Computer Numerical Control

Ever since the industrial revolution started, the demand to create precise instruments and products is an important factor in large scale manufacturing. Belts, screws, Drills and all movable parts needed to create other products in the assembly line must all be exact and compatible, thus extra care must be taken in order to ensure that all moving parts match perfectly. Computer Numerical Controlled programming has become an extremely important part of this process.

Computer Numerical Controlled Machines are useless without any programming. CNC’s rely on pure hard codes in order to execute commands that the Machine Operator wants to do, therefore not only is it needed to learn the mechanics of the whole Computer Numerical Controlled Machine but it is also at the utmost importance that the Machine operator knows how to communicate with the machine, and that is by using G-codes.

Preparatory code/ functions or much commonly called as G-codes are functions in the Computer Numerical Control programming language. The G-codes job is to manage the position of the tool as well as control the step by step commands during the actual work. Basically the G-codes are the most important part of the Computer Numerical Control Programming algorithm.

There are other codes involved in the programming of CNC’s such as M-codes that manages the machine, T-codes for managing the tools, and F-codes for the tool feed and tool speed controls. All of these codes are created in a Computer Aided Manufacturing (CAM) software.

G codes as well as the others use the RS-274D as the recommended standard for the Computer Numerical Controlled Machines. This standard was developed by the Electronic Industry association during the 1960’s. These standards provide a basis for the creation of Computer Numerical Controlled Programs.

First designs of these standards came from punched paper tapes as the medium standard for data interchange, but now ASCII character bit patterns are the standard for the representation.

G-Codes

Lets discuss the g-codes further, as what I have said earlier G- codes constitute only a part of the Computer Numerical Control Program, in the whole programming algorithm, they are denoted by the letter G, Basically it is a code telling the machine what kinds of actions to perform in a step by step basis, examples of these actions would be rapid move, controlled feed moves that would bore holes, a work piece cut routed to a specific dimension, change a pallet, and set a tool information such as offset.

After creating each part of the codes, the algorithm is compiled in the Computer Aided Manufacturing (CAM) software. The CAM software basically use translators called post processors to output the code optimized for a certain machine type. Often times, post-processors are often used to allow users to enable further customization.

G-codes can also be used to create outputs for Computer Aided Design systems used to design printed circuit boards (PCB). Any software must be customized for each type of machine tool that it will be used to program. Some G-codes are written by hand for volume production jobs.

Some Computer Numerical Controlled machines use conversational programming. Conversational programming is an easier way to program CNC machines because it is more “user friendly” because it uses a wizard like program that hides the G-codes into plain view. Some Popular examples of this kind of CNC machines are the Southwestern Industries’ Proto TRAK, Mazak’s Mazatrol, and Mori Seiki’s CAPS conversational software.

Conclusion

With these kinds of further sophistication in programming Computer Numerical Controlled Machines, it is expected in the future that programming would be much easier for its machine operators.

Have you ever asked yourself how machines in a factory know exactly when to stop making the parts they’re supposed to make? Well, this is all because of Computer Numerical Control (CNC). But to understand CNC, you have to know what Numerical Control (NC) is.

HISTORY

NC machines were first introduced after the 2nd world war as mass production became the trend. These machines were given a set of instructions in punched cards. However, these machines were hard-wired and their parameters were difficult to change.

These NC machines still required a great deal of human intervention. To illustrate this point, try to take a look at a drill press. A lot of actions have to be taken in order to manufacture a product. The process is actually so complicated that a person has to do something almost every step of the production process. This created an avenue for errors to take place as the likelihood of fatigue increased with the quantity growth.

CNC then came into the picture when computers were introduced. Punched cards were replaced by floppy disks, cables, and other software transfer media. This made it easier to manage and edit data.

Production and manufacturing were revolutionized by the increased automation of CNC machines. These machines allowed a degree of added control over the quality and consistency of the components that were manufactured without any additional strain on the operators. This reduced the frequency of errors and allowed the operators time to perform additional tasks. Furthermore, this automation allowed a greater degree of flexibility in the way components are held in the manufacturing process.

With the advent of Computer Aided Manufacturing (CAM), even programming CNC machines is a snap. These programs actually take the bulk of the programming process to make the operation less tedious. However, to be an effective programmer of CNC machines, you have to know what the machine you’re working on will be doing. That is why machinists are often the best people for the job.

