Skip to content
RobothecaBeta

Photo and 3D model

TipToe, photo from its repository
Photo@jiz322 (opens in a new tab)CC-BY-4.0source file (opens in a new tab)
Try it in the browser

3D preview converted from github.com/jiz322/tiptoe-biped at c91dedb, under CC-BY-4.0. View the original files from GitHub (3.7 MB) (opens in a new tab)

Open source · free files

TipToe

Other

A 6-DOF point-foot biped with no ankles, built from printed parts and RobStride actuators, trained with PPO in Isaac Lab to stand up, step and sit on hardware.

Project information

Buildability
60/100Buildable with some effort
Estimated cost
¥5,700approx. €762 (ECB rate, 5 Nov 2026)18 parts have no listed price; the real cost may be higher.As stated by the creator.
Level
Advanced
Parts
18 lines
Tools
3D printer, soldering iron
Hardware license
CC-BY-4.0 (opens in a new tab)
Software license
MIT (opens in a new tab)
Commercial use
Allowed
Degrees of freedom
6

Work in progress: the creator is still working on it.

This repository contains executable files that Robotheca doesn't check. Only run them if you trust the creator.

Which files (72 scripts)
Download the files, free (.zip at the pinned commit)Fork on GitHub (opens in a new tab)

Suggested by Robotheca, created by @jiz322 (opens in a new tab), from github.com/jiz322/tiptoe-biped (opens in a new tab), pinned to commit c91dedb (opens in a new tab). You buy the parts yourself; Robotheca doesn't sell robots.

What to buy

18 lines, read from hardware/BOM.md at c91dedb
Export CSV (parts list)

18 of 18 parts shown

  • Priced lines
  • 4 599RobStride RS01––
  • 2 299RobStride EL05––
  • 1 724Raspberry Pi 5––
  • 1 289microSD card––
  • 1 254WHEELTEC H30 IMU––
  • 1 40MCP2518FD SPI CAN module––
  • 2 3814S 6500 mAh semi-solid LiPo––
  • 1 98Matek PDB-HEX––
  • 2 140RA5008 crossed-roller bearing (hip roll)––
  • 2 30HTD 5M timing belt––
  • –3D-print filament––
  • –Screws, nuts, heat-set inserts––
  • Unpriced lines — TBD
  • 1ELRS receiver––
  • 2Pulleys 22T and 30T, HTD 5M––
  • –Other bearings––
  • 2Steel parts––
  • 2Ball feet––
  • –Wiring––

18 of 18 needed parts have no price in the source, so there is no parts total.

Why it scores 60

It measures the published files, not the robot · How we score

60/100

Buildable with some effort

How complete the published files are for rebuilding this robot, measured by Robotheca at commit c91dedb. It isn't a rating of the robot.

  1. 13D and CAD filesNo printable parts or CAD files.Most points to gain: Add the parts to print (STL or 3MF files). Add the CAD source (STEP, or the CAD program's own files) so people can change the design.0/20
  2. 2Robot descriptionA URDF with all its mesh files.15/15
  3. 3Parts list18 lines: 0 with a price, 0 with a shop link.Add prices to 18 lines. Add shop links to 18 lines.5/20
  4. 4SoftwareCode in this repository, instructions to install or run it.Say which software framework it uses (ROS 2, LeRobot, Arduino…).10/15
  5. 5DocumentationREADME of 15,328 characters with 6 pictures; 6 build steps.15/15
  6. 6Simulation5 simulation files (MuJoCo, Gazebo, Webots or Isaac).5/5
  7. 7LicensesHardware: CC-BY-4.0; software: MIT.10/10

Build it

The creator's 6 steps, each linked to its instructions
  1. Print the 24 structural parts from the MakerWorld listing or STL files
  2. Assemble the legs and hip bodies per hardware/ASSEMBLY.md
  3. Wire the motors, CAN board, IMU and power distribution board
  4. Set up the Raspberry Pi 5 with CAN bring-up and the control stack
  5. Zero the motors and verify all six reply with test_motors.py
  6. Run the released policy with balance_log.py

The guide appears here as you scroll.

Guide by @jiz322 (README.md), under CC-BY-4.0 (hardware) and MIT (software).

