HARDWARE DESIGN AND PRODUCTION .1 Introduction

The design and production of hardware for command data systems is relatively

unimportant in some situations. In others, it is the essence of the total system design.

Generally, hardware design is the dominant consideration in control systems; whereas software is the quintessence of high level command systems. Since tactical command data systems may be concerned with the control of weapons as well as the command of forces, hardware design is a very important consideration.

Hardware design like software design, is highly dependent upon the system being developed, and there is no such thing as a "typical" system. There are elements of system design, however, that are recurrent, and these are singled out and discussed in some detail. Hardware production may go on concurrently with the hardware design, or it may follow system design and specification. It may consist of a: prototype system or a limited production item. It may include the ultimate production of hundreds or thousands of end items.

Subsequent sections center around the design of a system that results in prototype hardware and touches upon some of the necessary phases in preparing for further production. These phases are not all required for each piece of hardware developed, nor are they an exhaustive list of ali possible design considerations. However, they are representative of the major hardware design considerations required for ACDS.

Section 2.5.2 discusses design considerations, and Section 2.5.3 discusses production considerations.

2.5.2 Phases of the Hardware Design Cycle

This section presents the hardware design cycle in six phases. In the actual design of ACDS hardware, the precise discussions presented here vary with the pieces of equip-ment involved. The six phases of the hardware design cycle are:

1) initiation, 2) Organization, 3) Preliminary design,

4) Principal design, 5) Prototype construction, 6) Test, train, and evaluate.

Each phase is discussed in one of the following sub-sections. Figure 2-7 shows the time spans to be expected for each hardware design phase. Figure 2-8 shows the general information flow of hardware design.

Phase Name Time Involved

1 Initiation 1 day to 1 month

2 Organization 2 weeks to 3 months

3 Preliminary Design 2 months to 2 years 4 Principal Design I year to 10 years 5 Prototype Construction 6 months to 2 years 6 Test, Train, Evaluate 6 months to 2 years

Figure 2-7 Time Spans For Hardware Design Phases

2.5.2.1 Phase 1 - Initiation

Military systems are designed to fulfill an operational requirement as stated by one or more military organizations. Within the U.S. Navy, this is generally a General Operational Requirement (GOR) or a Tentative Specific Operational Requirement (TSOR) issued by the Chief of Naval Operations, or the Commandant of the Marine Corps. This, in time, may result in a Proposed Technical Approach (PTA) supplied by one of the Bureaus, Laboratories, or other technical agencies of the Navy.

A PTA may be generated internally by one of the Navy's "in house" organizations, or may result from a study effort such as ANTACCS. After a PTA has been accepted and approved, a Specific Operational Requirement (SOR) may be issued by CNO or CMC which leads into the preparation of a Technical Development Plan (TDP). Like the

PTA, the TDP may be generated internally by a naval "in house" organization, or outside help may be required. It is at this point that many of the hardware possibil-ities stated in the PTAare firmed up, and the method of system development is pre-sented. A number of decisions are then made such as, the method: of contracting

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(CPFF, Fixed, Price, or CPIF). The result of the TDP may have a great bearing upon the hardware development and it must include reasonable estimates of technical feasibility. '

After the TDP is approved by DDR&E the project can be released for Engineering Development.* Part of this relase is likely to take the form of a set of specifications that is issued to industry to bid on the system either as a whole or in parts. After selection of the successful bidder and award of the contract, the serious hardware design commences. Up to this point, the details have been under the complete

control of the Navy. From here on, most of the details of design are up to the system designer who is more or less free to do as he pleases at the detail level as

long as he stays within the gross constraints of the specifications.

System design is not like a jigsaw puzzle with only one unique solution. It is rather like devising the "best" way to go from Washington to Los Angeles which can have many solutions depending upon the definition of "best" . The fastest route may not be the cheapest, and neither is likely to be the most scenic. Making comparisons of this sort, weighing the advantages, and making the trade-offs and arriving at the

"best" solution to the problem is the essence of engineering. In system design, the overall parameters are often difficult if not impossible to; determine. Before hard-ware can be designed and produced, however, the parameters characterizing the particular piece of equipment must be known and explicitly stated.

The hardware design is thus initiated by a series of rather formal steps which lead to the award of a contract for the development of a system, or for the development of certain pieces of equipment. In either event, the product must be designed according to a rather general specification.

If the specification is for a system, further design and more detailed specification is required before hardware is designed and produced. The steps of a system design

leading to the creation of a detailed hardware specification were discussed in the previous section.

*This process is the subject of Section 2.7 of this volume.

Hardware design and production differ from general system analysis and design in several important respects. A discussion of the organization required for hardware design and production highlights these differences.

