Advanced Communication Controller for Defense Project

Introduction

A niche defense equipment and subsystems manufacturer faced a complex challenge in one of their critical projects: upgrading a ship's radar system. The project required seamless integration of multiple communication protocols and precise platform stabilization. Recognizing the need for specialized expertise, the company approached Softwise Mechatronics to develop an embedded solution that could bridge these diverse protocols within stringent time constraints.

Identifying the Challenges

Through comprehensive discussions with the client's engineering team and a thorough analysis of the project requirements, we identified several key challenges:

1. Protocol Diversity: The main computer used a proprietary protocol based on RS485 with non-standard baud rates, while other components used different protocols: 
    
   • Motor drives: EtherCAT protocol
   • Encoders: EnDat 2.0 protocol
2. Real-time Communication: The system required real time message conversion between these protocols to ensure optimal radar performance within microsecond level delays.
3. Platform Stabilization: The radar needed to be installed on a stabilized platform, requiring precise control and feedback mechanisms.
4. Environment: The solution needed to be robust enough to withstand the harsh conditions of a naval environment.
5. Time and Budget Constraints: The project had strict deadlines and budget limitations.

Our Solution

Based on our analysis and expertise, we developed a comprehensive solution:

1. Hardware Selection: We chose one of the TI's Sitara microprocessor for its powerful processing capabilities, flexibility, and support for multiple communication interfaces.
2. Software Development:  
   • Implemented the EtherCAT stack for motor control communication.
   • Integrated EnDat 2.0 protocol libraries for precise encoder readings.
   • Developed custom firmware to handle the proprietary RS485-based protocol.
3. Protocol Conversion: We designed an efficient message routing and conversion system to seamlessly translate between the different protocols in real-time.
4. Platform Stabilization: Implemented a sophisticated feedback control system using the encoder data to maintain platform stability in various sea conditions.
5. Optimization: Fine-tuned the system to meet the strict timing requirements, ensuring all protocol conversions occurred within the specified limits.

Technical Deep Dive

Communication Protocols

1. RS485 (Proprietary): 
    
   • A robust, differential signaling standard capable of long-distance communication.
   • We implemented a custom driver to handle the non-standard baud rates required by the main computer. 
2. EtherCAT: 
    
   • A high-speed Ethernet-based fieldbus system developed by Beckhoff Automation. 
   • Offers precise synchronization and deterministic communication, crucial for coordinated motor control. 
   • We utilized the EtherCAT stack to manage real-time communication with the platform motors.
3. EnDat 2.0:  
   • A digital, bidirectional interface developed by HEIDENHAIN specifically for position encoders. 
   • Provides high-resolution position data with built-in diagnostics. 
   • We integrated EnDat 2.0 libraries to accurately read encoder positions for platform stabilization.

Platform Stabilization Feedback Control

To ensure precise radar positioning regardless of ship movement, we implemented a sophisticated feedback control system:

1. Sensor Fusion: Combined data from EnDat 2.0 encoders and inertial measurement units (IMUs) to accurately determine platform orientation.
2. PID Control: Connected with the Platform Controller which provided the feedback control using the encoders and the motors.

The End Result

Softwise Mechatronics successfully delivered the embedded solution within the specified time and budget constraints. Key achievements include:

1. Seamless Integration: The developed system efficiently converted messages between the proprietary RS485 protocol, EtherCAT, and EnDat 2.0 within the required time limits.
2. Robustness: Extensive testing confirmed the system's reliability in simulated maritime environments.
3. Client Satisfaction: The defense equipment manufacturer expressed high satisfaction with the solution, noting its performance exceeded their expectations.

This project showcases Softwise Mechatronics' expertise in embedded systems development, protocol integration, and advanced control systems. Our ability to navigate complex technical requirements while adhering to strict timelines demonstrates our value as a partner for sophisticated defense and industrial projects.