Tsogt (Todd) Enkhbat -- Physics, spacecraft engineering, and space infrastructure

3 DOF
platform motion: 3 × NEMA 17
stepper-motor actuation

A satellite’s solar panel needs to face the light while the spacecraft’s orientation changes. HALO explores a compact parallel mechanism for that problem: three arms supporting a platform that can tip, tilt, and move vertically. The physical prototype combines Onshape geometry, iterated printed parts, assembled hardware, and wired motors and light sensors.

Three-arm linkage and printed joints

Three motor-driven arms support the same platform. Moving their attachment points changes the platform’s tip, tilt, and height. The links need enough clearance to move without colliding, while the joints must fit the printed mounts and fasteners.

The assembly was modeled in Onshape, with PLA parts iterated before assembly. The photographs show the motor mounts, paired links, and platform attachments; the CAD view shows how those components fit together.

HALO’s assembled three-arm mechanism — printed links, motor mounts, and moving platform

Motor drivers, sensing, and bench integration

The prototype uses three NEMA 17 stepper motors, A4988 drivers, an Arduino, and light sensors. The motors and sensors are wired into the assembled mechanism; the breadboards and bench supply are shown alongside the hardware.

The video records the assembled prototype on the bench. Firmware remained a blocker before powered tracking, so the documented result is an assembled and wired mechanism, with closed-loop control still to validate.

On the bench — original prototype footage, with audio removed.

Arduino, breadboard wiring, and bench power equipment used during integration

The assembled platform alongside its bench electronics

Assembly work: motor hardware, fasteners, and hand tools

Ring gimbal and lab presentation

The larger test rig suspends an assembly inside nested rings, with an aluminum frame supporting the outer axis. The lab photograph shows the rig’s physical size and mounting arrangement.

The presentation describes an attitude-control test platform using fan actuation, an IMU, and a 12 V power supply. The proposed test sequence isolates individual axes before attempting coupled motion.

The larger ring gimbal on the laboratory bench

Presenting the gimbal hardware and test context in the lab

Explore the HALO geometry in 3D ↗

A reconstruction of the three-arm assembly shown in the project CAD. Separate the components to inspect the geometry; this is not a simulation of measured actuation.

Top view of the printed platform and its three supporting arms

Original design rendering of the HALO mechanism

Context & sources

Original project photographs, descriptions, and records are collected in this archive.

3D study: Illustrative reconstruction of the supplied linkage CAD; powered tracking remains unvalidated.