Pills come in various sizes and shapes, and because of that, the cartridge template needs to be modular enough to accommodate different designs. We'd also like it to be flexible enough to accommodate ideas and designs we haven't though of yet. I'd ideally like the size and shape of the cartridge to be completely flexible (as long as it fits into the proper envelope). The only rigid part of the design would then be the mounting, actuation, and machine readable portions of the cartridge.