Ballistic Vests
Technology Roadmap Sections and Deliverables
The selected technology that Team 6 will be spending the remainder of the semester on developing a technology road map is ballistic vest technology (specifically for military and law enforcement applications).
Clear and unique identifier:
- 2BV - Ballistic Vests
This indicates that we are dealing with a “level 2” roadmap at the product level.
Roadmap Overview
The working principle and architecture of Ballistic Vests is depicted in the below.
A ballistic vest works by absorbing the kinetic energy from a high-speed projectile (bullet or shrapnel from an explosion) at the point of impact over a wide area. The ballistic vest is meant to spread the kinetic energy by displacing it across the ballistic vest materials in a process called material deformation. The deformation occurs in two-fold, deformation of the ballistic vest materials as the bullet absorbs the kinetic energy and deformation of the bullet itself, called mushrooming. The remainder of the energy is consumed as heat.
This technology is a lifesaving technology to aid military personnel and law enforcement during their daily activities. A ballistic vest is typically worn on an individual’s chest and is meant to be replaced after it has taken an impact (from high speed projectile or mishandling of vest e.g. dropped) or date of manufacturing has expired. There are six levels of protection (Type I, Type IIA, Type II, Type IIA, Type III, and Type IV). The history of personal armor dates back to 500 BC when chain mail/coat mail was used as a form of individual protection from slashing blows by an edged weapon (e.g. swords). Modern day individual body armor is meant to protect from high speed projectiles. New fibers were discovered in the 1960’s for the possibility to make resistant vests and DuPont developed Kevlar ballistic fabric in the 1970s.
Design Structure Matrix (DSM) Allocation
The 2-BV tree that we can extract from the DSM above shows us that the Ballistic Vest (2BV) is part of a larger initiative on personnel protection (1PP), and that it requires the following key enabling technologies at the subsystem level: 3SA Soft Armor, 3HA Hard Armor.
Roadmap Model using OPM
We provide an Object-Process-Diagram (OPD) of the 2BV roadmap in the figure below. This diagram captures the main object of the roadmap (Ballistic Vest), its various instances including common ballistic vest products, its decomposition into components (front carrier/panel, rear carrier/panel, side carrier/panel, soft armor (front & rear), hard plate (front, back, & sides, etc.), its characterization by Figures of Merit (FOMs) as well as the main processes (Protecting with two states protected and unprotected).
An Object-Process-Language (OPL) description of the roadmap scope is auto-generated and given below. It reflects the same content as the previous figure, but in a formal natural language.
Figures of Merit
The table below show a list of FOMs by which ballistic vest can be assessed.
Alignment with Company Strategic Drivers
The table below shows an example of potential strategic drivers and alignment of the 2BV technology roadmap with it.
Positioning of Company vs. Competition
The figure below shows a summary of other ballistic soft vests from public data.
Technical Model
In order to assess the feasibility of technical (and financial) targets at the level of the 2BV roadmap it is necessary to develop a technical model. The purpose of such a model is to explore the design tradespace and establish what are the active constraints in the system. The first step can be to establish a morphological matrix that shows the main technology selection alternatives that exist at the first level of decomposition, see the figure below.
Financial Model
The figure below contains a sample NPV analysis underlying the 2BV roadmap.
List of R&T Projects and Prototypes
In order to select and prioritize R&D (R&T) projects we recommend using the technical and financial models developed as part of the roadmap to rank-order projects based on an objective set of criteria and analysis.
Key Publications, Presentations and Patents
Ballistic vest comprehensive list of publications, presentations and key patents.
Our technology of choice is the ballistic material used in soft body armor.
The analysis on patent and paper is focused on these two areas, (1) Area 1: what materials can improve soft body armor’s ballistic performance? And getting a material, what structure of the body armor would maximize the material properties?
(2) Area 2: what material properties governs the ballistic performance?
Patent analysis When coming to materials, it is necessary to analyze both material and process. In the soft body armor material history, two patents have been remarkably important.
Patent 1: Hill HW Jr, Kwolek SL, Morgan PW. Polyamides from reaction of aromatic diacid halide dissolved in cyclic nonaromatic oxygenated organic solvent and an aromatic diamine, US3,006,899, DuPont, 1957.
Patent 2: Blades H. Dry jet wet spinning process, US3,767,756, DuPont, 1972. The first patent, US3,006,899 disclosed how to make an aromatic amide polymer which is known later as Kevlar®. Before this patent, the strongest synthetic material is nylon fiber which is polymerized with aliphatic units. DuPont attempted to use aromatic units to replace the aliphatic units in nylon to improve its physical properties such as strength and thermal resistance. They were able to synthesize a wholly aromatic amide polymer as disclosed in this patent filed in 1957 and granted in 1961.
Patent 4: Harpell GA, Paelley I, Kavesh S, Prevorsek DC. Ballistic-resistance composite article, US4,748,064, 1985, Allied Corp.
Patent 5: Harpell GA, Prevorsek DC, Li HL, Flexible multi-layered armor, US5,175,040, 1991. Allied-Signal. When a material breakthrough is achieved, it is hard to make next breakthrough in a short time. Most of the work is to optimized the use of the newly developed material. Soft body armor (ballistic vest) is an article with a structure. Most of the work has been focused on how to optimize the structure of the vest made of the newly developed material. Traditionally the textile soft body armor was made by interweaving. In this Allied Corp (later Honeywell) disclosed a non-woven structure that has improved ballistic performance by aligning fiber unidirectionally. The interweaving was removed from the structure. This structure is claimed in the dependent claim 4:
Claim 4: An article as recited in claim 1 where in said network of fibers comprises a sheet-like fiber array in which said fibers are arranged substantially parallel to one another along a common fiber direction. This kind of configuration is shown in Figure 2-4. This innovation structure improved the ballistic performance as opposed to the traditional interwoven structure. The results are extracted from the patent and compared in Table 2-2.
The improvement is 15.4% by simply changing the structure. This improvement seems not large, but it is indeed significant enough to make difference. Imagine if one soldier wears a vest of 10 lbs weight, and 15.4% reduction in weight is 1.5lbs. If this 1.5lbs are freed and he could carry 1.5lbs more ammunition, that can make a huge difference in time of needs.
Patent 3: Leach J, Fash WG, Ballistic Vest, Burlington Industries, US3,891,996, 1974. Soon after the successful development of Kevlar® fiber (with the patent disclosure in 1974), a ballistic vest patent was filed in 1974 by using aramid (aramid is aromatic amide polymer) fiber. The independent claim (claim 1) in this patent is:
A ballistic vest comprising: at least one member formed of a plurality of layers of alternately placed woven fabric sheets of (1) ballistic nylon fiber and (2) aramid fiber, said member being sewn so as to prevent substantial relative movement between said layers; and means for securing said member to the torso of a person.
Technology Strategy Statement
A technology roadmap should conclude and be summarized by both a written statement that summarizes the technology strategy coming out of the roadmap as well as a graphic that shows the key R&D investments, targets and a vision for this technology (and associated product or service) over time.