Open Ro ACH

Updated 7th March 2019 by Liyu Wang.

Project Leader:
Dr. Liyu Wang

2018: Gustavo Correa, Dantong(Claire) Dong, Brendan Hogg, Yunfan(Daniel) Hua, Yuxiang Yang, Shuo Yang
2017: Raghav Anand, Patrick Chao, Eric Eom, Andrew Fearing, John Lin, Simin Liu, Grant Walton, Yuxiang Yang
2016 and before: Galen Savidge, Dr. Duncan Haldane, Jeffery Kurohara


The OpenRoACH is a 15-cm long and 200-gram hexapod crawling robot. It is the smallest legged robot running the Robot Operating System (ROS) onboard. With two Pololu metal gear DC motors and a Beagle Bone Blue board, OpenRoACH is underactuated, affordable ($150), and fully open-source. Fabrication is straightforward with bench-top fast-prototyping machines such as a laser cutter and a 3D printer. Assembly can be done manually with hot glue, super glue and screws by one person in two hours.
Key features include:

  • dynamical walking and running capabilities on multiple surfaces and terrain.
  • multi-model sensory capacity with cameras, colour tracking sensors, linescan sensors, gyroscopes, accelerometers, and Beacon sensors.
  • durable with 24-hour continuous burn-in test walking on a tread mill.
  • 200 gram payload capacity dynamically.
  • onboard ROS, optional mbed microcontroller

The present complete version for mechanical design is version 1.2.

Publication and Video

Wang, L., Yang, Y., Correa, G., Karydis, K., and Fearing, R. S. (2019) OpenRoACH: A durable open-source hexapedal platform with onboard Robot Operating System (ROS). In Proceedings of the 2019 IEEE International Conference on Robotics and Automation (ICRA), 20-24 May 2019, Montreal, Canada. In press. PrePrint

A video of OpenRoACH

Mechanical Design and Fabrication

Present version (v1.2) CAD files
Fabrication and Assembly Instructions


Line scanner sensor

Line Scanner

Freescale linescan sensor reading app

Proximity sensor and electromagnet

Light Sensor and Electromagnet

Electronics and Microcontrollers

PCB carrier board

Locomotion Control

Color Object following control based on Pixy Sensor----100% CAMERA (If you have any question, E-mail me: YangShuo960502 at

Line following control based on a Freescale linescan sensor

Direction Control based on a pair of Pololu beacons(Final Updated)

Line following based on Freescale linescan sensor and accelerameter

Ros Integration

See for details of setup.

Cost of Parts

Link to the Document

Version history

September 2017-September 2018
ROS enabled with Beagle Bone Blue, reduced electronics mass to 40 g.
Hip flexure shape modified.
Side shaft-tightening-screw hole added to pulley-flange.

July 2017-August 2017
Chassis middle lowered to accommodate electronics.
Tested higher speed motors, 50:1 Micro Metal Gearmotor HP.
v1.1 CAD files

June 2017-July 2017
Two-piece 3D-printable pulleys.
A 3D-printable motor mounting base.
Reuse the initial motor driver on Zumy board, remove many wiring cables.
Legs from C-shape to O-shape.

February 2017-May 2017
Chassis made from poster board, nylon and PET.
Dual shafts, 298:1 Micro Metal Gearmotor HP, three-piece 3D-printable pulleys, timing belts, and a laser cut motor mounting base.
Self-contained with 22-gram battery.

November 2016 - January 2017
Chassis made from PET and nylon.
Leg transmission bar made from Delrin.
Self-contained with onboard Zumy board, Dual MC33926 Motor Driver Carrier, 50-gram battery, and line scanner sensor.
Realized path following with ∞ trajectory three times.

Before October 2016
A 1.5x scaled VelociRoACH chassis made from poster board and nylon with a Tamiya twin motor gearbox.
AutoCAD drawings, assembly guide, and bill of materials for v0.1 are available on Github.\\