Analogue computers are designed to process analogue data. Analogue data is continuous data that changes continuously and cannot have discrete values. We can say that analogue computers are used where we don’t need exact values always such as speed, temperature, pressure and current.
Analogue computers directly accept the data from the measuring device without first converting it into numbers and codes. They measure the continuous changes in physical quantity and generally render output as a reading on a dial or scale. Speedometer and mercury thermometer are examples of analogue computers.
Advantages of using analogue computers:
- It allows real-time operations and computation at the same time and continuous representation of all data within the rage of the analogue machine.
- In some applications, it allows performing calculations without taking the help of transducers for converting the inputs or outputs to digital electronic form and vice versa.
- The programmer can scale the problem for the dynamic range of the analogue computer. It provides insight into the problem and helps understand the errors and their effects.
Types of analogue computers:
- Slide Rules: It is one of the simplest types of mechanical analogue computers. It was developed to perform basic mathematical calculations. It is made of two rods. To perform the calculation, the hashed rod is slid to line up with the markings on another rod.
- Differential Analysers: It was developed to perform differential calculations. It performs integration using wheel-and-disc mechanisms to solve differential calculations.
- Castle Clock: It was invented by Al-Jarazi. It was able to save programming instructions. Its height was around 11 feet and it was provided with the display of time, the zodiac, and the solar and lunar orbits. This device also could allow users to set the length of the day as per the current season.
- Electronic Analogue Computer: In this type of analogue computer, electrical signals flow through capacitors and resistors to simulate physical phenomena. Here, the mechanical interaction of components does not take place. The voltage of the electrical signal generates the appropriate displays.