CU Boulder Team Builds Shape-shifting Display With Actuator Technology

August 09, 2023 by Aaron Carman

The 3D display table can dynamically respond to touch, sort items, and create pop-up displays—and it can perform multiple functions at once.

Researchers from Colorado University Boulder (CU Boulder) have developed a morphable 3D display that can change its shape to add a new dimension to robotics. The actuated display builds off previous CU Boulder research into artificial muscles for robotics and represents the first step toward giving users a new way of interacting with computers.


A CU Boulder team has developed a 3D display

A CU Boulder team has developed a 3D display capable of displaying scrolling text, interacting with real-world objects, and responding to external stimuli at the same time. Image used courtesy of CU Boulder Today

While the display is still a working prototype, the CU Boulder team has reported results showing the potential for the technology to revolutionize the robotics industry. This article gives an overview of the team’s research into soft robotics and the role that electronics play in adding new human-computer interactions.


Muscle-motivated Robotics

At the core of the 3D display are numerous Hydraulically Amplified Self-Healing Electrostatic (HASEL) actuators that create motion in a 3D table. These actuators, also developed in conjunction with CU Boulder, aim to replicate the dynamics of human muscles by extending and contracting while also being flexible (and biodegradable, as a plus).

Driving a single actuator is in and of itself a challenge since each actuator must be independently driven between 0 and 8 kV to produce 12 mm of deformation. As such, developing a 10 x 10 array of actuators required careful design to ensure the device was both functional and safe.


HV distribution network within a small area

The system block diagram shown in (e) highlights the need for a complex HV distribution network within a small area. Image used courtesy of Nature Communications

In addition to the driving electronics, the 10 x 10 display also includes a feedback loop to precisely position each element. This feedback loop is formed by a high-voltage sensor at the input of the actuator and a magnetometer built into each pixel. The magnetometer translates a change in deformation to a change in output, thanks to the magnetic block on each actuator.


Electronic Lifelike Motion

The researchers developed the actuators to mimic the dynamics of biological muscular tissue using gel electrodes and a soft, biodegradable interior. In a larger sense, however, the 10 x 10 HASEL actuator array may enable new applications for future digital interactions.

Because the HASEL actuator table can physically manipulate real-world objects, the 3D display brings a sense of touch to the digital world and make long-distance human interaction more similar to real-world interactions. 


The HASEL actuator technology

The HASEL actuator technology uses a combination of gel electrodes and a biodegradable transformer fluid to create an actuator that responds similarly to human muscle tissue, paving the way for more human-like robotics. Image used courtesy of Science Advances

So far, the researchers have proven the HASEL array table's ability to sort balls based on color and respond to human touch with real-time feedback. In addition, the HASEL array table can generate readable scrolling text, demonstrating the precision of the actuators.


New Robotic Senses

While 3D robotic interaction can certainly impact communications and social interaction, it may also prove useful in industrial settings where human-like robotic hands could manipulate controls in a dangerous environment or “hand-sort” products remotely.

First, however, researchers must find a way to scale down the HASEL actuators. Higher resolution can enable more complex operations (although with a proportionally more complex control algorithm) and make the 3D display more practical.

The CU Boulder team’s current contribution (literally) adds a new dimension to the ever-expanding robotics field that could shift the way humans interact with their digital counterparts.