Interstellar fan Charlie Diaz would argue that TARS is one of the most iconic movie robots in the history of cinema. He was so inspired by its design that he set about making his own mini replica.

TARS is one of four former U.S. Marine Corps tactical robots. It was programmed to be the witty one in the foursome, making it a well suited, if sassy, companion for the humans in the crew.

Iconic design

It may look like four shiny cuboids just trotting along, but in his project post, Charlie explains the secret genius behind the seemingly simple design:

“At a glance, TARS appears to be a rather simple walking robot, consisting of only two legs, each with a single joint. Upon closer inspection one can find a hidden translational degree of freedom near the leg joints, responsible for creating clearance for the legs as they rotate past the center torso, or vice versa.”

It’s this element that allows the robot to propel itself forward without getting stuck on its own feet.

While the real TARS can separate its central torso block into two pieces, Charlie kept his replicas more simple, featuring just the one torso piece supported by two legs.

Replica hardware

• Raspberry Pi 3 Model B
• Adafruit servo driver
• Four high-torque servos (one to rotate each leg, and two to lift the torso)
• 5″ touchscreen monitor
• 8BitDo Bluetooth remote
• LiPo battery

Alterations

Version three (pictured below) appears to have a more matte finish than Charlie’s first attempt. The first one has sheet aluminium wrapped around the 3D-printed parts, which he notes were very heavy, making it difficult for the robot to walk very far. Version one also housed heavy NiMH batteries, which were swapped out for a lighter LiPo battery pack.

This latest version has dual robotic arms which it can use to interact with its environment. No word on how many more iterations Charlie has in mind, but he has made all the CAD files and code available to anyone else who wants to build their own replica.

Full-size fun

Charlie is so serious about this TARS business that he also built a full-sized replica. That is quite the Halloween costume.

The original robots were operated on the film set just like Charlie is puppeteering his full-size replica above. Fun fact: the actor Bill Irwin, who voiced TARS, physically operated the 200-pound robot throughout filming. He also happens to play Mr. Noodle on Sesame Street. We call that range, dahling.