Modular, Vacuum-Powered Robot Adds Versatility to Soft Robotics

Researchers introduce a modular robot powered by vacuums instead of pressurized air.

Researchers at the Swiss Federal Institute of Technology in Lausanne (EFPL) recently produced a paper in the journal Science Robotics on a new approach to modular soft robots, a first in the field in its combination of modular functionality and use of a V-SPA (vacuum-powered pneumatic actuator). Though soft robotics have seen an increase in popularity, the "plug-and-play" ability to lego pieces together is a new one.

This particular robot contains three pneumatic pumps that can be stacked together and expand and collapse to allow a change in direction. Once they’re in place, they draw from the same power source and utilize the same control system. By using air pressure to power artificial muscles, many robots overexpand and create mechanical problems. Powered by a vacuum instead of through pressurized air, they work through contraction instead of expansion, in the same way as human muscles.

Image courtesy of the Swiss Federal Institute of Technology.

The paper's authors are Matthew Robertson and Jamie Paik, a doctoral assistant and tenure-track assistant professor, respectively. Both hail from the EPFL's Reconfigurable Robotics 
Laboratory (RRL), which is dedicated to researching the most promising designs and materials for reconfigurable soft robotics. Their goal is to produce robotics that can serve in applications from the medical field to wearables.

Why This Is Important

A modular robot has the potential to really change the industry because of its versatility. The Verge points out that it is easily modified by attaching a grasping tool to create a robotic arm, adding more modules to increase size, stacking together to create a snake-like motion, or even adding suction cups to provide for window climbing.

In an interview with New Scientist, Jamie Paik of the Swiss Federal Institute of Technology in Lausanne said, “Everyone has a Swiss army knife somewhere, we want this to be the robot equivalent." She paints a picture of the role of robotics in the home that may differ slightly than what we've been anticipating, "You can keep this in your toolbox, ready to help automate simple tasks around the home."

Paik says that the modules can be combined to achieve a number of tasks, including multimodal locomotion, object manipulation, and stiffness tuning.

Image courtesy of Swiss Federal Institute of Technology.

Lowering the Cost Barrier for Robotics

Fortunately, this modular robot has fast manufacturing times and can be created relatively inexpensively. By combining foam cores and layers of silicone rubber, the bulk of the robot can be created in under two hours.

A vacuum-powered soft pneumatic actuator leverages a vacuum power supply, enabling soft robotic systems with multiple degrees of freedom and diverse functions.

According to the paper's abstract, the vacuum pressure also allows "gripping and stiffening through granular media jamming, as well as direct suction adhesion to smooth surfaces, for manipulation or vertical fixation." This flexible movement pairs with 3-DoF functionality, meaning that the module has three degrees of freedom or three directions in which it can move via single-axis rotational joints.
The use of V-SPAs in this instance is very explicit in its purpose: the team wants to prove that vacuum-powered robots are a viable path forward, even for "larger, more complex multifunctional soft robotic systems." Proving this viability could feasibly be a stride towards accessible robotics all over the world.

Image courtesy of Swiss Federal Institute of Technology.

The Downside That's Also an Upside?

There are certainly drawbacks to soft robotics. These new modular soft robots, like soft robotics in general, lack the power and precision of robots powered by electric motors. These also face a new challenge in that they aren’t as mobile as traditional robotics because they’re attached to a vacuum pump that provides power. This, combined with their foam materials, makes them rather bulky.

Paik, however, thinks that this deviance from traditional robotics may be welcome since many robots make people uneasy. “Binging robots into our lives does not mean that we have to be friends with the terminator,” she says. “It’s about making  things better.”

She believes that her research highlights the effectiveness of V-SPAs in soft robotics and facilitates the consolidation of once disparate subsystems for actuation and specialized tasks, making way for use in larger, more complex soft robotic systems.


Currently, the modular robots are in the prototype stage, which may mean you won’t have one around to, say, change the batteries in your smoke detector for some time. Perhaps, though, these soft robots will inspire designers to take part in this field and accelerate the acceptance of robots in homes—whether by lowering their prices or by making them less Terminator-like.