2.5.2.2 Phase II-Organization

Though often overlooked, the organization of the "team" is a very important consideration in developing command data system hardware. The organization is important for the reason that it is the nucleus of command and control system for the hardware developer. It es-tablishes the lines of communication between the various key elements, eses-tablishes reporting procedures, and provides for necessary checks and balances. Like a military command and control system, it must provide for positive and effective, yet timely control of all key elements, while remaining flexible and responsive to both external and internal pressures and changes.

During the period when the proposals are being prepared, sales engineering, the general manager and his staff, and others in the organization work together closely, and certain relationships exist that cease when the actual work on the program begins. The effort on the part of marketing decreases significantly, while the participation of the general manager and engineering shows a definite increase. Using the award of a contract as the point of departure, a crucial question presents itself to management: How will we manage this pro-gram? Even though ýhe question may have been brought up and . erhaps even resol-ted -before, the award of the hardware contract requires immediate resolution of this question and implementation of a management plan.

The most common approach is to establish a program office headed up by a person deisgnated as the program manager. Where, in the organization, this program office should be located however, is not so readily determined. Three commonly accepted spots for such program offices are:

1) In a staff capacity advising and acting for the general manager (Box A or B)

2) In a line position on an equivalent level with engineering, manufacturing, etc. (Box C or D)

3) As part of engineering

Regardless of location, the program office is responsible for coordinating the in-house effort, interfacing with the customer and upper management (often representing the customer's viewpoint rather than the company's) and exercising close scrutiny over expenditure of funds.

Smaller, less complex hardware developments tend to be managed under engineering, while larger more sophisticated programs are likely to be managed at a high level where the program manager has direct access to the general manager and may or may not have direct control over elements of engineering, manufacturing and other parts of the organization. Occasionally with m'ajor hardware development programs a separate division of the company will be set up with engineering, manufacturing, and other necessary functions as part of the division.

Before discussing some of the functions of the project office, a few words about quality control seem appropriate. The location of quality control responsibility and personnel seems to vary widely from company to company. The ultimate responsibility for the quality of a product rests with the general manager of the organization. Quite often, however, responsibility for this function is delegated either to engineering or manufacturing. Even though this delegation is a common practice, it is not always the best one. Engineering should be chargod with providing a well-designed and engineered piece of hardware of high quality at minimum cost. Manufacturing is responsible for taking the engineering design and converting it into hardware meeting the engineering specifications at minimum cost. Each of these organizations needs to concern itself with the quality of the end product, but the final stamp of approval should come from outside both organizations.

A preferred approach is to place the responsibility for quality control where it really should be;responsible directly to the generalmanager. This can be either at a staff level or in a line position along with engineering and manufacturing. The latter has many advantages over the staff level organization, but either can provide a very workable solution. The interaction of quality control and other elements of the organization is covered in more detail in the later phases of hardware design and

production.

Another point about the organization should be made before discussing equipment development. An industrial organization must have people to do a good job. The key men of any group undertaking ýan important job should be on hand before the job is started. It is often impossible to hire a crew after contract award. It is poor policy to fire everyone on contract completion. Management people have a great interest in

maintaining a constant or gradually-changing work force. Such work force planning can avoid many training and indoctrination problems, and lessen the effect on general morale imposed by lay-off.

A stable organization is needed to support important programs. The building of such an organization is an important management responsibility.

2.5.2.3 Phase Ill Preliminary Design

The preliminary design phase is based upon, the gen.eral specifications prepared after the completion of the operational analysis and system design. This is discussed in Section 2-4. The general specifications generally cover the gross hardware considera-tions such as environmental and reliability requirements as well as incorporating as many of the details of the preliminary operational description as is necessary.

General constraints affecting all the equipment are incorporated into the specification at this point. A general constraint might, for instance, require that all equipment be so fabricated that it initially can fit through a submarine hatch either as a whole or in pieces.

The technological state-of-the-art, coupled with the cost of implementing a technical approach is the major factor shaping the output of the preliminary design. Specific constraints such as maximum allowable voltage or time limitations on computations to be performed by the equipment also may play an important role here. One important input into the preliminary design phase is the matter of experience and judgment of the people

involved in this phase. Too little experience being brought to bear is likely to result in a less than optimum design, while too much "narrow" or highly specialized experience may result in an overly complex solution to a simple problem or result in a very fine piece of equipment for doing many things that may not really be required.

Although there is no sharply defined point at which Phase Ill ends and Phase IV begins, the preliminary design becomes principal design when:

1) The general internal configuration for the equipment has been completed: and specified.

2) Specific performance specifications have been prepared.

3) Interfaces with external equipments have been specified.

4) A schedule for the principal design effort has been prepared.

5) The proposed design approach has been checked against

require-"ments and specifications to insure adequate compliance.

6) A quality control program has been generated.

At some point in time when most of these items have been covered, the principal

design commences. Parts of the principal design can start before the preliminary design is complete. Interface information, for instance, may be very late in being specified.

Note also that as the preliminary design specificai'ons are going over into the principal design process, they are being checked against the general specification, the opera-tional system description, all interface requirements, and those constraints that may result from the software design effort. This is a continuing effort through the principal design and subsequent phases.

