C-Quad: A miniature, foldable quadruped with C-shaped compliant legs

Abstract

C-Quad is an origami-inspired, foldable, miniature robot whose legs and body are all machined from one PET sheet each. The already famous compliant legs are modified such that they can be manufactured from a flat PET sheet and folded into the C-shape wanted. The compliant legs enable the miniature robot to run fast and scale obstacles with ease due to the geometry of the legs. C-Quad has four legs that are manufactured separately from the main body frame, which is also manufactured from a single PET sheet. All of its legs are actuated individually with a total of four DC motors. Despite the thin PET film, the structural rigidity and robustness of the body frame is increased by using specialized folds and locks. The manufacturing and assembly of the robot takes approximately 2.5 hours. C-Quad carries a battery, an Arduino Pro Micro control board, a bluetooth communication module, custom made encoders and commercially available IR sensors for motor speed control and motor drivers, all of which weighs 38 grams. By using very simple control strategies, it can achieve the speed of 2.7 Bodylengths/sec, can perform in-place turns and can climb over obstacles more than half of its height.

Design, Fabrication, and Locomotion Analysis of an Untethered Miniature Soft Quadruped, SQuad

“…Its rounded shape provides the distribution of stresses upon impact. Last but not least, such a leg design has previously been shown to work on miniature legged robots [16], [18].…”

“…The robot that is desired to be created does not exist in literature except for few examples [9] that are in relatively larger scales. Some robots are made out of hard materials with very similar designs [16] but their behavior is significantly different. This difference is our main motivation, as we want to investigate if robots that are almost identical in design but different in material are behaving similarly.…”