Page 110 - Toucpad robotics C11

The Toppling Bot Tournament
At a global robotics competition, a hopeful team wheeled out their robot for its big moment.
The bot spun, wobbled, and—clank!—fell off the stage, splitting into pieces. Instead of quitting,
the team rebuilt it overnight. The next day, their patched-up bot won a side prize for “Best
Comeback.”
actual funny
incidents Learning: Every failed experiment teaches resilience and creativity.

DC Motors (Direct Current Motors)
Brushes
Rotor Coils
Commutator

Stator Magnets
Shaft

Description and Working Principle
Description: A DC motor is an electrical machine that converts Direct Current (DC) electrical energy into mechanical
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energy, typically in the form of rotational motion. They are widely used due to their simplicity, reliability, and ease
of control
A basic Direct Current motor consists of two main parts: a stationary part called the stator and a rotating part called
the rotor (or armature).
The stator typically contains permanent magnets or electromagnets that create a stationary magnetic field.
The rotor is a coil of wire wound around an iron core, which is connected to a power supply through components
called brushes and a commutator.
How it works: The basic principle of a DC motor is based on the interaction between a magnetic field and a current-
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carrying conductor. When direct current flows through the rotor’s coils, it generates its own magnetic field. This
magnetic field interacts with the magnetic field of the stator. The attraction and repulsion between these magnetic
fields create a turning force called torque, which causes the rotor to spin continuously. The commutator and brushes
work together as a mechanical switch, continuously reversing the direction of current in the rotor coils to maintain
continuous rotation in one direction.
There are variations like Brushed Direct Current motors (which have brushes and commutators) and Brushless
Direct Current motors (which use electronic commutation instead of physical brushes, offering greater efficiency
and longevity).

Characteristics
Continuous Rotation: DC motors provide continuous rotational motion as long as power is supplied.
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Speed Control: Their speed can be easily controlled by varying the input voltage. Higher voltage generally means
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higher speed. A common method for precise speed control is Pulse Width Modulation (PWM), where the voltage is
rapidly switched on and off, with the “on” time determining the average voltage.
Torque: They can provide high starting torque, meaning they have good initial pulling or turning power.
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Simplicity: Brushed DC motors have a relatively simple construction.
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Touchpad Robotics - XI