The Core Disciplines
The three pillars required to design and control any automated system.
1. Kinematics & Dynamics
The study of motion without (kinematics) and with (dynamics) considering forces. This is crucial for designing the structure and calculating joint movements.
- Forward/Inverse Kinematics
- Degrees of Freedom (DOF)
- Singularities and Workspace
2. Sensing & Perception
How the robot perceives its environment. Choosing the right sensors (visual, tactile, positional) determines the system's ability to react.
- Vision Systems (Lidar, Cameras)
- Encoders and Limit Switches
- Haptic Feedback
3. Control Theory
The algorithms used to stabilize and guide the robot's motion. Includes open-loop timing and closed-loop feedback systems like PID controllers.
- PID Control Loops
- Trajectory Planning
- Real-time Operating Systems (RTOS)
Essential Components for Builders
The critical hardware needed to bring digital designs to life.
Actuation Systems
Motors are the muscles of the robot. Selection depends on required torque, speed, and precision.
- **Stepper Motors:** High precision for open-loop positioning (e.g., 3D printers).
- **Servos:** Integrated control for defined angular positions.
- **Brushless DC (BLDC):** High power-to-weight ratio, requires external driver.
- **Gearing:** Planetary or cycloidal systems to increase output torque.
Microcontrollers & SBCs
The brains of the robot, executing code and processing sensor data.
- **Arduino/ESP32:** Excellent for simple control and real-time sensor processing.
- **Raspberry Pi:** Single Board Computers (SBCs) for heavier tasks (Vision, ROS).
- **Motor Drivers (DRV8825, SimpleFOC):** Bridge between the controller and the motor.
- **ROS (Robot Operating System):** Middleware for complex, modular robotic software architecture.
Case Study: The 5-Axis Printed Arm
A deep dive into the mechanical and software challenges of our recent project.
Mechanical Design Highlights
- **3D Printed Structure:** Designed for stiffness using PETG/Nylon and large fillets.
- **Strain Wave Gearing:** Used to achieve high reduction ratios with minimal backlash at joints.
- **Modular End Effector:** Quick-change flange for swapping grippers and tools.
Control System & Software
- **Microcontroller:** ESP32 for high-speed calculation and motor command.
- **Programming:** Custom C++ kinematics solver to ensure accurate point-to-point movement.
- **Control Interface:** Web interface hosted on the ESP32 for jogging and saving positions.
- **Safety Features:** Software limits and current sensing for stall protection.
Advanced Topics
Areas of ongoing development in the robotics community.
Simulation (Gazebo/CoppeliaSim)
Testing control logic and path planning in a virtual environment before deployment.
Machine Learning for Vision
Using neural networks (e.g., YOLO) for object recognition and pose estimation.
Force Control
Enabling the robot to interact gently with its environment (e.g., assembly, polishing).