Automation and Applications of Industry 4.0 Technologies

The notion of putting machines to work for us and perform routine tasks on command can be credited long way back to great thinkers like Aristotle. His disciple “Alexander the great” went on to conquer the world but Aristotle had already conquered the world with his philosophies.

This lecture debates on the pros & cons of robotics & AI.

According to “Robot Institute of America” – A robot is a re-programmable, multi-functional manipulator designed to move material, parts, tools or specialized devices through variable programmed motions for the performance of a variety of tasks.

In simpler terms - A robot can be defined as a mechanical device that is capable of performing a variety of tasks on command or according to instructions programmed in advance.

Issac Asimov, a sci-fi writer during 1970 in a story titled “Runaround”, Coined the word “robotics” and proposed 3 “Laws of robotics”.

Law 1 – A robot may not injure a human being or through action, allow a human being to come to harm.

Law 2 – A robot must obey orders given to it by human beings, except those orders contains anything that can harm humans.

Law 3 – A robot must protect its own existence as long as such protection does not violate Law 1 & 2.

Issac Asimov later added one more law called “Zeroth law of robotics” – Which says, A robot may not injure humanity or through inaction, allow humanity to come to harm.

A typical robotic system comprises of a Manipulator linkage, End effector, Sensors, Actuator, Controller system, Feedback system & a Computer Interface.

1. Based on mechanical configuration:

• Cartesian coordinate configuration

• Cylindrical configuration

• Polar configuration

• Revolute or Jointed arm configuration

2. Based on control method:

• Non-servo controlled

• Servo controlled

3. Based on actuators used:

• Electric

• Hydraulic

• Pneumatic

Degrees of freedom, in a mechanics context, are specific, defined modes in which a mechanical device or system can move. The number of degrees of freedom is equal to the total number of independent displacements or aspects of motion.

A typical robot requires 6 DOF in 3D space. The first three joints help in reach and the other three joints are in the wrist for orientation. However, the configuration is based upon first three joints only viz for the joints helping in the REACH of the robot.

Now, as per the robotic configuration is concerned corresponding to the reach or the first three joints in the robot, we have – Rectangular or Cartesian, Cylindrical, Articulated, & Spherical/Polar configurations.

Some robots are also there which contains a mix of different configurations, like Gantry robot, SCARA robot, Delta robots & Collaborative robots. They have huge impact in many sectors as per time, cost of production and efficiency is concerned. I call them – “The white-collar robots”

For many years, Machine tools have been operated by skilled machinists. Judgement about their speed, tool configuration, feed rate etc was done by the machinist. The quality of the product machined depended upon his craftsmanship, knowledge & skills. It was almost impossible for two different operators to produce identical products. In fact, even one operator cannot produce identical products successively. The complex shapes of aircraft industry were not at all possible by manual methods.

It all changed during a machine-tool-exhibition in Chicago in 1960. Where almost a 100 NC machines were displayed which gathered attention of many industrialists of that time & NC machines became part of our manufacturing sector.

The CNC machine has an added feature of an onboard computer called Machine Control Unit or MCU in short.The machine functions are coded into the computer ROM at the time of manufacture and they do not get erased when the machine is turned off.

The main components of CNC are – Part programme, Input device for part programme, MCU (Machine Control Unit), Drive system, Machine tool, Feedback system & Display unit.

Point-to-point CNC machines are based on motion. They are also known as continuous path CNC machines. In this system, the tool & workpiece are held at a particular location, while the tool does the operation (drilling for instance). After the completion of the operation, the tool or the workpiece is moved to the next position of operation.

Incremental system

In this system, the distances are measured from one point to the next point.

Absolute system

In this system the movement commands are with reference to origin.

Open -loop system

Here the command for movement of the slides are given to the stepper motor.

Closed-loop system

The closed-loop system is provided with feedback system. The feedback loop gives the information about the error in the position reached.

Two axes machines have movements along two axes as in lathe.In 3-axes machines, there will be one more axis, perpendicular to the above two axes.

Milling CNC centres have 2 more motions in addition to the x, y, z motions. The rotary motion of the spindle and the rotary motion of the index table. Such machinery is what we call a higher axes machine. The 5-axes milling centre is a more popular version. The real value of CNC can be found within higher axes machining. This is such a method that can never be accomplished by manual means.

Word address is the most common programming format used for CNC programming systems. This format contains a large number of different codes that transfers program information from the part print to machine servos, relays, micro switches etc. to manufacture the part. These codes are in a logical sequence called block of information. Each block should contain enough information to perform one machining operation.

Every program in any part to be machined must be put in a format that the MCU can understand. The format used on any CNC is built in by the machine tool builder and is based on the type of control unit on the machine. A variable-block format which uses letters is most commonly used. Numerical data follows this address to identify a specific function such as distance, feed rate, or speed value.

The most common codes used for programming CNC machine tools are G-Codes & M-Codes. G codes are for preparatory functions & M codes are for miscellaneous functions. Other codes such as F, S, D & T are used for machine functions such as feed, speed, cutter diameter offset, tool number etc.

