Page 157 - Toucpad robotics C11

Principle: Each propeller creates thrust (an upward force) by pushing air downwards. The drone’s flight controller
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independently adjusts the speed of each motor.
Movement Control:
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To lift off or ascend, all propellers speed up, increasing total thrust.
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To descend, they slow down.
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To move forward/backward (pitch), propellers on one side speed up while those on the opposite side slow
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down, tilting the drone.

To move sideways (roll), propellers on the left speed up while those on the right slow down, tilting the drone.
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To turn left/right (yaw), specific pairs of propellers speed up or slow down to create a rotational force.
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Advantages: Capable of vertical take-off and landing (VTOL), stable hovering, high maneuverability, and
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easier to control for beginners.
Disadvantages: Limited flight time (battery life), slower forward speed compared to fixed-wing, sensitive to wind.
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Fixed-Wing Drones:
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Description: Resemble small aeroplanes with wings. They use
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a single or multiple propellers for forward thrust and rely on
the airflow over their wings to generate lift.
Principle: Similar to aeroplanes, they require forward motion
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to generate lift over their wings. Control surfaces (ailerons,
elevators, rudder) are used to steer and change altitude.
Advantages: Much longer flight times and greater range (more energy efficient at cruising speed), can carry
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heavier payloads for longer distances.

Disadvantages: Requires a runway or launch system for take-off and landing (cannot hover or do vertical
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take-off/landing), less maneuverable, more complex to operate.
Hybrid Drones (Fixed-Wing VTOL):
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Description: Combine features of both, offering vertical take-off and landing with the efficiency of fixed-wing flight.
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Advantages: Best of both worlds – vertical take-off/landing in confined spaces and efficient long-duration flight.
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Disadvantages: More mechanically complex and expensive.
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Control System and Stability

Flight Controller (The Brain): An onboard computer that runs sophisticated algorithms to continuously monitor the
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drone’s orientation, altitude, and position using various sensors. It then sends precise commands to the motors to
maintain stable flight or execute commanded movements.
Sensors for Stability and Navigation:
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Inertial Measurement Unit (IMU): Contains gyroscopes (to measure rotational rates and prevent unwanted
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spinning) and accelerometers (to measure linear acceleration and determine tilt/orientation relative to gravity).
This is absolutely critical for maintaining stable flight.
Barometer: Measures atmospheric pressure to estimate altitude.
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Global Positioning System (GPS): Provides precise outdoor location, speed, and altitude data, enabling
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autonomous navigation between waypoints.
Magnetometer (Electronic Compass): Measures the Earth’s magnetic field to determine the drone’s heading
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(direction), similar to a compass.

Vision Sensors (Cameras): For visual odometry (tracking movement by observing visual features), obstacle
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avoidance (identifying objects), and landing assistance (recognising landing pads).

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Applications of Robotic Systems