What are Industrial Robots?
Industrial robots are autonomously-controlled systems comprising sensors, controllers, and actuators mounted on an articulated frame. These devices execute specific tasks and operations within a production or processing line. Running continually following a program that directs them to perform cycles of repeated movement. They reduce or eliminate human involvement to boost processing capacity, speed, and quality.
It is essential to differentiate collaborative robots (cobots) from more recent conventional industrial robots. Cobots, which have a top speed and a maximum amount of force they can exert, operate alongside a human operator. Thus ensuring safety for those working around them. They may also identify obstacles or people in their path and stop moving due to enhanced motor current sensing.
Industrial robots are mainly mechanical arms that can move in various directions and may program to do multiple jobs in different settings. For example, these business robots can do the following:
- In various stages, including vacuum and high-pressure chambers.
- In both spotless workspaces and abjectly filthy places.
- In hazardous locations, there is a risk of explosions, diseases, radiation, or other highly harmful dangers for people.
Robotic arms may include grippers explicitly designed for handling delicate and breakable things, while other robotic arms may have grippers capable of lifting and grabbing weights weighing several tons.
The purpose of Industrial Robots?
We can use Industrial robots for varieties of applications. They are:
Handling
Industrial robots are quick, strong, elegant, and sensitive, manipulating items as varied as car doors and eggs. Applications include picking and placing items from a conveyor line into packing and machine tending. In addition, the robot feeds raw materials into processing machinery, including injection molding machines, CNC mills, lathes, and presses.
Sorting
Robotic systems are employed for their basic pick-and-place functionalities and rapid monitoring in sorting procedures. Visual sensors detect variations in size, color, and shape, allowing robots to select and discard unusual objects. Electronics and pharmaceutical industries are amongst those that commonly rely on robotic sorting mechanisms.
Palletizing
Packing packed goods or corrugated cartons onto a pallet in a predetermined manner is known as palletizing. Robotic palletizers can create basic to complex layer patterns on the pallet to enhance its stability during transit. They are equipped with a fixed position or overhead gantry robot and custom components connecting with the load. The three main palletizing methods are inline or layer formation, depalletizing or unloading, and mixed cases.
Cutting
Robots operate laser, plasma, and water jet cutters due to their hazard. The robot is designed to follow hundreds of cutting pathways, producing more exact precision and flexibility in path following than most specialized cutting equipment.
Deburring
It is another feature of contemporary industrial robots. To deburr and smooth outcast or injection-molded components, the robot in this operation holds a spinning tool—typically a sanding drum, wire wheel, or carbide deburr tool—and moves along a pre-programmed route. The benefit of a robot for deburring is that the operator would typically be exposed to dust or debris during the operation. In addition, the smoothing between sections may be more consistent since a robot works repeatedly.
Finishing
For a consistently high-quality finish, multi-axis robots can grind, trim, fettle, polish, and clean practically any item made of any material.
Inspection
Robotic inspection systems can utilize optical sensors, proximity sensors, force transducers, ultrasonic probes and even machine vision systems to conduct inspection activities on components or assemblies. These measuring tools measure a product’s dimensions to guarantee uniformity and quality. NDT of welds, which involves the autonomous movement and control of ultrasonic probes or arrays, is yet another inspection that robots can perform.
Sealing and gluing
To apply sealant or glue, a robot must maintain a continuous bead of the sticky substrate while correctly following a path with adequate speed control. Robots are often employed in packaging procedures for the automated sealing of corrugated product boxes and sealing applications in the automotive sector to seal windows.
Spraying
Robots also do spray applications to reduce human touch since solvent-based paints and varnishes are flammable and dangerous. To simulate a human’s application method, paint robots often have small arms because they don’t have to lift much weight.
Welding
Robotic welding systems are commonly used in high-volume metal production processes, as well as auto manufacturing facilities. Growing market competition necessitates higher operating rates and superior product quality, necessitating more precise welding techniques. Industrial robots offer better control of several parameters, such as current, voltage, arc length, filler feed rate, weld rate, and arc travel speed, providing the ultimate benefit in welding.
Industrial Robots’ Main Components
The manipulator, controller, human interface, and power source are the four essential components of an industrial robot. A V5 Smart Motor moves the arm of the V5 Workcell, acting as an actuator, supplying the necessary force. Electric motors, pneumatic cylinders, and hydraulic cylinders can all provide power to the robot. The controller, the “brain” of the system, is located on the arm and functions by taking signals from the system, processing them, and then sending back the output.
A teach pendant or another human interface device can be used to control and program the arms, while the final component of the power supply feeds electricity to the robot’s controller and actuators, typically in the form of electrical energy.
Types of Industrial Robots
Categorizing of Industrial robots is based on the arrangement of their arms. For instance, the number and type of joints and linkages in a robotic arm can be varied to give rise to robots with various combinations. These can be classified into six distinct categories.
Cartesian Robot
A Cartesian robot comprises three prismatic joints that generate linear motion along each axis. However, the robot can still achieve circular motion through kinematic models that enable circular interpolation. Derived from the three-dimensional Cartesian coordinate system (X, Y, and Z axes), Cartesian robots are best suited for applications needing right-angle movement without angular transformations.
It may be built as a Cartesian robot to accommodate heavier loads compared to other robots, owing to its capacity to incorporate one or two prismatic joints at both ends. An example of a Cartesian robot is the Gantry machine, which adeptly picks up and places bulky palletized items.
SCARA Robots
Refing to the acronym SCARA (Selective Compliance Assembly Robot Arm or Selective Compliance Articulated Robot Arm), its three-axis (X, Y, and Z) motion combined with rational movement make it more adept than Cartesian Robots at lateral movements, typically faster, and simpler to integrate. We use SCARA robots in bio-medical applications, palletizing, and assembling.