The best way to really get a grasp of how coding works in CNC is to write a full program so we're going to do that with a simple part that has got a few straight lines and a few radiuses and very simple measurements but it will give us an idea of how these G codes and M codes work within a program. Please see the complete coding below;

(2021);

(T3 D=16.0 – FLAT END);

G90 G94 G91.1 G40 G49 G17 G21;

M05;

M09;

T3 M06;

S12000 M03;

G54;

G41 D3;

G43 Z15. H3;

M08;

G00 X0.0 Y-20.0;

Z5.0;

G01 Z-5.0 F250.0;

Y160.0 F300.0;

G02 X20.0 Y180.0 I20.0 J0.0;

G01 X160.0;

G02 X180.0 Y160.0 I0.0 J-20.0;

G01 Y40.0;

G02 X140.0 Y0.0 I-40.0 J0.0;

G01 X-20.0;

G00 Z15.0;

X240.0 Y240.0 M09;

M05;

G40;

M30;

CNC machining is a versatile and cost-effective manufacturing process. This process is compatible with a huge range of materials. CNC machining helps across a diverse array of industries for a variety of applications. Manufacturers and machinists use this process in various ways. This includes direct manufacturing process, indirect manufacturing process, or in conjunction with other processes.

It is widely believed that 3D printing or additive manufacturing (AM) has the vast potential to become one of these technologies. There is a lot of coverage on 3D printing across many television channels, newspapers and online resources. Now What really is this 3D printing that some have claimed will put an end to traditional manufacturing as we know it? Revolutionize design and impose geopolitical, economic, social, demographic and environmental and security implications to our everyday lives.

The entire 3D printing technology can be divided into 3 steps –

(a) 3D Design

(b) Slicing

(c) 3D Printing.

3D digital model is the starting point for any 3D printing process. This digital model can be created using various 3D design software like Fusion 360 & Solidworks or can also can be created using 3D scanning. Once the 3D model is created, it is then sliced into layers thereby converting the design into a file readable by 3D printer. This slicing is done by exporting 3d model to another software like Ultimaker cura. 3D printer will then print this file layer by layer using the material given as input to the 3D printer.

Stereolithography (SL) is widely recognized as the first 3D printing process. It was certainly the first to be commercialized. SL is a laser-based process that works with photopolymer resins that react with the laser and cure to form a solid in a very precise way. It is a complex process but simply put the photopolymer resin is held in a vat with a movable platform inside.

DLP (Digital Light Processing) is a similar process to stereolithography in context that it is a 3D printing process that works with photopolymers. The major difference is the light source. DLP uses a more conventional light source, such as an arc lamp with a liquid crystal display panel, which is applied to the entire surface of the vat of photopolymer resin in a single pass, generally making it faster than SLA.

Laser sintering and laser melting are interchangeable terms that refer to a laser-based 3D printing process that works with powdered materials. The laser is traced across a powder bed of tightly compacted powdered material, according to the 3D data fed to the machine, in the X-Y axes. As the laser interacts with the surface of the powdered material it sinters, or fuses, the particles to each other forming a solid. As each layer is completed the powder bed drops incrementally and a roller smoothens the powder over the surface of the bed prior to the next pass of the laser for the subsequent layer to be formed and fused with the previous layer.

3D printing utilizing the extrusion of thermoplastic material is easily the most common and recognizable 3DP process. The most popular name for the process is Fused Deposition Modelling (FDM). However, this is a trade name, registered by Stratasys, the company that originally developed it. Stratasys’ FDM technology has been around since the early 1990’s and today is an industrial grade 3D printing process.

Binder jetting: Where the material being jetted is a binder, and is selectively sprayed into a powder bed of the part material to fuse it a layer at a time to create/print the required part. As is the case with other powder bed systems, once a layer is completed, the powder bed drops incrementally and a roller or blade smoothens the powder over the surface of the bed, prior to the next pass of the jet heads, with the binder for the subsequent layer to be formed and fused with the previous layer.

Material jetting: a 3D printing process whereby the actual build materials (in liquid or molten state) are selectively jetted through multiple jet heads (with others simultaneously jetting support materials). However, the materials tend to be liquid photopolymers, which are cured with a pass of UV light as each layer is deposited.

SDL is a proprietary 3D printing process developed and manufactured by Mcor Technologies. The SDL 3D printing process builds parts layer by layer using standard copier paper. Each new layer is fixed to the previous layer using an adhesive, which is applied selectively according to the 3D data supplied to the machine. This means that a much higher density of adhesive is deposited in the area that will become the part, and a much lower density of adhesive is applied in the surrounding area that will serve as the support, ensuring relatively easy “weeding,” or support removal.

The Electron Beam Melting 3D printing technique is a proprietary process developed by Swedish company Arcam. The heat source is an electron beam, rather than a laser, which necessitates that the procedure is carried out under vacuum conditions.

The materials available for 3D printing have come a long way since the early days of the technology. There is now a wide variety of different material that are supplied in different states (powder, filament, pellets, granules, resin etc.)

Specific materials are now generally developed for specific platforms performing dedicated applications (an example of such dedicated application would be the dental sector). In this lecture, we shall look at the most popular types of generic materials available for 3d printing.

The origins of 3D printing in ‘Rapid Prototyping’ were founded on the principles of industrial prototyping as a means of speeding up the earliest stages of product development. Prototyping is still probably the largest application of 3D printing today.

The developments and improvements of the process and the materials since the emergence of 3D printing for prototyping saw the processes being taken up for applications further down the product development process chain. Tooling and casting applications were developed utilizing the advantages of the different processes. Again, these applications are increasingly being used and adopted across industrial sectors.

Do not forget to see the BONUS LECTURE to receive complete course notes.

So with this.We conclude our course.I hope you understood everything well and will apply the same.Remember! you have a lifetime access to the course and you can always ask for anything in the Q/A section.Do not forget to leave a review and download completion certificate.

The complete course material in PDF format is attached herewith.

All the very BEST !!