The ease that the machines provide is hinged heavily on the quality of the machine. Low-cost CNC machines oftentimes have many functions that have to be manually activated. High-cost machines, however, are almost fully automated. The operator only has to load or unload workpieces. Once the cycle has been initiated, the operator just has to sit back and watch for any malfunctions. The stress on the operator is so low that some even complain of boredom in the middle of a cycle.

CODING

The programming language that CNC uses is called a G-Code. These codes actually position the parts and do the work. To be able to have a machine work properly, you have to input the correct variables such as axes, reference points, the machine accessories, and whatnot. Every machine has a different set of variables so you have to be careful to take note of the differences.

Aside from the G-Code, logical commands or parametric programming can be used to make the process more time-efficient. This type of programming language shortens lengthy programs with incremental passes. A loop can also be programmed thereby removing the need for coding repetitions.

Because of these features, parametric programming is more efficient than CAM. It allows users to directly and efficiently make performance adjustments. It also allows extensions to the functionality of the machine it is running on.

And that makes CNC.

If you carve your name on a wood using a very sophisticated font, you’re lucky if you’ll finish your first name in 24 hours perfectly. Years ago, wood crafting and metal crafting are very expensive massive- labor industries because every aspect of the manufacturing is done by hand. There was minimal machine intervention but the designs were still as intricate.

Today, with the help of technology, wood carving, metal molding, cutting and even finishing can be done simultaneously with minimal hands involved. In fact, a company is deemed unproductive if it mass produces products every day BY HAND.

CNC (Computer Numerical Control) machines are in demand in industries where hands are better off pushing buttons than doing actual labor. Businessmen are raving about this wonder-machine because it is accurate, speedy and flexible.

The CNC machine is actually a factory of its own. There are different parts that have specific functions. Let’s get to know the “factory workers”.

THE VICE

The Vice is what holds the material which is to be cut or molded. It is important that the vice must be tight; so the material will be held securely. When the CNC machine starts to operate, the material will dash out of the vice if it is not secured. The vice usually works like a clamp that needs to hold the material not just securely but also in the right position.

THE GUARD

The Guard—just like any other guard—works like a “protection” to the person operating the CNC machine. Once the CNC starts working, scraps of the material can “shoot off” at high speed. This is very risky for the operator if a piece hits him/her. The guard completely covers all the hazardous sides of the CNC machine.

THE CHUCK

The chuck holds the cutting tool. Sophisticated designs require maximum chuck precision so the actual design can be realized.

THE MOTOR

The motor rotates the chuck at very high speed. It is hidden and protected inside the machine. You have to take care of this part very carefully. Nowadays, cooling and lubrication is automated in most CNC machines. Usually, if this part doesn’t function well, it is the most difficult to treat. It is advised to have a CNC technician handy all the time.

THE LATHE BED

Like the sea bed, this is the sturdy base of the CNC machine. It is connected to the headstock and aids the carriage and tailstock to be parallel with the spindle’s axis. It is securely bolted so it remains unshaken by the vibration of the machine when it starts operating.

THE CUTTING TOOL/ CUTTER

This is the where the first-level shaping occurs. The cutter is usually made from high quality steel so as to cut the specific material fed to the CNC machine.

As a businessman, it is important that you get to know your employees, bond with them and earn their respect without scaring them. When you have CNC machines working for you, it is equally important that you understand them well. Do not be fooled by the CNC machine salesmen who court your interest because they are usually just after your purchase.

You have to master what comprises these machines, what makes them dysfunctional and most of all, what makes them stay in your company. Just don’t start talking to them. That would be really, really, dysfunctional.

Understanding the Computer Numerical Control Machine as well as learning the method of programming these machines is not enough to maximize the capability of these devices. Even if you are proficient on those two stated above, proper understanding of the step by step procedures is still important.

In this article we would talk about the step by step procedures of programming Computer Numerical Control Machines which is recommended by the most experienced CNC Machine Operators and progammers.

Step by Step procedures in planning of a CNC program

Whenever we try to program a Computer Numerical Control Machine the first thing that the Machine operator should consider is the blueprint of the part we are trying to manufacture. Proper understanding and reading of a blueprint is a basic and the most important skill in the manufacturing Industry that engineers, managers, CNC machine operators as well as CNC programmers should know about.