More guides

Wiring and electronics

Notes written by Robotheca from the project's documents, not by its creator

Main parts: Robotheca's summary

  • Raspberry Pi 5 running the policy and control loop.
  • Four RobStride RS01 and two RobStride EL05 quasi-direct-drive actuators.
  • WHEELTEC H30 IMU on the torso top board, read over UART at 400 Hz.
  • MCP2518FD SPI CAN module connecting the Pi to the motors.
  • ELRS receiver for radio control via CRSF.
  • Two 4S 6500 mAh LiPo packs and a Matek PDB-HEX power distribution board.

Connections: Robotheca's summary

  • All six motors share one 1 Mbps classic CAN bus with 120 Ohm termination at both ends.
  • The MCP2518FD board attaches to the Pi's SPI interface using the mcp251xfd overlay, appearing as can0.
  • The IMU connects to the torso top board over UART at 460800 baud and is mounted rotated 180 degrees about z.
  • The PDB-HEX BEC feeds the Pi and the IMU 5 V rail from the battery packs.
  • Each motor must be assigned its own host ID so replies do not collide.
  • The ELRS receiver speaks CRSF to the Pi on /dev/ttyAMA2 at 420000 baud.

Cables and connectors

From the parts list.

  • Wiring

What it can do: Robotheca's summary

Written by Robotheca from the project's documents, not by its creator
  • Stands up from a crouch, steps in place, and sits back down on command (hardware flight of 2026-10-11).
  • Point-foot 6-DOF biped with no ankles, balancing by reactive stepping under a PPO policy running at 100 Hz on the Raspberry Pi 5.
  • Stepping in place lasted 18.9 s and 43.6 s, both ended by a commanded sit.
  • Does not currently stand still; holds a roughly 2.5 Hz limit cycle while balancing.
  • Currently not flyable: the right knee belt broke and the replacement design is not yet built.

Works with AI

Found by Robotheca in the project's files at commit c91dedb, its robot.yaml and Robotheca's notes on its documents. Never guessed; Robotheca doesn't run the code.

Software

Framework
Not stated
Languages
Python, Shell
License
MIT

Robotheca doesn't review code. Read it before running it.

How to run it: Robotheca's summary

Written by Robotheca from the project's documents, not by its creator.

  1. 1Set each RobStride motor to MIT mode with the vendor tool, using IDs 101 to 106.
  2. 2Assign distinct host IDs to the motors with set_host_ids.py.
  3. 3Bring up the CAN interface with setup_can0.sh on each boot.
  4. 4Verify all six motors reply with test_motors.py --no-zero.
  5. 5Zero the knee joints at the crawl pose using setzero_crawl.py before each session.
  6. 6Run balance_log.py with the released policy r1r_3150.pt and the +0.089 pitch trim to reproduce the September behaviour, using the keyboard to select groups, adjust gains and hand over to the policy.

Software that runs on this robot

No software from Robotheca's catalogue found in this robot's files yet. Links come from its robot.yaml, its dependency files read as text, or Robotheca's editors.

The code

Free files

Browse all files

Every file of the project, at commit c91dedb.

Community

Questions and improvements go to the creator's repository.

Add a badge to your README

For the creator: two badges that link back here. The second always shows this page's current label and score.

Listed on RobothecaRobotheca buildability

Markdown (one click selects it)

[![Listed on Robotheca](https://robotheca.org/robots/tiptoe/badge.svg)](https://robotheca.org/robots/tiptoe)
[![Robotheca buildability](https://robotheca.org/robots/tiptoe/score.svg)](https://robotheca.org/robots/tiptoe)

Other other robots

All 100 other robots
  • Ready to build

    Open source · free files

    Koriobots

    Other · Intermediate

    Score
    Buildability 98 out of 100
    Cost
    $972.06≈ €866
  • Ready to build

    Open source · free files

    AmazingHand

    Other · Intermediate

    Score
    Buildability 88 out of 100
    Cost
    under €200
  • Ready to build

    Open source · free files

    DigiArm Prosthetic Hand

    Other · Advanced

    Score
    Buildability 85 out of 100
    Cost
    $250≈ €223
  • 3D render

    Open source · free files

    FloatingFace

    Other · Advanced

    Score
    Buildability 100 out of 100
    Cost
    $328.47≈ €293

≈ € values are approximate, converted at the ECB euro reference rate of 5 Nov 2026. The creator's original price always comes first.