SysML (Systems Modeling Language) is a visual modeling language used for system engineering to capture and define the structure, behavior, and properties of complex systems. IBD (Internal Block Diagram) and BDD (Block Definition Diagram) are two types of diagrams in SysML that are commonly used to represent the internal structure and composition of a system. Let's break down what each of these diagrams is and provide examples for an AMR (Autonomous Mobile Robot) system equipped with LIDAR, IMU (Inertial Measurement Unit), and wheel encoders.

**1. Block Definition Diagram (BDD):**

A Block Definition Diagram (BDD) is used to define the types of blocks or components in a system and their interrelationships. It provides an overview of the major system components and how they relate to one another. In your case, the BDD for an AMR robot might look like this:

- **Robot**: This is the top-level block representing the entire robot.

  - **LIDAR**: A sub-block representing the LIDAR sensor.
  
  - **IMU**: A sub-block representing the IMU sensor.
  
  - **Wheel Encoders**: A sub-block representing the wheel encoders.

  - **Wheels**: A sub-block representing the wheels of the robot.
  
  - **Control Unit**: A sub-block representing the robot's control unit.
  
The arrows or connectors between these blocks indicate relationships and associations. For example, you would have connectors from the "Robot" block to "LIDAR," "IMU," "Wheel Encoders," "Wheels," and "Control Unit" to show how these components are part of the robot.

**2. Internal Block Diagram (IBD):**

An Internal Block Diagram (IBD) is used to show the internal structure of a particular block or component and how its internal parts are interconnected. In the case of your AMR robot, let's create an IBD for the "Robot" block:

- **Robot (IBD)**:

  - **LIDAR (Sensor)**: This is the LIDAR sensor within the robot.
  
  - **IMU (Sensor)**: The IMU sensor within the robot.
  
  - **Wheel Encoders (Sensors)**: These represent the wheel encoders inside the robot.
  
  - **Wheels (Components)**: The wheels of the robot.
  
  - **Control Unit (Component)**: The control unit or controller of the robot.
  
You can use connectors or ports to indicate how these internal components are connected or communicate with each other. For example, you might have connectors from the LIDAR to the Control Unit to show that LIDAR data is processed by the control unit. 

In both diagrams, you can specify attributes, operations, and interfaces associated with each block or component to provide more detailed information about the system. These diagrams help system engineers and stakeholders understand the system's architecture and how different components interact to achieve the desired functionality. The specific details of your diagrams may vary based on the robot's actual design and system requirements.


Examples:
https://www.intechopen.com/chapters/24651