Proper understanding of these blueprints should help the CNC machine operator as well as the programmer to use the appropriate CNC machine to be used.

The second step on the proper programming of a Computer Numerical Control Machine is by selecting the appropriate type of Machine that will be used. This is where the proper understanding of each machine type comes into play. Knowing the type of design, specifications as well as features of a machine will help you on choosing the appropriate one.

The third step would be the analysis of the operations or the setup sheet. The setup sheet is used to describe the necessary processes needed to create the parts on a CNC machine. The setup sheet includes the proper machine sequence and also the tools and cutting data to be used. Specifications written on the setup sheet aids the programmer on the proper algorithm needed by the Computer Numerical Control Machine.

The fourth step on the step by step requirements would be the proper selection of the tools required to create the parts. This step is important on the industry manufacturing practices, basically the tools to be chosen is based on the common sense and Good CNC operators and programmers should be aware of them. Usually there is a certain checklist on this step, the most important point of this checklist would be knowing the material to be machined as well as its characteristics.

Fifth step would be the calculation of the cutting data. Proper calculation is one of the important steps in the planning process. This is where the spindle speed, federate value, cutting speed and the depth of cut is calculated to fit to the specifications in the blueprint.

Sixth step would be the actual programming process, this is also the step where the proper Units are inserted into the programming algorithm of the Computer Numerical Control Machine. This is where we incorporate all the codes that are needed to run the whole CNC machines in the CAD software.

Programming Considerations

In order for other programmers to analyze and append your algorithm, it is important to have certain programming considerations. These program considerations were suggested by experienced Computer Numerical Control Machine Programmers and Operators.

First it is important that you develop a programming technique that will be readily understood by other developers, with a good programming technique programs could easily be appended if there are any errors.

Second, it is also important to proofread all programs for typographical errors before being executed in the CAM software, this is to ensure that the CNC machine would operate its desired operation. And most important of all is to keep your programs as simple as possible in order for the machine to process the instructions faster.

A CNC machine cannot function without a program. And a program cannot make its way to the machine without an effective data transfer system. So, what are the methods of data transfer and how effective are they in conveying data from one point to the next?

Punched tape

The first data transfer method is the punched tape. It consists of a long strip of paper with holes punched in it to store data. The holes represent a set of data that tells the machine how to move and what to do.

This method has proven to be very versatile and very useful. It has proven to withstand the test of time as numerous magnetic storage devices have deteriorated over time even to the extent of being unreadable while punched tape has been shown to be fine decades and perhaps even centuries later. Repair is also not a problem as specially designed splices can put two end together virtually unchanged. Furthermore, punched tape can be visually decoded should the need arise. This means that human accessibility is also not a problem.

Floppy Disk

While punched tape is quite a long roll of paper, a floppy disk is a small magnetic storage device that is more space efficient than punched tape. It can also be used to store simple programs.

Floppy disks virtually revolutionized the way data could be stored and transferred from one point to another. It allowed users to store and transfer data faster than punched tape allowed. Furthermore, the data within a floppy could be easily edited at any point as long as you have the proper program to read it. However, this method has proven to be quite problematic in the long run as floppies have a tendency to degrade alarmingly fast. A floppy could be unreadable after only 3 years.

RS232

This method is actually a set of standards for serial binary signals that connects between computers, terminals, and modems. This is a fast and efficient way to transfer data.

This cable connects a CNC machine to a computer that has floppy disk support thus eliminating the need for punched tape. This allows the operator to input data remotely and even while accomplishing other tasks. However, it need to be used in conjunction with an effective data storage device so as to have backups in case of emergencies.

Networks

Networks are a set of computers that are linked together to make data sharing easier. In an industrial scenario, networks allow a number of different users to individually create a program for the machine to run on.

This method allows multiple users to access and transfer data remotely. This allows for a faster and more efficient check-and-balance system for the programmer and the data verifier. Furthermore, different parts of the program can be completed by different programmers and then compiled by one user. This makes program creation a fast and easy process.

Manual Data Input (MDI)

MDI allows users to input commands directly into the CNC machine’s memory. This may seem to be an effective way of telling the machine what to do but it actually has a lot of drawbacks to it.

Despite it being the fastest way of telling the machine what to do, it is also a very risky and tedious operation as it requires the use of the machine’s terminal. Furthermore, the construction of a program is not as fast as opposed to the network method. It only allows one user to access the machine thus making it a long and drawn-out process.

