24.3. Architecture and Components of a Cobot System

• Lightweight arms with 6-7 degrees of freedom (DoF). • Use of soft or rounded edges for safety. • Compact actuators and flexible joints.

The mechanical structure of a collaborative robot (cobot) is designed to be lightweight and flexible, featuring arms that can move in 6 to 7 different directions (degrees of freedom). This flexibility allows cobots to perform a wide range of tasks. The arms are often designed with soft or rounded edges to prevent injury during accidental contact with humans. Additionally, compact actuators and flexible joints make cobots easier to maneuver in tight spaces, enhancing their capability to work alongside human operators effectively.

Consider how a human arm works: it can bend and rotate in many directions. A cobot's arms try to mimic this functionality, making them versatile. For instance, think of an artist painting a canvas. The lightweight, flexible structure allows the artist to reach various angles effortlessly. Similarly, cobots can reach into tight spots on a construction site without risking safety.

• Force-torque sensors for contact detection. • Vision systems for object recognition and navigation. • Proximity and LiDAR sensors for human detection and collision avoidance.

Cobots are equipped with various sensors that allow them to interact safely and intelligently with their environment. Force-torque sensors help the cobot detect when it makes contact with an object, ensuring that it can respond appropriately, such as stopping to prevent damage or injury. Vision systems enable the robot to recognize objects and navigate through complex environments. Additionally, proximity and LiDAR sensors help detect the presence of humans nearby, allowing the robot to avoid collisions and maintain a safe working distance, which is crucial for effective shared spaces.

Imagine a self-driving car that can see its surroundings and stop for pedestrians. Similar technology is used in cobots, making them aware of where people are and helping them to avoid accidents. This ensures that they can work alongside humans without causing danger, just like how a careful soccer player avoids colliding with teammates while running for the ball.

• Central controller for trajectory planning and task execution. • Integrated safety protocols (e.g., ISO 10218-1 and ISO/TS 15066). • Real-time response systems for dynamic environments.

The control system of a cobot acts as its 'brain,' managing how it moves and performs tasks. A central controller is responsible for planning the paths (trajectories) the cobot will take when executing tasks. This system incorporates safety protocols to ensure compliant operation within established safety guidelines. For instance, ISO standards outline requirements for safety in robot systems. Moreover, cobots need to be responsive in real-time as their environments can be dynamic, which allows them to adjust their movements based on changes around them, like a person dodging a ball during a game.

Think of a conductor leading an orchestra. The conductor plans how the music will be played and makes real-time adjustments to ensure everything sounds harmonious. Just as the conductor keeps track of each musician, the control system in a cobot ensures that it knows where to go and what to do, even when unexpected things happen around it.

• Custom-designed grippers, welders, drills, or suction cups depending on the task. • Tool changers for multipurpose functionality.

End effectors are the tools at the end of a cobot's arm that interact directly with the environment. These can be custom-designed for various tasks, such as grippers for picking up items, welders for joining materials, drills for making holes, or suction cups for lifting flat surfaces. Additionally, many cobots come with tool changers, which allow them to swap out one end effector for another, enabling a single robot to perform multiple functions on a job site. This flexibility is essential in construction, where different tasks might require different tools.

Consider a Swiss Army knife, which has multiple tools within one compact device. You can switch from a knife to scissors or a screwdriver based on what you need. Similarly, cobots can adapt by changing their end effectors to suit the task they're performing, whether it’s lifting, cutting, or welding, making them incredibly versatile on construction sites.

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