Business case: Bule Hills Water Authority

Sample Solution

Blue Hills Water DMS Embedded System Block Diagram (By Bard)

                  +--------------+
                  |   Sensors    |
                  +--------------+
                          |
                  +--------------+
                  | Analog-to-Digital Converter (ADC) |
                  +--------------+
                          |
                          V
                  +--------------+
                  |   Processor   |
                  +--------------+
                          |
                  +--------------+
                  |   Memory     |
                  +--------------+
                          |
                  +--------------+
                  | Actuators     |
                  +--------------+
                          |
                  +--------------+
                  |  Human Interface | (Display, Controls)
                  +--------------+

Question 2: Embedded OS Selection

Option 1: Adapt an Existing OS

Advantages:

• Faster Development Time: Existing OSes have a proven codebase and development tools readily available, accelerating development.
• Reduced Development Cost: Existing OSes are often open-source or commercially licensed with established pricing, making them potentially more cost-effective.
• Community Support: Existing OSes often have a large user base and active community for troubleshooting and assistance.

Disadvantages:

• Bloatware: Existing OSes may have features or functionalities not needed for the specific application, increasing resource usage and complexity.
• Limited Customization: Adapting an existing OS may not allow for complete control over its behavior, potentially hindering optimal performance for the DMS.
• Security Vulnerabilities: Existing OSes might have known vulnerabilities if not actively maintained, posing security risks.

Full Answer Section

Option 2: Design a Customized OS

Advantages:

• Optimized Performance: A custom OS can be tailored specifically for the Blue Hills DMS hardware and functionalities, leading to optimal resource utilization and real-time performance.
• Enhanced Security: A custom OS allows complete control over security features, potentially mitigating vulnerabilities present in existing OSes.
• Reduced Footprint: A custom OS can exclude unnecessary functionalities, resulting in a smaller memory footprint and potentially lower power consumption.

Disadvantages:

• Increased Development Time and Cost: Designing a custom OS is a complex task requiring significant development expertise, leading to potentially higher costs and longer development times.
• Limited Support: A custom OS lacks the established community support available for existing OSes, making troubleshooting and future modifications more challenging.

Recommendation:

For the Blue Hills DMS, adapting an existing Real-Time Operating System (RTOS) like FreeRTOS or uC/OS-II could be a good compromise. RTOSes are designed for embedded systems, offer fast response times, and have a smaller footprint compared to general-purpose operating systems. While some customization might be needed, the development time and cost would likely be lower than a fully custom solution.

Question 3: Smart Water Meter Embedded OS

Purpose-Built Embedded OS for Smart Water Meters:

Recommendation:

For smart water meters with limited resources, I recommend using a lightweight Real-Time Operating System (RTOS) specifically designed for Internet of Things (IoT) applications. Some popular options include:

• Contiki: An open-source, highly portable RTOS ideal for memory-constrained devices with networking capabilities.
• Zephyr: Another open-source RTOS with low power consumption and support for various communication protocols.
• RIOT: A flexible RTOS designed for resource-constrained devices with modular architecture for customization.

Advantages of these options:

• Low Resource Footprint: They operate with minimal memory and processing power, allowing efficient operation on battery-powered smart meters.
• Hardware Adaptability: They are often designed for a wide range of hardware platforms with easy porting capabilities.
• Support for Applications and Protocols: These OSes typically support networking protocols like LoRaWAN or cellular, enabling communication with the central system.
• Robustness: They are designed for reliable operation in harsh environments.

Question 4: Blue Hills Water DMS - Multi-OS on Single Hardware

Solution:

Blue Hills Water Authority can achieve running multiple operating systems on a single physical hardware using Virtualization.

Virtualization allows partitioning a single physical server into multiple virtual machines (VMs). Each VM can run its own dedicated operating system and applications, essentially creating multiple isolated computing environments on the same hardware.

Advantages:

• Reduced Hardware Costs: Virtualization allows consolidating multiple physical servers onto a single machine, saving on hardware acquisition and maintenance expenses.
• Increased Server Utilization: Virtualization enables better utilization of server resources by running multiple workloads simultaneously.
• Improved Resource Management: Virtualization tools offer centralized management and resource allocation for VMs, optimizing resource usage.
• Simplified Management: Blue Hills can manage all their OSes and applications from a single platform, simplifying IT operations.

Popular Virtualization Solutions:

• VMware ESXi