flexDrive

Cut 16 (or fewer) segments of 33ga polyimide tubes to around 6 cm length. This size of polyimide tube results in average electrode pitches of ~250 micron, though electrodes are free to move within its guide tube.

Glue the guide tubes into rows with superglue and arrange rows to form linear arrays

Make sure that no glue gets into the tubes, and that the tubes are free from glue above a consistent depth so they are free to fan out at that depth.

For guide tubes that are not supported by a layer of tubes from below add shorter lengths of tubing to prop them up.

To add a fiber to the array later, coat a piece of fiber or a steel cannula of the same diameter with mineral oil, and arrange into array like a guide tube. This will function as a place holder. Make sure that the type and amount of oil works for ensuring that the cannula can later be removed - test this first to avoid destroying a guide tube array.

Alternative: If permitted by the spatial layout of the guide tube array, an additional polyimide tube can be used to house optical fibers instead of using a place holder that is removed after gluing. For 125micron fibers, an additional 33ga tube works well, for other diameters larger tubing has to be used.

After the polyimide tubes are arranged into the desired pattern, fix them with a thin layer of epoxy.

After the epoxy has cured, carefully remove the placeholder for the fiber.

Cut 16(or fewer) segments of 33ga polyimide tubes to around 6 cm length

Cut a piece of large diameter polyimide tubing (we use 22ga) or steel cannula to the desired length (We use ~6mm for relatively medial cortical implants where the drive can be placed close to the skull - requirements will vary depending on the protocol). If using steel, make sure that there are no sharp edges left on the cannula after cutting.

Bundle the tubes into the larger polyimide tube or steel cannula by adding more tubes one at a time and gently rearranging them.

To add a fiber to the array later, coat a piece of fiber or a steel cannula of the same diameter with mineral oil, and arrange into array like a guide tube. This will function as a place holder. Make sure that the type and amount of oil works for ensuring that the cannula can later be removed - test this first to avoid destroying a guide tube array.

Alternative: If permitted by the spatial layout of the guide tube array, an additional polyimide tube can be used to house optical fibers instead of using a place holder that is removed after gluing. For 125micron fibers, an additional 33ga tube works well, for other diameters larger tubing has to be used.

Glue the guide tubes to each other and to the cannula using superglue. Make sure no glue is sucked up to the upper end of the cannulae by capilary action, otherwise the guide tubes won't be able to fan out in the drive body.

Stabilize the polyimide tubes with a thin layer of epoxy so they stay in place when cut later.

After the epoxy has cured, carefully remove the placeholder for the fiber.