[jkelleyrtp]

My biggest recommendation is to get some sort of digital fabrication whether it be a CNC router, mill, 3D printer, or waterjet sponsorship. This absolutely forces students to CAD out the robot because they must have a digital copy in order to produce parts. If you want to play around in the offseason, I recommend getting an X-Carve (upgraded) or a 3D printer. These items have relatively low barriers to entry and can let students quickly turn their parts into actual models.

The X-Carve is slightly harder to get into but is very inspiring after getting it fully tuned and upgraded to your tastes.

As to your question about drawing before build, we come up with concept on a whiteboard and some basic dimensions before CAD starts. However, students eventually find it easier to express their designs through simple 2D sketches using CAD (we use Solidworks). This prevents them from becoming too invested in creating parts and mating things together, and more focused on the geometry and layout of their idea. A fully dimensionsed robot design can take about 20-30 minutes to create and can include all the dimensions and mechanism layout that you need.

IMHO it is very important to get as many people on your mechanical team to learn CAD. Everyone wants to prototype, but few can properly plan out their prototypes without CAD. Even just knowing 2D sketches can greatly benefit your team.