B9 Robot Collar Section

B9 robot collar construction reference. See the full B9 robot construction overview.

Frequently Asked Questions

What is the B9 robot collar and why is it distinctive? The B9 robot collar is the accordion-style flexible section connecting the torso to the head assembly. Its pleated, bellows-like appearance allows the head to rotate and tilt while maintaining visual continuity between body sections. It is visible in almost every on-screen shot of the robot and its proportions — too short or too long — immediately affect the correctness of the overall silhouette.

What inner diameter must the B9 collar have? The collar’s inner diameter must fit over whatever neck and head support structure is being built — typically a 3–4 inch diameter aluminum tube that serves as both the structural rotation bearing surface and the wire chase for head-mounted electronics wiring. The outer diameter determines the visual proportion relative to the torso and must match reference images from the target season.

What is the most accurate collar material and how is it built? Cast silicone or flexible urethane rubber (Shore A 20–30) from a mold of a sculpted master is described as the most accurate collar construction, reproducing the correct surface texture in a one-piece flexible collar that eliminates assembly seams. The disadvantage is the investment required in mold making for a collar-sized piece, which requires significant silicone volume.

How are seams managed in foam or vacuum-formed collar construction? Construction seams in foam or vacuum-formed collar sections should be positioned at the back of the robot where they are less visible to viewers, or hidden within the pleat geometry itself. The collar must be fitted incrementally — testing against both the torso top edge and the rotating head geometry rather than finishing it completely before checking fit against both sections.