Robots actuators and how they work.

 

actuators are parts of robots,they are used in converting Electrical signals from the controller into force or physical movement.so in this article I will brief the types of actuators used in making robots.

Actuators are known to converting signals into movements it can be in rotation or linear movement.

Types of actuators:

1.DC brushless motor:This actuators converts Electrical Current into rotation,it usually consists of a shaft and controlled by an external motor driver circuit.DC brushless motors consists of a permanent magnet and a coil wound on a soft iron material.

2.Hydraulic and pneumatic motors: They use pressure applied to air to cause a pull,they don't offer a push back four.

3.servos: it consists of a DC motor,a speed control circuit,shafts and gears.It has three pinout which are the power,ground and controll.

servos are used in precise movement and they can turn in some angle step by step.

4.stepper motor.They are hybrid of DC brushless motors and servo,There movement is highly precise,there are often used in CNC machines, writing machines and 3D printers.it consists of an encoder which measures how far and the speed of it rotation.

5.muscle wire:are thin, highly processed strands of a nickel-titanium alloy called Nitinol– a type of Shape Memory Alloy that can assume radically different forms or "phases" at distinct temperatures.How do Muscle Wires work?

At room temperature Muscle Wires are easily stretched by a small force. However, when conducting an electric current, the wire heats and changes to a much harder form that returns to the "unstretched" shape - the wire shortens in length with a usable amount of force. 

Create your own fun Muscle Wires Project and learn more about how the work. 

How much do Muscle Wires shorten?

Muscle Wires can be stretched by up to eight percent of their length and will recover fully, but only for a few cycles. However when used in the three to five percent range, Muscle Wires can run for millions of cycles with very consistent and reliable performance. 

How strong are Muscle Wires?

Large wires are stronger than small ones, and strength varies with diameter. The strength to expect from a wire when heated is shown by the Recovery Weight in the table below. 

The Deformation Weight indicates the amount needed to stretch a wire when cool - about one sixth the force exerted when the wire is heated. Our largest wire has over 110 times the strength of the smallest size, so you can easily match wire strength to your needs. 

What if I need more strength?

For more strength, use two or more wires in parallel. Thzzis gives you as much strength as needed, and still keeps the fast cycle times of smaller wires. 

How fast can Muscle Wires activate?

Muscle Wires contract as fast as they are heated - in one thousandth of a second or less. To relax, the wire must be cooled, which depends on the conditions surrounding the wire, and its size. Our new Flexinol HT series of wires has a higher transition temperature and cools up to 50% faster than the LT wires. The table below gives typical cycle rates for both LT and HT wires in still air. Moving air or immersing the wires in a fluid like a water/glycerine mixture can increase these by ten times or more. 

How long do Muscle Wires last?

When used in the three to five percent range under proper conditions Muscle Wires can run for millions of cycles. Often, other parts of a device will fail or need adjusting long before the Muscle Wire does. 

What are the advantages of Muscle Wires?

Compared to motors or solenoids, Muscle Wires have many advantages: small size, light weight, low power, a very high strength-to-weight ratio, precise control, AC or DC activation, low magnetism, long life, and direct linear action. 

These features let you create whole categories of amazing new devices that would be difficult or impossible with anything other than Muscle Wires. 

What are the keys to using Muscle Wires?

For longest lifetimes and best performance from your Muscle Wire devices, follow these key points:

Have good electrical and mechanical connections.

Protect the wire from overheating.

Protect the wire from overstraining

6.lineaer actuators:.linear actuator is an actuator that creates motion in a straight line, in contrast to the circular motion of a conventional electric motor . Linear actuators are used in machine tools and industrial machinery, in computer

peripherals such as disk drives and printers, in

valves and dampers , and in many other places where linear motion is required. Hydraulic or

pneumatic cylinders inherently produce linear motion. Many other mechanisms are uses to generate linear motion from a rotating motor

7.piezo Electric actuators:.The piezoelectric effect is a property of certain materials in which application of a voltage to the material causes it to expand. Very high voltages correspond to only tiny expansions. As a result, piezoelectric actuators can achieve extremely fine positioning resolution, but also have a very short range of motion. In addition, piezoelectric materials exhibit hysteresis which makes it difficult to control their expansion in a repeatable manner.

therefore actuators are use for converting signals from a micro controller into physical movements.Kindly drop a comment below if have have any  question or want me to cover some topics on this blog,thanks for reading.