FIRST LEGO League is all about learning as reflected in the Core Value “what we learn is more important than what we win”.
In this spirit, I’ve gone ahead and ordered another LEGO Education Pneumatic kit (add-on kit #9641) in addition to the one I purchased early in our season. Although our rookie season was a bit of a blur, my hope is that this year we can master pneumatics and incorporate one or two pneumatic-powered solutions into our robot challenge this fall.
Pneumatics is the “study and application of pressurized gas to produce mechanical motion.” Most people usually don’t directly encounter pneumatic-powered systems outside a dentist drill or message delivery tubes at banks. Yet in Europe it is known as the fourth utility (after electricity, gas and water) with 10% of all industrial energy (80 terawatts) used to produce compressed air.
LEGO V8 Pneumatic Powered Engine
(probably not the most efficient design for a pneumatic engine)
While rapid innovation in electronics and control systems appear to be gaining market share, pneumatics powered devices offer some unique benefits: (1) Simplicity (standard tanks and on/off control), (2) Reliability (better shock resistance and independent of power grid) and (3) Safety (low/no chance of spark, fire or explosion such as in mining). In fact, some companies are looking to create environmentally more friendly automobiles powered by compressed air.
Peugeot Citroen show off their hybrid air vehicle
This fall we considered using the pneumatic tank to launch the soccer ball into the net. As it turned out, over the course of our tournaments we saw a few, usually advanced, teams use pneumatics. Far more teams seemed to use a simple rubber band powered mechanism for the Soccer Mission (FlopBotZilla) or a dedicated armature motor (FlopBot). The rubber band mechanism was a more elegant solution in terms of costs/parts and leaving more flexibility for use of the motorized armature, but reliability depended greatly upon mechanism design.
However, here is an elegant solution using pneumatics to solve a FLL mission from 2008. Climate Connections Missions completed: bike, laptop, insulation, open windows, turn off lights, raise house:
Pneumatics is simply one of the many potential power sources we discussed this season (electric/motor, mass in a gravitation field, deformation/compression of rubber bands/springs). However, they have they introduce an interesting set of physics principles we can touch upon (Ideal Gas Law, Thermodynamics). Let’s hope this fall we’ll see a mission that lends itself to a natural solution via pneumatics.