HOVERCRAFT

Basic Principle

Has a hull.

Inside that lift motor provides pressure greater than atmospheric pressure.

Because of the pressure difference it lifts.

Friction gets reduce between ground and contacting surface.

At this friction even a small thrust is enough for forward motion.

Has a motor for providing thrust.

Has a mechanism to changing direction of motion.

uses

Mode of transport.

Military purpose.

How it works

HOVERING

Lift motor exerts pressure greater than atm pressure.

Due to pressure difference body of hovercraft floats.

This reduces friction and makes it easier for motion.

Importance of Skirt

It guides the air pushed by hovering motor to form a air cushion.

Must be flexible, untearable.

Conical mount distributes air into skirt.

THRUST

Provided by a thrust motor and a propeller.

Propeller has twisted blade and cuts the air perpendicular to its axis of rotation.

And forcefully pushes the air into one direction.

By newton’s third law body moves in other direction.

Centre Of Gravity

CG must be approximately known.

Knowledge of cg provides to cop up with toppling, spinning,turning problems.

Helps to distribute the weight for maintaining the smooth motion.

Direction changing mechanism

Thrust would be unidirectional.

two rudder mechanism,

Concentrator pipe mechanism.

Two prop mechanism.

DRAG

It must be reduced for smooth motion of hovercraft.

Extra assembled parts like servo motors, motor mount batteries, rudder stabiliser etc increases drag.

Aerodynamic shape of the model reduces drag.

Dynamics equations

1. Lift force = pressure diff. created by the motor x base hull area.

2.Newton’s third law used in thrust. F1= -F2

3.Torque principal used in the rudder to controlled motion.T= length of the servo arm x Force

4. Efficiency increases due to decrease in friction force.efficiency=output power/input power

PARTS

BODY/HULL

Made up of card board and 4x sheet.

Aerodynamically shaped.

Can sustain generated thrust by hovering.

Conical mount distribute air into hull.

Motors

Hovering motor and thrust motor-BLDC Motors.

Peripheral 4x sheet cover into hovering motor to prevent air leakage.

Servo motor for giving torque to rudder.

Motor Mount Provides safety to thrust motor in case of toppling and other

damages. Made up of cardboard.

Thrust concentrator

Pipe acts as nozzle.

Pushes air into backward direction forcefully.

Due to reaction of that body moves in forward direction.

Its movement is given by servo motors.

SKIRT

Used material of an umbrella.

Must be flexible.

Must be untearable.

Radio-Controller

3- cell Li-Po battery

Servo tester

Receiver

Thank you!

Submitted by-

R. Deekshit reddyPrashant maidaV. AnirudhTrilochan kumbhkar