2.5.2.4 Phase IV - Principal Design

The principal design period is generally the longest of any of the phases in most hardware or system developments. It is the period when concepts are finalized and converted into detailed specifications. General specifications from the preliminary design phase are used as the basis for detailed and definitive subunit and component specifications. Unproved techniques are checked out with breadboards; unworkable ones are rejected. At the end of this phase, complete, definitive and workable specifications for the fabrication of prototype hardware are complete and construction can be started,

Breadboarding is an important and useful tool during this phase. Breadboarding is a useful adjunct to, but not a replacement for, simulation. A breadboard of one or of a few distributed logic elements, for example, is sufficient to demonstrate the feasibility of the device and the adequacy of the design, but simulation is necessary to determine how thousands of these would work together and to determine the best ways of tying them together logically. After this determination a breadboard can be used to test the method of interconnection, and modification to the basic design can be made if necessary.

For example, simulation might indicate that the optimum number of mutual inter-connections for each element is ten, while the initial breadboard design might be capable of driving no more than eight without modification. If considered desirable, based upon the simulation results, the breadboard might be modified if this is feasible;

if not, a new simulation might be run using an upper limit of eight interconnections.

Other types of simulaticn also may play an important part during this phase.

Equipment external to the hardware may have to be simulated due to nonavailability of the external equipment or impracticability of its use. Some typical examples are:

1) Simulating radar video for a radar data processor or display.

2) Simulating the output of a computer in the design of a computer-driven display or a computer peripheral device.

3) Simulation of peripheral equipment characteristics in the design of computers.

4) Simulation of RF interference in the design of communication equipment.

5) Simulation of environmental conditions in the development of all types of equipment.

Depending primarily upon the complexity of the hardware, parts of the prototype equipment may go into the construction phase before all the principal design is completed. Equipment component completion should be scheduled in a fashion that ensures completion at about the same time of all necessary subunits that go together to form a unit. Long lead time items, therefore, should start before shorter lead time items. Unfortunately, long lead time items are often the most difficult to design, and a definite effort on the part of the program manager to complete these designs first is

necessary. Care must be exercised to minimize changes that may be necessary to equipment that has been released [o manuf~acturing and result from unknowns in the designs of later specified equipment.

It is during this phase that the key inputs to such management tasks as PERT are

generated. This information concerning the key elements, bottlenecks, milestones and completion times, if not the most important output at this phase, is certainly one of the most useful to the manager and the user who is anxiously awaiting the completion of the program. A rough schedule probably exists at the beginning of this phase which will be refined and polished as the principal design progresses: Scheduling, PERT, critical path analysis, and other related techniques are covered! elsewhere and are not discussed here. Most of these considerations are equally valid for small hardware developments or large and complex system developments, differing only in degree.

Even though the principal design phase may last longer than all other phases combined, it is relatively straightfor,-ward. tt is almost exclusively engineering, in. the t-rue wense of the word, There ir, ca smattering0 o re~eaý'-h in thl.os,: arex uko.c'hi.ng new' and unproved techniques, and also a hint of manufacturing as prototype devices are fabricated, but the principal design phase centers around good old-fashioned engineering.

Toward the end of the principal design phase, interaction with manufacturing and quality control at this point must take the necessary steps to ensure that the engineering design satisfactorily meets the overall quality required of externally and internally generated specifications, and that the manufacture of the equipment does not degrade this design to an unsatisfactory level. The important thing is that a team effort is now necessary even though all members of the team do not appear to be working towards the same goal. The team captain is the program manager, quality control acting as

referee, and close decisions being made -by "top management".

When adequate specifications have been prepared by engineering, manufacturing has accepted them and agreed to fabr;cate the necessary hardware, and quality control is satisfied with the proposed approach and has approved the engineering acceptance test procedure, prototype construction starts.,

2.5.2.5 Phase V - Prototype Construction

Depending upon many factors, prototype construction may be almost exclusively a manufacturing phase or a phase with a great deal of engineering and quality control monitoring. Choosing the fabrication of a small militarized general purpose computer as illustrative if not typical, of such a fabrication process, several of the salie',nt features are discussed subsequently.

Up to this point, much of the design has been a process of breaking the system down into smaller and smaller elements, and defining these in some detail. What may have started as a large and complex tactical command and control system has been divided and subdivided into smaller and smaller bits and pieces until, at this point, specific components such as resistors, capacitors, and transistors must be considered. From this point, the gradual building back into the complete system must start. Much of this

Up to this point, much of the design has been a process of breaking the system down into smaller and smaller elements, and defining these in some detail. What may have started as a large and complex tactical command and control system has been divided and subdivided into smaller and smaller bits and pieces until, at this point, specific components such as resistors, capacitors, and transistors must be considered. From this point, the gradual building back into the complete system must start. Much of this

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