Another disadvantage that comes with MDI is that it limits the operator to only one task at a time. However, MDI allows the most control over the machine compared to other methods.

When a program is completed and sent to the Computer Numerical Control Machine, the programming process is over. All calculations were made and the algorithm fully written. But the question is the programmer’s job really finished? When is the programmer’s responsibility really over? And how can we evaluate the type of program that the Computer Numerical Control Machine programmer did?

The fairest and reasonable answer to those questions would basically when a part has been machined under the most optimized working conditions. Therefore the Programmer’s responsibility does not end after he or she finishes the program. We could say that the program at this stage is still very much in the development process, because most of the programming considerations were based on certain assumptions and there are a lot of external factors that may affect the outcome of the product.

Every Computer Numerical Control programmer should have an effort to be in the touch with the actual production. In the field of software development, Constant communication with your colleagues as well as actual machine operators of the CNC will help you to improve your own program. Because most of the time the CNC machine operators are a good source of constructive ideas, improvements and suggestions.

A good CNC programmer should talk, ask questions to them and most importantly listen to what they have to say. Programmers who never put their foot in the actual machining process and think they are always right are all on the wrong track. Exchanging ideas with CNC machine operators, asking questions and seeking answers is the only way to be fully aware of what is going on in the machine.

Whenever you start a Computer Numerical Control Program the first time it is important to check its Program Integrity. A new and unproved program is a potential source of problems. During Manual Programming in CNC, mistakes are more common than when the program is made in a CAM program.

A good way to look at a new program is through the machine operator’s perspective. Experienced Machine Operators take a direct approach when running a program for the first time. That means that they wont take any chances of mistakes with the actual running of a program therefore a good programmer must take note of any comments that the Machine operator will say about the program.

What does an experienced Machine Operator look for in a new part of a program? Most of the Machine operators would say that the first and most important thing to be checked on a Computer Numerical Control Program is its consistency. Therefore a machine operator looks at how a CNC programmer does its own programming, is the way you create your own algorithms the same as the other ones. Machine Operators take note with this kind of Information.

Upgrading your CNC Program

Whenever you upgrade your own program, it means that you are strengthening or enriching it, therefore making it better than it was before. Upgrading would be based on this standard, It is to decrease the production cost without compromising the quality of the part being manufactured or the safety of the Computer Numerical Control Machine Operator.

One of the Most Common forms of Program Optimization is doing some minor changes to the spindle as well as the feed rates of the machines. This process is called cycle time optimization, slightly increasing the spindle speed and feed rates of these machines will decrease the time it takes to finish the part.

And when we compare it to mass production, saving one second for each part in a batch of 3600 pieces would mean an hour saved. Efficiency in the rate of production is a very important aspect in Mass Production.

The normal businessman’s mind is always geared towards profit, profit, profit. No matter how much the company spends, at the end of the day, the revenues should exceed the expenses (including tax). Although innovation is a major requirement to a business’ growth, many small-time businesses just lie back in comfort. They think that as long as they’re earning and they have a steady market, it’s all right.

This holds true for businessmen who are contented with being small-time (though it’s hard to find one). However, for businesses that are aggressive towards getting ahead, acquiring a CNC machine seems to top their list of priorities.

CNC stands for Computer Numerical Control. A CNC machine is a computer “director” which is composed of machine tools that read a specific set of instructions (in G-code) and is able to “direct” certain manufacturing tasks repetitively. The top industries that use the CNC technology are the Metal and Woodworking industries.

If you are a regular member of a techie forum for entrepreneurs, CNC may be showered with praises because of its performance. Most businessmen also swear by saving a lot of money and time when they started employing CNC technology in their production processes. However, if you are still considering CNC at the expense of the jobs of your employees, it is best that you prefer CNC at two levels: the logical level and the emotional level.

LOGIC-WISE

CNC machines do specific instructions. They will never assume anything, nor rebel against the program loaded to them. Imagine the security of knowing that you will “reap” exactly what you “sowed”. Let’s say, something goes wrong during the process. Assuming the machine is in perfect condition, you CANNOT put the blame on it because it just performed what you told it to do so.

