Issue link: https://www.e-digitaleditions.com/i/1255991
July/August/September 2020 I 23 PROPOSAL SCOPE OF WORK & SPECIFICATION IT COORDINATION GUI DEVELOPMENT INSTALLATION COMMISSIONING CONFIGURATION/ PROGRAMMING SIGN OFF FIGURE 7: The AV project lifecycle from a control system design perspective. How should designers and installers approach designing and building an AV control system that meets the client's needs and provides a user experience that everyday users will embrace? Here is a time-tested roadmap (Figure 7). Control hardware provides physical links between the human users and the devices that accept, process, and display the multimedia AV content. Control software lives inside the control hardware, providing the smarts to implement the user interface and to translate user requests into machine commands. DESIGNING, INSTALLING, AND COMMISSIONING AV CONTROL SYSTEMS Proposal—Determine Requirements and Options for Meeting Them All designs begin with tradeoffs between competing priori- ties, namely budget, design features, aesthetics, and reli- ability. Budget is usually the overriding factor with one notable exception: critical operations such as emergency dispatch centers where reliability takes priority. The goal is to meet clients' needs at a price they can afford with a design that provides maximum functionality with ease- of-use, intuitive user interface, and solid reliability. If the wish list outstrips the budget, know what the must-have features are and be prepared to provide options for scal- ing back features to reach a viable cost without crippling the system. When approaching a control system design, iterate the following four-step process to arrive at a realis- tic set of requirements: Step 1: Determine what each device must do. Step 2: List which control and status functions as well as control ports are available for each device. Decide what kind of infrastructure is needed by reviewing construction drawings and/or performing a site sur- vey to determine device locations, cabling, network drops, network security requirements, and provisions for future expansion. Step 3: Analyze which control method is simplest and most reliable. Step 4: Determine that the chosen solution can be implemented within the available budget. As an admittedly oversimplified example of how to follow this process, consider a VTC codec. The codec can be controlled via an IR remote, RS-232 control port or an Ethernet connection. Assume that each control method is equally accessible to install. If the user only desires to emulate the functions available with the IR remote, the choice is simple. Stay with IR. However, what if the user also wants to see an incom- ing call notification appear on a touchpanel? IR cannot provide this capability; RS-232 or Ethernet would be the preferred choices. If the IT department rejects mixing AV control with the existing enterprise network or a separate AV control Ethernet network does not already exist, there is just one cost-effective choice: RS-232.