skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Attention:

The NSF Public Access Repository (PAR) system and access will be unavailable from 10:00 PM ET on Friday, February 6 until 10:00 AM ET on Saturday, February 7 due to maintenance. We apologize for the inconvenience.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: A Multimodal Climbing-Swimming Soft Robotic Lamprey
Here, we present a multimodal, lamprey-inspired, 3D printed soft fluidic robot/actuator based on an antagonistic pneunet architecture. The Pacific Lamprey is a unique fish which is able to climb wetted vertical surfaces using its suction-cup mouth and snake-like morphology. The continuum structure of these fish lends itself to soft robots, given their ability to form continuous bends. Additionally, the high gravimetric and volumetric power density attainable by soft actuators make them good candidates for climbing robots. Fluidic soft robots are often limited in the forces they can exert due to limitations on their actuation pressure. This actuator is able to operate at relatively high pressures (for soft robots) of 756 kPa (95 psig) with a −3 dB bandwidth of 2.23 Hz to climb at rates exceeding 18 cm/s. The robot is capable of progression on a vertical surface using a compliant microspine attachment as the functional equivalent of the lamprey’s more complex suction-cup mouth. The paper also presents the details of the 3D-printed manufacturing of this actuator/robot.  more » « less
Award ID(s):
1935278
PAR ID:
10385204
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
BATH/ASME 2022 Symposium on Fluid Power and Motion Control
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. (, IEEE International Conference on Soft Robotics)
    Soft robots struggle with terrestrial locomotion due to their inherent lack of rigidity, specifically along axes not in line with the direction of actuation (side loads). We present a method for improved stiffness in a 3D printed, tendon-driven soft actuator. We show, both mathematically and experimentally, that our method leads to improved stiffness to these side loads. Additionally, we demonstrate the use of complex tendon routing schemes to achieve various trajectories with a single actuator morphology. Finally, we demonstrate that these two tendon routing strategies lead to improved locomotion speed and gait efficiency in a 3- legged, 3D printed, soft robot. 
    more » « less
  2. ; ; ; ; ; (, IEEE)
    Existing fluidic soft logic gates for controlling soft robots typically depend on labor-intensive manual fabrication or costly printing methods. In our research, we utilize Fused Deposition Modeling to create fully 3D-printed fluidic logic gates, fabricating a valve from thermoplastic polyurethane. We investigate the 3D printing of tubing and introduce a novel extrusion nozzle for tubing production. Our approach significantly reduces the production time for soft fluidic valves from 27 hours using replica molding to 3 hours with FDM printing. We apply our 3D-printed valve to develop optimized XOR gates and D-latch circuits, presenting a rapid and cost- effective fabrication method for fluidic logic gates that aims to make fluidic circuitry more accessible to the soft robotics community. 
    more » « less
  3. ; ; (, Bioinspiration & Biomimetics)
    Abstract Snakes and their bio-inspired robot counterparts have demonstrated locomotion on a wide range of terrains. However, dynamic vertical climbing is one locomotion strategy that has received little attention in the existing snake robotics literature. We demonstrate a new scansorial gait and robot inspired by the locomotion of the Pacific lamprey. This new gait allows a robot to steer while climbing on flat, near-vertical surfaces. A reduced-order model is developed and used to explore the relationship between body actuation and the vertical and lateral motions of the robot. Trident, the new wall climbing lamprey-inspired robot, demonstrates dynamic climbing on a flat near vertical carpeted wall with a peak net vertical stride displacement of 4.1 cm per step. Actuating at 1.3 Hz, Trident attains a vertical climbing speed of 4.8 cm s−1(0.09 Bl s−1) at specific resistance of 8.3. Trident can also traverse laterally at 9 cm s−1(0.17 Bl s−1). Moreover, Trident is able to make 14% longer strides than the Pacific lamprey when climbing vertically. The computational and experimental results demonstrate that a lamprey-inspired climbing gait coupled with appropriate attachment is a useful climbing strategy for snake robots climbing near vertical surfaces with limited push points. 
    more » « less
  4. ; ; ; ; ; ; ; ; (, Science Advances)
    null (Ed.)
    The emergence of soft robots has presented new challenges associated with controlling the underlying fluidics of such systems. Here, we introduce a strategy for additively manufacturing unified soft robots comprising fully integrated fluidic circuitry in a single print run via PolyJet three-dimensional (3D) printing. We explore the efficacy of this approach for soft robots designed to leverage novel 3D fluidic circuit elements—e.g., fluidic diodes, “normally closed” transistors, and “normally open” transistors with geometrically tunable pressure-gain functionalities—to operate in response to fluidic analogs of conventional electronic signals, including constant-flow [“direct current (DC)”], “alternating current (AC)”–inspired, and preprogrammed aperiodic (“variable current”) input conditions. By enabling fully integrated soft robotic entities (composed of soft actuators, fluidic circuitry, and body features) to be rapidly disseminated, modified on demand, and 3D-printed in a single run, the presented design and additive manufacturing strategy offers unique promise to catalyze new classes of soft robots. 
    more » « less
  5. ; ; ; ; (, Advanced Intelligent Systems)
    Perching significantly enhances the energy efficiency and operational versatility of aerial robots. This article introduces a passive and tunable perching mechanism designed for smooth surfaces. The design features a bistable mechanism (BM) with a soft suction cup, augmented by two sets of shape memory alloy (SMA) actuators for active tuning. The BM enables rapid attachment upon surface contact. A set of SMA wires can increase the BM's triggering force to handle high contact speeds, while a set of SMA springs attached to the suction cup's edges can pull the cup to handle orientation misalignment. Experiments are conducted to characterize how the SMA actuators influence the BM's triggering force and the suction cup's displacement under continuous steady‐state low‐voltage heating. Additional experiments demonstrate fast tuning using momentary high‐voltage heating of the SMA actuators to enhance energy efficiency. The mechanism enables successful perching on smooth surfaces and adapt to varying contact speeds and misalignments when properly tuned for three scenarios: pendulum‐based perching, ground perching, and ceiling perching. With its tuning capability, the perching mechanism can alleviate the need for precise motion control for an aerial robot during perching, expanding the applications of aerial robots in areas like environmental monitoring or infrastructure inspection. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Text Encoded Conversion
  • XML
  • Save / Share this Record
  • Send to Email