For a while now we've been planning to launch on Kickstarter with two versions of FarmBot Genesis: a "standard" sized device measuring 1.5m wide, 3m long, and 0.75m tall; and an "XL" device measuring 3m wide, 6m long, and 1m tall. In fact, the most recent version of the hardware prototypes (V0.9) have been designed with larger plates and extrusions, and more V-wheels to help strengthen and stiffen the tracks, gantry, cross-slide, and z-axis for the larger sized form factor. The design intention is that one set of hardware components could be used to build either sized device, or any size in between - a scalable FarmBot. The only modifications would be the need for longer cabling, tubing, and belts; and extra extrusions and plates for the larger capacity.
However, even with the latest prototypes, we have decided that we would rather launch with just one sized device - the "standard" sized FarmBot Genesis. Here are our reasons:
Simplicity - With two devices comes two kits, two sets of packaging, more components to order and have on stock (longer wiring harnesses, etc), two sets of assembly instructions, marketing two slightly different value propositions, and providing customer support for two devices. We're a small team with limited resources. Adding a second version of our flagship device to our launch campaign and business operations will undoubtedly be more complex and difficult than launching with one device. We'd rather start small and "do it right", than try to "do it all" and fail to do anything well.
Speed - A more simple product launch of just one device will allow us to launch sooner and ship devices faster. It is easy to fall into a trap of continuously adding features and making changes in lieu of shipping what you already have developed. Launching sooner will allow us to gain feedback quicker, build the FarmBot community and expand our team faster, and iterate more rapidly.
Engineering Reliability - While we think the design intention for a scalable device is good, it is only feasible to a certain extent. Right now, the FarmBot Genesis hardware scaled to the XL size does not appear to be reliable - there is still too much flex within the system, and other challenges begin to arise (such as thermal expansion) when the hardware is pushed to these scale limits. In order to solve these scale challenges, there need to be more serious modifications made to the design likely including a switch to larger motors, an A-frame style Gantry structure, and a different material choice for the tracks. Such modifications however would then make the smaller devices significantly overbuilt, pricier, and less functional. Ultimately, we think that a FarmBot the size of Genesis XL will need to be a completely separate design that lives up to its name, rather than trying to squeeze too much scale out of the slimmer standard design.