Collaboration & Innovation

A collaborative partnership leveraging Cubbison’s single-source capabilities results in ESTAT’s simplified, cost-reduced, electrostatic clutch assembly. 

Company

ESTAT Actuation designs, engineers and manufacturers electrostatic clutches, brakes, locks and latches for robotics applications. Electrostatic clutches work by using electrostatic adhesion to create friction between two surfaces, typically two flexible, metallized electrodes separated by an insulating material. When a voltage is applied, the electrostatic attraction between the charged surfaces pulls them together, increasing the normal force and the frictional force between them, thus engaging the clutch to transfer torque. When the voltage is turned off, the attraction disappears, and the surfaces can slide freely again. These products are 10x lighter, 10x more compact and 1,000x more efficient than traditional brakes, which enables robotics developers to dramatically reduce the weight of their systems and extend battery life.

Situation

ESTAT was developing a complex electrostatic clutch module consisting of six components. These modules are the building blocks of ESTAT’s clutches and brakes. They stack to create brakes with more holding torque. The design presented design-for-manufacturing difficulties, especially regarding assembly. The specialized materials used by ESTAT also demanded precise handling. The components required specific thickness requirements, and needed to fit within a constrained space.

ESTAT partnered with Cubbison as their manufacturing partner because Cubbison is one of the few manufacturers that offers all these necessary processes—screen printing, laser cutting and assembly—under one roof. Online or overseas suppliers are inflexible and unable to meet stringent requirements or adjust processes to meet unique needs.

Solution

Cubbison provided critical feedback regarding the difficulty of assembling the clutch modules based on the original specifications. An iterative and collaborative design process then worked through the intricacies of manufacturing and redesign. Cubbison supplied screen printing, laser cutting and assembly services to make the flex circuit portions of ESTAT’s clutches as well as build the modules themselves. While ESTAT supplies some components, Cubbison has worked to increase the number of items and services we offer.

Cubbison used an innovative screen-printing process that laid down the material that acts as the “glue” when current is applied to the clutch. This required the use of a functional ink—not just a color. Cubbison worked with ESTAT to provide several prototype versions of the clutches before settling on a final design. These prototype versions involved varying print thicknesses, and conductive materials. Achieving the required layer thickness demanded precise operational changes, including adjusting the viscosity of the inks, controlling the speed of the squeegee during printing, and determining specialized cure times using the ovens.

Results

Product Simplification

Through collaborative iteration and redesign, ESTAT reduced the number of components required for the electrostatic clutch to operate. The redesigned product accomplished the same goal with significantly fewer components.

The products developed by ESTAT and manufactured by Cubbison were recently displayed at the Japan Mobility Show as part of Suzuki’s new MOQBA prototype II system.

Cost Reduction

This simplification resulted in a product that was less expensive to manufacture, as the original design would have necessitated substantial manual labor.

Improved Efficiency and Lead Times

The design changes made the product easier for Cubbison to manufacture. This improved manufacturability allowed Cubbison to provide ESTAT with larger product volumes, lower costs, and shorter lead times.

The ability to offer all the necessary processes (screen printing, laser cutting and assembly) under one roof provided a unique advantage to ESTAT that most other manufacturers cannot match.