Construction robotics · RA-L 2026

Tripody A lightweight construction robot
for ceiling drilling.

A 33 kg tripod construction robot for overhead tasks. Three extending legs position a drilling tool above a compact wheeled base.

arXiv Read the preprint IEEE Xplore Read the publication

Accepted in IEEE Robotics and Automation Letters, July 2026.

Tripody tripod construction robot in three height configurations for ceiling drilling, with close-ups of the tool and wheeled base.
Three views of Tripody, from compact transport to full extension. Insets show the drilling tool and wheeled base.
Explore the robot
System mass
33 kg
Platform height
1.7–3.4 m
Continuous payload
32 kg

The platform

A tripod robot
for construction.

Tripody is a tripod robot whose three extending legs support and position a shared tool platform. This parallel mechanism provides three degrees of freedom, vertical reach, and a modular tool interface for overhead construction work.

Universal base joints increase resistance to twisting. Small structural deflections accommodate the mechanism’s intentional overconstraint.

The prototype prioritizes reach, stiffness, and portability within a limited horizontal workspace. The mechanical design and operating limits are documented in the paper.

Experimental results

Ceiling drilling,
put to the test.

As a ceiling construction robot, Tripody addresses a demanding application of construction robotics: drilling overhead while maintaining accurate positioning and stability under tool loads. The study evaluates positioning and drilling separately.

Overhead drilling

15 holes

Drilled in open loop at 3.2 m. Maximum relative hole-position error: 4.5 mm after rigid alignment.

Drilling experiment

This drilling study establishes task feasibility; it does not measure absolute hole accuracy in a building coordinate frame.

Publication

Read the full research.

Tripody: An Overconstrained 3-SPR-like Parallel Robot for High-Reach Construction Tasks

Julien Kindle, Jakub Raczy, Riccardo Balbi, Andrea Alessandretti, Cesar Cadena, and Marco Hutter.

IEEE Robotics and Automation Letters, vol. 11, no. 9, pp. 10497–10504, 2026.

DOI: 10.1109/LRA.2026.3713724

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