Secondly, there is the blanket of consistency. It provides a certain level of safety and ease to the head supervisor. If you have overseen the operations today, most likely, it will be exactly the same tomorrow. The feeling of knowing what to expect is always a good thing, especially when there’s money involved.

Lastly, there’s speed. CNC machines do not stop to think. After you do the thinking, they do the power-jobs that they need to do. It’s that simple. There is a minimized set-up time and back-job time pocket.

What you will find a flaw about CNC though, is that logic-wise, CNC machines cannot think of better ways to perform a task (IF there is a better way). A CNC machine is purely mechanical; when it was sold to you; the salesmen never mentioned the word “creative” or “innovative”. I hope you did not miss that.

EMOTION-WISE

CNC machines are also assets of the company. When assets like this are purchased, there is little or no emotional investment that goes with it. You won’t even train it! It is expected to do certain tasks and that’s saving you a lot of time from all the explaining, demonstration and reminding.

Also, when a CNC machine is performing its task, it is void of any emotion. So no matter how hot the weather is, or how noisy the workplace is, the CNC machine will do its job just like any other day. It is different as compared to people – who have the tendency to space-out when doing very mechanical and tedious jobs.

Although the CNC may want to, it also cannot complain. That’s really convenient. What you will need to note now is your electric bill. Beware, for when getting CNC machines, it may betray you in the form of lofty bills. All the emotions you’ve saved might just be unleashed.

Being a CNC operator may seem a little too easy but take a look at the requirements from companies and you’ll think twice about the difficulty level of being a CNC operator.

Being a CNC operator takes a lot more than just being able to handle long hours of staring at the monitor or creating an input stack for the programs. What it means is that you have to have outstanding programming capabilities and at least basic machining knowledge.

Job Requirements

A CNC operator has to be knowledgeable about blueprint reading. This is because, basic design concepts and construction is hinged heavily on blueprints. Furthermore, the components that are being manufactured by companies that have CNC machines are based on blueprints of a whole structure. Therefore, if you do not know how to read blueprints, you won’t know what to program the machine to do.

Another thing that a CNC operator has to have is familiarization with machine operations. If the operator does not know which machine tools are for which job, or how fast the machine can work, or what the rate of feed is for the machine, or even the depth of the cut needed for the operation, then you wouldn’t be productive and the operation would be a failure.

The most obvious thing that an operator would have to know would be the general operating characteristics of the machine. He/she would have to know what the machine runs on—tape, network data input, or floppy. Furthermore, proper data input procedures have to be observed to lower the error ratio. A faulty data input procedure could cause the entire cycle to collapse therefore lowering the level of efficiency.

Working with CNC machines means that you will also be dealing with a lot of computer work. This means that you have to be familiar with basic computer operations. In addition to that, you will have to know how to interpret data in the program output stack.

The company’s requirements and the benefits.

some companies require a lot more than what is written above. Oftentimes, they require applicants to be familiar with the system that they use. Other times, they want the applicants to have no less than five years of experience working in a factory or at least working with a CNC machine. Also, some companies require applicants to undertake a specific training program to ensure the employers that the material they are getting is worth the money they will be shelling out.

However, the benefits that can be reaped is quite solid. Salaries and insurances are often negotiable. Working hours are also a snap! All you would have to do is initiate the cycle and then sit back and occasionally check for glitches. Furthermore, these companies often takes care of their operators as there is always a shortage of skilled enough people to take hold of the position.

So, what does it take to be a CNC operator? To synthesize the requirements, you have to be amazingly determined to pass the requirements of the company you are applying for. And then, you have to be able to quickly restructure the program in case of any glitch that the computer might encounter during the process.

The benefits are solid, but passing the requirements is like surviving the gauntlet. Think about this career.

Are you good with computers and looking for a job? Well then, consider being a CNC machine operator. It’s usually easy, full-time and the name isn’t intimidating, right?

If you think that being a Computer Numerical Control (CNC) machine operator may be a bit out of your reach, think again. You don’t have to be a math wizard or a programming genius to get that position. But don’t jump in just yet! There are a few things that you have to know (and consider! ) before applying for the job.

The first thing that you have to understand is the abbreviation CNC. According to an online encyclopedia, CNC stands for Computer Numerical Control, and refers specifically to a computer “controller” that reads G-code instructions and drives a machine tool, a powered mechanical device typically used to fabricate components by the selective removal of material. CNC does numerically directed interpolation of a cutting tool in the work envelope of a machine. The operating parameters of the CNC can be altered via a software load program.

