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Feature DC Motor (Typical Brushed) Servo Motor (Closed-Loop System)
Complexity Simpler More complex (requires tuning)
Requires continuous power and can drift Can hold position precisely, constantly
Holding Position
without a brake correcting for external forces

Often limited (e.g., 0-180 degrees), but
Typical Range Continuous (360 degrees+)
industrial types can be continuous
The choice between a DC motor and a servo motor in a robotic application depends entirely on the specific requirements
of the task. If a robot needs simple continuous movement, like driving its wheels forward, a DC motor (often with a
gearbox) might suffice due to its simplicity and cost-effectiveness. However, if the robot needs to perform highly accurate
and repeatable movements, such as precisely placing a component on a circuit board or articulating a robotic arm to a
specific angle, then a servo motor, with its inherent precision and closed-loop control, is the indispensable choice. These
actuators are the fundamental building blocks that allow robots to physically interact with and manipulate their world

Industrial Robot Goes Berserk
In a Chinese factory, workers were testing a new human-sized robot when a small coding
error made it go wild—swinging arms, kicking over a computer, and frightening engineers into
a sprint for safety. The error was traced to a misplaced decimal point in the code.

actual funny Learning: Attention to detail in programming is essential. Tiny mistakes can have big
incidents consequences—and sometimes, robot arms flying.

Sensors in Robotics: The Robot’s Perception

Sensors are indispensable components of any robotic system. They are transducers that convert physical phenomena
(like light, sound, touch, distance, motion) into measurable electrical signals that the robot’s control system can interpret.
Without sensors, a robot would operate blindly, unable to react to its surroundings or even know its own orientation. The
careful selection and integration of various sensors are critical for a robot’s ability to perceive, navigate, and interact with
the world effectively.

Let’s explore some of the most common and important types of sensors used in modern robotics:
Infrared (IR) Sensors

Description
An Infrared sensor is a device that detects infrared radiation. Infrared
radiation is a type of electromagnetic radiation, just like visible light, but
with a longer wavelength, making it invisible to the human eye. In robotics,
these sensors typically consist of an infrared Light Emitting Diode (LED) as an
emitter and an infrared photodiode or phototransistor as a receiver.
Working Principle

The infrared Light Emitting Diode emits a beam of infrared light.
u
If there is an object in front of the sensor, this infrared light reflects off the object.
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The infrared photodiode (receiver) detects the reflected infrared light.
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The amount of reflected light detected by the receiver changes based on the distance to the object, its colour, and its
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surface properties (e.g., reflective or absorbing). A shorter distance or more reflective surface usually means more
reflected light.

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