By

Gokul Lakshmanan

Introduction.

Objective.

Working principle.

Purpose.

Cost of production.

Conclusion.

Reference.

Gyrocompass is a type of non-magnetic compass.

One important component of a gyrocompass is a gyroscope, but these are not the same devices.

To construct a Gyrocompass.

Gyrocompass consist of a spinning wheel mounted on gimbal so that the wheel's axis is free to orient itself in any way.

When it is spun with its axis pointing in some direction, such a wheel will maintain its axis of rotation.

A gimbal is constructed in such a way that no external torque acts on the axis of rotation of gyro.

BASIC COMPONENTS

a) For Navigation

b) To Stabilize Airplane and Ship

For assisting navigation the axis of rotation of gyro is aligned to point towards the geographical north.

Since no external torque acts on the axis of rotation the gyro will always point towards geographical north irrespective of the motion of ship

A marine gyrocompass

A Gyrocompass is mounted on Airplane or Ship.

Variation in alignment of gimbal frame w.r.t axis of rotation of gyro is used judge the amount of pitch, roll and yaw experienced by Airplane or ship.

The degree of pitch , yaw or roll experienced by the ship is measured and converted into electrical signal by a transducer which is then send to the pilot or captain of the ship.

Advantages: Disadvantages

Seeks geographic (true) north instead of magnetic.

Gimbal lock occur when two axis align parallel to each other.

Can be used near the earth’s magnetic poles, where magnetic compass is useless.

Requires a constant source of electrical power and is sensitive to power fluctuations.

Unaffected by surrounding metals.

Requires periodic maintenance by qualified technicians.

COMPONENT SPECIFICATIONS

DISCa. DIAMETER = 178.8 mm.b. MASS = 1.5 kg.

BALL BEARINGa. DIAMETER = 19.5 mm.b. Nos. = 6

PIPE (G I)a. DIAMETER = 19.5 mm.b. LENGTH = 6 m.

Make a 3 axis gimbal and provide necessary joints to mount the gyro.

Attach the gyro to the gimbal and provide sufficient rpm

Align the gyro axis pointing a specific direction, say North.

Test the instrument by providing torque on frames of gimbal.

For a rotating gyro with mass ‘M’ and radius ‘r’.

Angular momentum is given by:𝐿 = 𝑀 ∗ 𝑣 ∗ 𝑟

Where ‘𝑣’ is the tangential velocity of gyro.

The value of angular momentum should be large enough to oppose any torque which the gyro experience due to self-weight.

Component Specification Cost (Rupees)

Bearing 6.nos 300

Disc 1 100

G I Pipe 6meters 440

Nuts and Bolts 8.nos 30

Transportation 200

Paint 3 Bottles 278

TOTAL 1348

A 3-axis Gimbal gyrocompass is constructed and is tested for accuracy.

Gyrocompass - Wikipedia, the free encyclopedia

Gimbal - Wikipedia, the free encyclopedia

YOUTUBE: MIT Open Course Ware Lec. 24 | 8.01 Physics I: Classical Mechanics, Fall 1999