BOOK_CONTENT
From Robotics

An actuator is the mechanism by which an agent acts upon an environment. The agent can be either an artificial intelligent agent or any other autonomous being.

The common forms of actuators are pneumatic, hydraulic, or electric solenoids or motors.

Pneumatic actuators: A simplified diagram of a pneumatic actuator is shown in Figure 3.49 below. It operates by a combination of force created by air and spring force. The actuator positions control the valve by transmitting its motion through the stem.

A rubber diaphragm separates the actuator housing into two air chambers. The upper chamber receives a supply of air through an opening in the top of the housing.

The bottom chamber contains a spring that forces the diaphragm against mechanical stops in the upper chamber. Finally, a local indicator is connected to the stem to indicate the position of the valve.


Pneumatic actuator: air-to-close/spring-to-open

FIGURE 3.49   Pneumatic actuator: air-to-close/spring-to-open.

The position of the valve is controlled by varying the air supply pressure in the upper chamber. This results in a varying force on the top of the diaphragm. Initially, with no air supply, the spring forces the diaphragm upward against the mechanical stops and holds the valve fully open. As air...


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Products & Services
Stepper Motors (rotary)
Stepper motors use a magnetic field to move a rotor in small angular steps or fractions of steps. They provide precise positioning and ease of use, especially in low acceleration or static load applications.
DC Servomotors
DC servomotors are generally small and powerful for their size, and easy to control. Common types of DC servomotors include brushless or gear motors.
Tactile Pressure Sensors
Tactile pressure sensors are used to detect the pressure distribution between a sensor and a target.
Capacitors
Capacitors are electronic components used for storing charge and energy. In their simplest form, capacitors consist of two conducting plates separated by an insulating material called the dielectric.

Topics of Interest

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