Flyway Hygienic Cover Guide

Common Issues and Relevant Factors

Material Selection and Electromagnetic Effects

The material chosen for the cover should ideally be non-magnetic and non-conductive.

Magnetic materials can distort the magnetic field between the Flyway and the XBots. It will also be attracted to the XBot, causing the cover to lift up and affect the XBot's performance.

Conductive materials like aluminum create high eddy currents, which can slow down the XBots.

316 stainless steel is a good material choice as it is non-magnetic and offers excellent hygienic properties. Be sure the steel is not work-hardened, as this increases magnetism.

Thermal Expansion and Bulging of the Cover

There will be uneven heat generation on the surface of the Flyways due to the actuation of the XBots. The hotter areas of the cover will suffer from thermal expansion and make the cover bulge. This issue is more common in large, uncooled systems. For example, a 40°C temperature rise could result in a 0.6mm linear expansion of the cover per meter of Flyway.

Cover Thickness

A thicker cover requires the XBots to levitate higher, reducing system efficiency and available actuation force.

Thicker covers are easier to source and maintain flatness and easier to weld. But if thermal expansion causes it to bulge, it will do so with more force. Additionally if the cover naturally has even a small curved shape it will require a much greater force to be held flat against the Flyway top surface

Potential Solutions

Liquid Cooling

Liquid cooling is very effective to address thermal expansion, and it can often resolve bulging issues on its own. To implement this, run a chiller in series through the cooling ports on the Flyways and set it close to room temperature.

Double Sided Tape

The easiest solution to implement, and it can be effective for smaller systems with less intensive use, where the primary issue isn't bulging but rather keeping the cover from moving or being lifted by the XBots. The downside is that it adds to the overall cover thickness.

Low Melting Point Polymer (Wax)

Apply a low-melting-point polymer or wax to the Flyways and then place the cover on top. Activate force mode in the negative Z-direction (downwards) with the XBots. This will generate heat to melt the wax while simultaneously pushing down the sheet. Then, activate water cooling to solidify the wax. If the cover needs to be removed, simply turn off the water cooling and use the XBots to heat the system.

Pressure Difference

This solution requires the cover to be fully sealed and an external piece of equipment to create a pressure difference. A difference of a few PSI is enough to ensure the cover remains stuck to the Flyways. We have created this solution by running a vacuum pump inside the Flyway enclosure.

Tension

Mechanical tension across the cover sheet can help prevent bulging.

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Stiffening ribs

Adding stiffening members between each flyway to anchor the cover sheet at more points will help prevent significant bulging. However, this will create gaps between the Flyways.

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Bond the cover

Apply a removable protection tape to the Flyway surface (eg. Hard Surface Protection Tape - 24" x 200' S-12213 - Uline) and bond the stainless steel sheet to the protection tape. The stainless sheet will be damaged during removal, but the Flyways will be protected by the tape.