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    Sub-Micron  Resolution: For high-precision  applications like  semiconductor  manufacturing,  robots  often  need  to
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                      operate at sub-micron levels. This means they must be able to move in increments of less than one micrometre
                      (one-millionth of a metre). Such robots are used for tasks like placing microchips or inspecting tiny components.
                      Integrated Vision Systems: Integrated vision systems that allow for real-time adjustments based on visual
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                      feedback further enhance a robot’s effective resolution. The robot can ‘see’ a slight positioning error and correct
                      it on the fly, allowing it to perform tasks with a level of precision that exceeds the mechanical resolution of its
                      components alone.
                         Real-time Example: A robot sorting fruit on a conveyor belt uses a high-resolution camera. The camera can
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                         detect  a tiny  blemish  on an apple.  The robot’s  arm, while having a certain  mechanical  resolution,  uses  the
                         camera’s feedback to make minute adjustments in its grasp, ensuring it can precisely pick up and place the
                         apple without damaging it.

                  Accuracy
                  Accuracy is the ability of a robot to position its end-effector precisely at a desired location in three-dimensional space.
                  It measures how close the robot’s actual position is to the target position. A robot can have high resolution (it can make
                  very small movements) but low accuracy (it can’t get to the exact desired location). Accuracy is affected by factors like
                  mechanical imperfections, joint play, temperature, and gravitational forces.
                      Current Trends: Enhanced Calibration Techniques: To achieve better absolute accuracy, modern robotics relies on
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                      advanced calibration techniques. Calibration is a process where the robot is precisely measured to account for all of its
                      mechanical imperfections, such as link lengths, joint alignments, and gear backlash. This data is then used by the control
                      system to create a more accurate mathematical model of the robot, minimizing errors in each part of the robot arm.
                         Real-time Example: In a car factory, a robotic arm is used to drill holes for screws on a car’s chassis. The robot is
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                         initially calibrated using a laser tracker, which measures the exact position of the robot’s end-effector throughout
                         its workspace. This calibration data is then fed into the robot’s control software. Consequently, when the robot is
                         commanded to move to a specific drilling location, it can do so with much greater accuracy, ensuring the hole is
                         drilled in the correct spot.
                      Dynamic Error Compensation: In real-world applications, factors like temperature changes (which cause materials
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                      to expand or contract) or wear and tear on joints can degrade accuracy over time. Modern control systems use
                      dynamic error compensation to adjust for these factors. Sensors can monitor temperature, for example, and the
                      control system can apply corrections in real time to maintain a high level of accuracy.
                         Real-time Example: In a metal fabrication plant, a robotic arm is used for welding. The heat from the welding
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                         torch can cause the robot’s arm to expand slightly, leading to a loss of accuracy. The robot’s control system,
                         equipped with temperature sensors, can compensate for this expansion in real-time, ensuring the weld remains
                         in the correct position.
                      Feedback Mechanisms: High-end robots use sophisticated feedback mechanisms to maintain accuracy. Techniques
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                      such as laser-based tracking systems or external vision systems can measure the robot’s actual position and provide
                      real-time correction signals back to the control system. This ensures that the robot is constantly adjusting its position
                      to match the desired location.
                         Real-time Example: A surgical robot performing a delicate operation uses a laser-based tracking system to
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                         continuously monitor the position of its surgical instruments. This system provides real-time feedback to the
                         robot’s control unit, which makes minute adjustments to the instruments’ position to ensure they remain on the
                         intended trajectory, enhancing the surgeon’s precision.

                  Repeatability
                  Repeatability is a robot’s ability to return to a specific position under identical conditions repeatedly. It is a measure of
                  the consistency of the robot’s motion. Think of it as a robot’s ability to place a pen in the exact same spot on a piece of
                  paper over and over again, even if that spot is not exactly where you wanted it to be (that would be an accuracy issue).

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                  Touchpad Robotics - XI

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