Properties of athletic mouth protectors and materials.
The properties of a variety of mouth protectors and sheet materials used to fabricate custom mouth protectors were determined in order to recommend limits for a specification. Hardness, water sorption, water solubility, impact absorption, and tear strength were measured, and limits for these properties were suggested.
Mouth Protectors in Junior Football Players.
In brief This study tested Sta-Guard and Proform mouth protectors that were worn by 280 football players aged 9 to 12 years. Laboratory studies were also conducted to test tensile and tear strength, dynamic modulus and resilience, and hardness. The players received new mouth guards every two weeks for 12 weeks and reported any problems with gagging, taste, speech, feel, and durability. Ninety percent of the boys preferred the Sta-Guard mouth protector, stating that it was softer, more resilient, and more comfortable than the Proform mouth guard.
Economics of General-Purpose Assembly Robots
Summary A study of the comparative economics of various automatic assembly systems using general-purpose assembly robots is described. In the study, use is made of a “typical” candidate assembly whose profile is obtained from statistical analysis of actual products submitted by interested companies. It is shown that the choice of assembly system and the various parts presentation methods depends on three main factors, namely: the annual production volume per shift, the number of parts in the product and the equipment payback period.