Section I
TESTING, DATA COLLECTION, AND ANALYSIS
IX.1 Fit and Function Test
The Fit and Function test determined how much more or less the prototype hindered mobility when compared to a control vest. During use in high risk situations, it is imperative than an officer not be hindered by the body armor he or she is wearing. Because the team did not have objective measurements for what would qualify as “not hindering movement”, we decided to do a comparison between the prototype and a vest that an SRO would have to be comfortable with using. The test also served to show that the prototype was properly tailored to it the SRO before the team proceeded with the Usage test, where the SRO would be wearing the vest for extended periods of time.
The test showed that the vest performed better in almost all aspects over the control test. The few areas it feel through were in ease of putting on and taking off, and slight hindrance in reaching for the handcuffs.
The team decided to consolidate the velcro into fewer straps so that the vest would be easier to put on and take off without the assistance of anyone else. The team also decided that putting elastic on the inside of the vest would keep the vest from hanging over the handcuffs.
The Fit and Function test determined how much more or less the prototype hindered mobility when compared to a control vest. During use in high risk situations, it is imperative than an officer not be hindered by the body armor he or she is wearing. Because the team did not have objective measurements for what would qualify as “not hindering movement”, we decided to do a comparison between the prototype and a vest that an SRO would have to be comfortable with using. The test also served to show that the prototype was properly tailored to it the SRO before the team proceeded with the Usage test, where the SRO would be wearing the vest for extended periods of time.
The test showed that the vest performed better in almost all aspects over the control test. The few areas it feel through were in ease of putting on and taking off, and slight hindrance in reaching for the handcuffs.
The team decided to consolidate the velcro into fewer straps so that the vest would be easier to put on and take off without the assistance of anyone else. The team also decided that putting elastic on the inside of the vest would keep the vest from hanging over the handcuffs.
IX.2 Usage Test
The Usage Test was used to determine if the prototype would perform better or worse in terms of comfort compared to a control vest. For everyday vest use, comfort is top priority. Because the team did not have objective measurements for what would qualify as “comfortable”, we decided to do a comparison between the prototype and a vest that an SRO would have experience using.
The results of the Usage Test were very positive - in almost all aspects the designed vest performed better than the control vest in terms of comfort. The only negatives the vest had were that it was difficult to tell which straps went to which velcro patch, and that there were so many straps. To account for these concerns, the team combined several of the straps so that there were only two side straps.
The Usage Test was used to determine if the prototype would perform better or worse in terms of comfort compared to a control vest. For everyday vest use, comfort is top priority. Because the team did not have objective measurements for what would qualify as “comfortable”, we decided to do a comparison between the prototype and a vest that an SRO would have experience using.
The results of the Usage Test were very positive - in almost all aspects the designed vest performed better than the control vest in terms of comfort. The only negatives the vest had were that it was difficult to tell which straps went to which velcro patch, and that there were so many straps. To account for these concerns, the team combined several of the straps so that there were only two side straps.
IX.3 Ballistic Resistance Test
The Ballistic Resistance Test determined if the Kevlar panels directly treated with shear-thickening fluid were any more effective than the control panels, which were untreated.
The results of the test were less than promising; the control panels performed better than the treated panels. While none of the bullets penetrated either set of panels, the treated panels had larger backface deformation when compared to the untreated panels.
After further research, the team discovered that the most likely reason that the treated panels performed worse than the control panels was that soaking the Kevlar fibers in fluid weakened the bonds between them, causing the panels as a whole to be weaker. This could have been from oversaturation of PEG, the incomplete evaporation of ethanol, or some other factor. Our conclusion was that The team could have placed the shear-thickening fluid in its own container, simply placed alongside the Kevlar panels.
IX.4 Coverage Test
The coverage test determined if the prototype vest covered more area than the standard assault (control) vest. Oftentimes, most officer deaths while wearing armor are caused from them getting shot in places that the vests don’t usually cover (lower abdomen, sides, etc.). The area covered was determined by calculating the surface areas of the prototype and control vests and comparing them.
The control vest had a front surface area of 298 in^2 (.19 meters squared), and a back surface area of 250 in^2 (.16 meters squared). The prototype vest had a front surface area of 472 in^2 (.3 meters squared) and a back face surface area of 436 in^2 (.28 meters squared). It should be noted that the extra coverage comes at the sacrifice of no extra weight or reduced flexibility.
IX.5 Weight Test
The Weight Test was used to determine if the vest fulfilled the condition of being less than 8 pounds. The team first weighed a container for the vest, then zeroed the scale and placed the vest inside, since the weight shown then should be the weight of the vest itself.
The prototype vest with panels weighed 7 lbs, 2 oz (3.23 kg). Without panels inside, the carrier weighed 1 lb, 12 oz (.79 kg). The test was a success because the vest weighed similarly to a standard issue vest while covering much more area.
The Ballistic Resistance Test determined if the Kevlar panels directly treated with shear-thickening fluid were any more effective than the control panels, which were untreated.
The results of the test were less than promising; the control panels performed better than the treated panels. While none of the bullets penetrated either set of panels, the treated panels had larger backface deformation when compared to the untreated panels.
After further research, the team discovered that the most likely reason that the treated panels performed worse than the control panels was that soaking the Kevlar fibers in fluid weakened the bonds between them, causing the panels as a whole to be weaker. This could have been from oversaturation of PEG, the incomplete evaporation of ethanol, or some other factor. Our conclusion was that The team could have placed the shear-thickening fluid in its own container, simply placed alongside the Kevlar panels.
IX.4 Coverage Test
The coverage test determined if the prototype vest covered more area than the standard assault (control) vest. Oftentimes, most officer deaths while wearing armor are caused from them getting shot in places that the vests don’t usually cover (lower abdomen, sides, etc.). The area covered was determined by calculating the surface areas of the prototype and control vests and comparing them.
The control vest had a front surface area of 298 in^2 (.19 meters squared), and a back surface area of 250 in^2 (.16 meters squared). The prototype vest had a front surface area of 472 in^2 (.3 meters squared) and a back face surface area of 436 in^2 (.28 meters squared). It should be noted that the extra coverage comes at the sacrifice of no extra weight or reduced flexibility.
IX.5 Weight Test
The Weight Test was used to determine if the vest fulfilled the condition of being less than 8 pounds. The team first weighed a container for the vest, then zeroed the scale and placed the vest inside, since the weight shown then should be the weight of the vest itself.
The prototype vest with panels weighed 7 lbs, 2 oz (3.23 kg). Without panels inside, the carrier weighed 1 lb, 12 oz (.79 kg). The test was a success because the vest weighed similarly to a standard issue vest while covering much more area.