#      sudo is required when using a deb install
#      sudo is not required for run-in-place builds
# $ man halcompile for more info

5. specify userkins in an ini file like this:

[KINS]
KINEMATICS=userkins
JOINTS=3
# the number of JOINTS must agree with the
# number of joints used in your modified userkins.comp

6. note: the manpage for userkins is not updated by halcompile --install 🙈
7. want a different component name? rename the file (example: mykins.comp) and then change all instances of 'userkins' to 'mykins' 🔁

⭐ NOTES ⭐

1. the fpin pin is included just to satisfy the requirements of the halcompile utility, but heads up — it is not accessible to kinematics functions.
2. hal pins and parameters that you need inside kinematics functions (kinematicsForward(), kinematicsInverse()) have to be set up in a function (userkins_setup()) that gets invoked by the initial motion module call to kinematicsType().

---

🔥 FUNCTIONS 🔥

• userkins.N.fdemo — this one requires a floating-point thread ⚠️

---

🌈 PINS 🌈

• userkins.N.fpin s32 out (default: 0) — a pin that demonstrates use of a conventional (non-kinematics) function fdemo ✨

---

👑 AUTHOR 👑

Dewey Garrett

---

💀 LICENSE 💀

GPL

---

okay that's the whole thing, you ate it up, you're the main character of HAL now 💖 this was USERKINS(9) from the HAL Component manual, served to you by LinuxCNC Documentation on 2026-03-17 — ily, go build something iconic 🦋✨