Page 113 - Toucpad robotics C11

Pan-and-Tilt Units: For precisely aiming cameras, sensors, or other devices (e.g., in surveillance robots, drone
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cameras).
Robotic Legs/Wheels (Advanced): In more complex legged robots or for steering mechanisms in wheeled robots
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where precise angle control is needed.
CNC Machines: For controlling the precise movements of cutting tools.
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Advantages
High Precision and Accuracy: Unmatched in their ability to achieve and maintain exact positions.
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Closed-Loop Control: Provides excellent accuracy and repeatability, even under varying loads.
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High Torque-to-Size Ratio: Can generate significant torque for their compact size due to gearing.
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Dynamic Response: Very responsive to changes in command, making them suitable for dynamic movements.
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Smooth Operation: Can operate very smoothly, even at low speeds, with minimal cogging (jerky motion).
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Reliable: Less prone to “losing steps” or position errors compared to open-loop motors.
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Disadvantages
Higher Cost: Generally, more expensive than basic DC motors due to the integrated electronics, gears, and
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feedback sensor.
Complexity: Requires more sophisticated control electronics and tuning to stabilise the feedback loop.
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Limited Continuous Torque: While they have high peak torque, they may not sustain high torque continuously
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without overheating, especially in hobby-grade servos.
Overload Sensitivity: Can be damaged by prolonged stalling or excessive loads if not properly controlled.
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Power Consumption (at rest): Even when holding a position, a servo motor continuously draws current to maintain
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that position against external forces.

AI Is Fuelling Self-Driving Cars
Self-driving cars, like those from Tesla or Waymo, rely on AI to “see” the road using
cameras, lidar, and radar. The AI processes this data in real time to recognise traffic lights,
BRAINY pedestrians, and other vehicles. The goal is to make driving safer by reducing accidents
FACT
caused by human error. While still under testing, self-driving cars could one day transform
transportation, making traffic jams less common and freeing up time that people usually
spend behind the wheel.

Comparison Summary (DC Motor vs. Servo Motor in Robotics)

Feature DC Motor (Typical Brushed) Servo Motor (Closed-Loop System)
Primary Use Continuous rotation, speed control Precise position, velocity, and torque control
Open-loop (speed by voltage/PWM (Pulse
Control Closed-loop (position/angle by feedback)
Width Modulation), direction by polarity)

Accuracy Lower (without external encoder) High (due to continuous feedback)
Motor, gearbox, position sensor, control circuit,
Components Motor, brushes, commutator
amplifier
Cost Generally lower Generally higher

Lower (especially if brushless DC motor is used
Maintenance Higher (brushes wear out)
internally)

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Electrical and Control Systems