In response to an increase in the number of new buildings under construction at Stanford we were commissioned to build a prototype TaRgeted Extremely Ballistic Universal Containerized Heavy Engineering Truck (TREBUCHET) within three weeks. The ultimate goal of such a useful technology was to deliver construction materials autonomously by moving to a particular staging area and launching them in some manner to a construction site. Our prototype (code name: the underwater ninja burrito) needed to fit within a 1' by 1' by 1' cube, cost less than $200, and communicate with an external device (code name: LOC).
Through communication with the LOC, the under water ninja burrito ascertains when the construction cycle, lasting a total of 2 min and 18 sec, begins. The LOC then specifies which of three staging areas to reach, and the under water ninja burrito proves it is positioned at the staging area by reporting the current magnetic frequency emitted from it. Upon 2 successive correct reports, the LOC commands which construction site has been opened and the under water ninja burrito delivers the construction materials in a targeted, extremely ballistic way. Once the underwater ninja burrito is out of ammo, it can refill (5 at a time) at the supply depot. During the last 18 seconds of the cycle things get really wild: all construction sites are open and the goal is to shoot as many foam balls into any of the paint buckets.
Further details on the project are explained in the following document.