Polar Robot
Polar robots, often called ‘spherical robots’, operate in three dimensions using the polar coordinates of r, θ, and φ. With a spherical range, rather than a rectangular prism-shaped work envelope, these robots have a range of motion with a radius equal to the distance between the nearest revolute joint and the EOAT along the connection. As a result, polar robots have the most significant reach for a given arm’s length compared to other kinds of robots. The connection of a second link via a prismatic joint increases the range further. Such broad reach makes polar robots the ideal choice for machine-loading applications.
Articulated Robots
An articulated robot’s mechanical structure and design replicate that of a human arm, with a twist joint linking the arm to the base. The arm contains two to ten rotational joints which serve as axes, providing a wider range of motion. Most articulated robots have four or six axes. Typical uses for these robots include assembly, arc welding, material handling, machine tending, and packing.
Cylindrical Robot
As its name implies, a robot with a cylindrical range of motion comprises one revolute joint and two prismatic joints. The revolute joint at the arm’s base allows the links to rotate about the robot’s axis, while the two prismatic joints modify the height and radius of the cylindrical work envelope. Compact designs lack the prismatic joint used to alter the arm’s radius, yet this single revolute, single prismatic joint arrangement may prove useful in straightforward pick and place procedures when the product supply is only available in one location.
Collaborative Robots
Cobots, or collaborative robots, can interact directly and safely with personnel in a shared workspace. Get to know the various kinds and models of collaborative robots here. Popular cobot uses are picking/placing, palletizing, quality assurance, and tending machines.
Delta Robots
By connecting an EOAT to a common base, a delta robot is composed of at least three joints. Three undriven universal joints attach the linkages to the EOAT, while the floor is connected via three prismatic or revolute-driven joints, providing the EOAT with four degrees of freedom. A fourth link or shaft is typically connected to the EOAT to enable rotation in systems that use prismatic joints. This allows to create a dome-shaped work envelope by the EOAT, allowing movement along all Cartesian axes and rotation around the vertical axis. The three driving joints move synchronously, making delta robots well-suited for fast pick-and-place operations.
Performance Specifications of Industrial Robots
When devising a robot, multiple aspects are taken into account. Primarily, it should fulfill the performance criteria for the intended purpose while adhering to the budget. Superior specs always enhance the product. However, the costs tend to rise exponentially.
Axis
The quantity of axes affects an industrial robot’s range of motion. The more range of motion, the more axes. Each axis moves in a particular way. From each axis’s center base position, the amount of movement is calculated.” A robot’s axis is its degree of freedom or the number of movable “joints.” By the number and positioning of its axes, one can ascertain the robot’s flexibility and functionality. Directly related to the number of motors in the robot, axes can range from one to ten or more.
Take into account the robot’s motion speed if your application has speed requirements. Each axis has a distinct velocity and measured in degrees per second. Additionally, consider the repeatability of the robot – its capacity to come back to the same position. When selecting precision applications, look for more precise repeatability values, often called plus or minus millimetric alterations.
Load Capacity
A robot’s load capacity refers to the weight it can lift, the force it can apply, and the maximum stress it can withstand. The capacity of robots varies depending on their sector, ranging from 0.5kg to 1000kg. In pick-and-place applications, these parameters are essential. Modern robots’ load capacities are based on their maximum payloads, taking into account the acceleration/deceleration of the payload and end effector to/from the robot’s maximum speeds. Thus, when selecting the end effector for a robot, carefully considering its weight is a must.
Work Envelope
Work envelope is the area that a robot. We can measure robot’s vertical reach from its base up. This helps figure out whether the robot is tall enough. And can measure the robot’s horizontal distance from its base to its fully extended “wrist.” This is useful for determining the width of the work envelope.
Accuracy and Repeatability
Two factors crucial for a robot’s optimal performance are accuracy and repeatability. For example, a robot’s ability to accurately reach a predetermined position or place its load, is known as accuracy. It is measured by determining the extent to which its end result matches the predetermined target.
SAFETY
Workcells and industrial robotic systems include safety equipment to keep associates secure. Barrier guarding, arc glare shields, separators, and fences are a few examples of physical guarding. Back-up measures such as light curtains or area scanners are deployed to provide additional protection if an associate exceeds the threshold barrier. Scientists use emergency stops to stop the robot instantly.
Cobots, or collaborative robots, are designed to safely and securely work alongside humans, with built-in speed and separation monitoring, controlled power and force, and safety-rated monitored stops. To ensure safety, projects should evaluate any changes to the work. When selecting a robot and implementing automation, consider key factors such as load, orientation, speed, travel, precision, environment, and duty cycle.
Controller Specifications
Each robot is operated and configured with a controller for its locations, speeds, and clamped or unclamped grippers. Robots from various manufacturers use different programming techniques. For instance, some controllers support “teach through” programming, which requires moving the robot to multiple positions, “recording,” and then utilizing the position in the program. Most controllers also allow creation of structured or sequenced code, similar to “C” or BASIC programming, and involve creating a series of actions or I/O operations to perform a task.
Conclusion
In conclusion, robotics is a diverse sector with many moving parts, and its future is complex. Industrial robotics uses complex pre-programmed mechanisms for manufacturing or other industrial processes, including assembly, packing, labeling, painting, inspection, testing, welding, and more. Robots for these tasks provide high endurance, precision, and speed without much human intervention. The COVID-19 pandemic has “accelerated the use of robotics beyond established practice as industries had to consider keeping their operation up and running without human presence. This trend will likely continue in the foreseeable future.