THE PROS

The good thing about being in this job is that the workload is actually light. Operators even complain of boredom because the cycles of CNC machines are all automated. All they have to do is initiate the sequence, sit back, watch for malfunctions, adjust the performance of each machine, and turn them off. If your boss is kind enough to let you use an MP3 player while working, then you sure are lucky.

Another good thing about this job is that job openings for this position will always rise. Technology is moving forward. CNC machining will certainly lead the demand because in CNC, a group of machines can be controlled at the same time. That is exactly what big-time companies want, right? To reduced manual overseeing and just leave it to the machines.

Advantage in this job arena is easy too. Statistics show that you will need only a high school diploma and (more importantly) an experience in CNC operations to gain an edge.

THE CONS

The thing is, when you’re in this line of work, it is repetitive. One gets bored after doing the same mechanical thing over and over again. As time withers, you will reach a point where you will breathlessly wait for the next paycheck and not actually care about the job. It’s emotionally exhausting. Furthermore, programming and operating these machines can be tedious. So, add that up to boredom and you get disproductivity.

Another thing that you should think about is the work environment. You’re going to be working in a factory. And factories are located away from town. If you’re not comfortable with being away from the hustle and bustle of the city, this might not be for you.

It can get pretty dangerous. Reports show that although most CNC operators work in a well-lit and smoothly ventilated environment, the high-power machinery poses dangers for them in the form of flying particles of metal and plastic. Also, though most modern machines produce less noise, ear plugs are still recommended by experts.

Lastly, this may not sound like a biggie, but most CNC operators are on their feet all day. They can only sit when the programs are being loaded into the computer. It’s pretty comforting that they receive salaries waaaay bigger than those salesladies.

CNC has different applications depending on the machines that operate on it. So if you’re a budding operator, you should know the most common machines that can operate on CNC.

Milling

Milling machines are common CNC machines. These devices are used in the shaping of metal and other solid materials. It is basically a rotating cutter and a table. Milling machines are capable of complex toolpaths as the cutter is not limited to a sideways movement but allows for an “in and out” motion. This movement is precisely controlled by moving the table and the cutter relative to each other. Cutting fluid is then pumped in to lubricate and cool the cut and to remove any swarth that is generated by the cut.

Lathes

Lathes are machines that perform different operations such as sanding, cutting, knurling, deformation, or even drilling. These machines work by spinning various solid objects and then using tools that are symmetric to the axis of rotation. A lathe machine has a single tool in which the workpiece is worked against the tool. The tool is then worked alongside or into the workpiece in order to generate the feed.

Lathes can be used for different operations.

Machining Centers

These are more complex CNC machines that combine milling and turning. As milling was described earlier, turning will be the focus of this section.

Turning is the process by which a central lathe is used in conjunction with the rotation of the material to be turned. The cutting tool is then moved along the two axes of motions to produce accurate dimensions.

Combining turning and milling can produce extremely precise components. And that is what these machines are used for. However, due to the complexity of these machines, operators have to be specialists in order to be able to operate with maximum efficiency.

Electrical discharge machine

An electrical discharge machine (EDM) creates cavities in metals by emitting electric sparks. This process requires an electrode, coolant, a power source, and a tank. The cycle is accomplished by connecting the workpiece to one side of the power supply and then placing it in the tank. An electrode (made in the shape of the cavity required) is then connected to the other side of the power supply.

The tanks is then filled with coolant and the electrode is lowered until a spark jumps between the work and the electrode. As the coolant is a dielectric substance (resists electric currents), it requires a smaller difference in distance in order for a spark to jump through. This means that when the spark appears, the dielectric property has been overcome. The spark then dislodges material thereby creating a cavity in the shape of the electrode.

CNC systems

CNC systems are complex machines that transfer and store data regarding the operation mechanism of the machines. Motion programs include point to point control, straight cut control, and contouring control.

Point to point control means the control of the tools from one point to another in the coordinate plane. This method of control is commonly used in drilling and boring operations.

Straight cut control is the method by which a tool is moved in all axes of the machine. The tool also has the ability to move in a 45 degree angle.

Contouring control is the means to create a toolpath. It moves the tools by interpolating points or coordinates that make up the path for the tool to follow.