MANUFHAPTICS

Manufacturing of Actuators Integrated in Active Exoskeletons

Background and main goal

In several application areas, such as assistive devices for rehabilitation, soft exoskeletons to support active lifestyles, and haptic devices for teleoperation and for immersive virtual reality gaming, there is a need for compliant active wearables. However, despite rapid progress in additive manufacturing of soft structures, the direct integration of dense arrays of electrically-controlled actuators in printed wearables remains elusive.

The main goal of MANUFHAPTICS is to develop novel functional materials and scalable additive manufacturing processes for soft actuators that are directly integrated in an elastomer exoskeleton. Three types of electrically-driven actuators will be fabricated. The main demonstrator will be a digitally manufactured soft glove, making virtual objects feel real.

Idea and approach

Novel functional materials as well as multi-material printing and hybrid integration processes will be developed to allow the seamless integration of electrically-driven actuators in active soft systems. This will enable a broad range of complex soft active systems, that require no pumps or compressors to achieve complex operation.

The key building blocks of the MANUFHAPTICS project are:

Materials for printable inks: Development of high-performance dielectric materials for high energy density actuators and of inks enabling sacrificial layers which are compatible with different printing tools
Multi-material printing processes: Establishment of digital printing methods, such as inkjet, aerosol jet and direct ink writing, for the deposition of structural and functional materials over multiple size scales
Devices and systems integration: Development of digitally fabricated soft electrostatic actuators and their integration in soft 3D printed structures

With these technologies, three types of actuators will be developed:

High force electrostatic clutch actuators that can block finger joints
Millimeter-sized hydraulically amplified electrostatic actuators for skin stretching
Multi-layer dielectric elastomer actuators for rich tactile feedback.

Demonstrator

Digitally manufactured soft multi-modal haptic glove

MANUFHAPTIC’s main demonstrator will be a digitally manufactured soft multi-modal haptic glove with arrays of actuators and sensors for augmented reality and virtual reality applications. Actuators distributed over the fingers and hand will deliver touch and feedback sensations as well as orientation and blocking of the movement. Additional sensors will provide information on the position of the hand, with technology coming from the SFA-AM project D-SENSE, in which piezoresistive and capacitive soft sensors are produced by direct ink writing.

Technical challenges

Soft actuators with a very high energy-density
Customization of exoskeleton for each user to comfortably exert large forces on different body parts
High-permittivity compliant dielectrics, fluidic coupling, stretchable electrodes, and high breakdown strength polymers designed to be compatible with direct ink writing, aerosol jet or drop on demand manufacturing
Exoskeleton architecture controlled over a range of length scales, i.e., micrometer and millimeter thick layers must be assembled into complex several centimeters long 3D shapes with controlled porosity

Consortium