How Slot Machines Work
Slot machines were first deployed in casinos as a diversion for casual gamblers. Unlike conventional table games (such as blackjack or craps), slot machines do not require any prior gambling experience, and anybody may participate with a little water.
This concept proved to be a colossal success, with slot machines eventually being the most popular and profitable game in town, accounting for more than 60% of all yearly gaming earnings in the United States.
Machine technology has evolved significantly over time, and Computer-controlled machines have nearly replaced traditional mechanical designs. However, the game has not changed. The player rotates a number of reels (usually three) with pictures printed on them by pulling a handle.
Which photos line up with the pay line, a line in the centre of the viewing window, determines whether you win or lose. You win if each reel displays the same winning picture along the pay line (certain single images are sometimes winners as well). The amount you win (payout) is determined by which images appear along the pay line.
The traditional slot machine architecture relies on a complex system of gears and levers. The metal shaft that supports the reels is the key component, and this shaft is linked to a movement-inducing handle mechanism. The spinning reels are brought to a halt by a braking mechanism, and sensors convey the location of the reels to the payment system. A coin detector detects the presence of a coin and releases a brake, allowing the handle to move.
There are a plethora of ways to organize these components, and manufacturers have attempted many of them over the years, so we’ll concentrate on one sample design. Three reels are arranged on a central shaft in the basic configuration. The center shaft likewise supports three notched discs linked to the three reels. A kicker, a metal device with three paddles, is supported by a second shaft underneath the center shaft. The kicker paddles are positioned such that they may press against the three discs’ notches. The second shaft supports a set of linked stoppers, teeth that lock into the notches on the discs.
Both the kicker and the stoppers are attached to springs that keep them in the ready position. The kicker is secured behind the discs, while the stoppers are pressed against the discs to secure them.
These components do a lot of work when you pull the handle on a slot machine. In the following part, we’ll look at exactly what happens.
Pulling the Handle
When a person pulls the handle on a slot machine, a series of events occur. Here’s how it works:
The handle spins a hook mechanism that snags the kicker and pulls it forward (toward the player).
A catch on the kicker’s opposite end snags and pivots a control cam piece forward. A sequence of gears attached to the control cam spin as a result of this. The control cam is returned to its original position by a spring, but the gear assembly slows it down significantly — the gears operate as a mechanical delay.
A spring-mounted cam plate extending across the rear of the machine is released when the control cam is turned forward.
The stoppers are also pulled away from the notched discs by the control cam. The stoppers are pushed against various catches on the cam plate while the kicker continues to move. These keep the discs and reels spinning freely by holding the stoppers in place.
The kicker paddles temporarily push the discs forward as the handle continues to move the kicker. The bottom of the hook mechanism slides up against a slanted surface after the handle is fully retracted and the kicker has passed the discs. The slant forces the hook to tilt forward, releasing the kicker.
The kicker spring rapidly pulls the kicker backward. The kicker paddles collide with the notches on the discs, swiftly spinning the reels.
The control cam is slowly returning to its original position as all of this is going on. The cam plate is pushed back when it returns, releasing the stoppers. The many catches that retain the various stoppers are positioned such that the cam plate releases the stoppers one by one. Each stopper springs forward and latches into a notch, firmly anchoring the reel.
This is how it appears from the player’s perspective. The player pulls the handle. A clunk sounds, and the three reels begin to spin. The three reels then abruptly halt one by one, followed by the payment (if necessary).
The “one at a time” aspect adds to the anticipation. If the first reel stops on the jackpot symbol, you must then wait for the second and third reels to stop to determine if it is a jackpot. The player wins if all three show the correct symbol.
Electrical machines based on the same principles as traditional mechanical slot machines eventually evolved. The reels in an electrical machine are spun by motors, and the stoppers are usually operated by solenoids, but the game is essentially the same. Electrical machines feature more advanced money-handling technologies, similar to those seen in vending machines, as well as more flashy light and sound displays.
After the reels have stopped spinning in both types of systems, the slot machine must determine whether the player has won or lost. We’ll look at several techniques for making this judgment in the next section.
In slot machines, there are hundreds of various payment schemes. One of the simplest systems identifies a jackpot by detecting the depth of notches in the discs that drive the reels. We’ll look at this type of payout system in a basic slot machine for simplicity’s sake. There is just one winning combination of photos, and the machine only accepts one type of coin.
A coin falls into a clear casing when it is inserted into this machine. As seen in the diagram, the bottom of the casing has a moveable shutter that is attached to a metal connection. The connection normally keeps the shutter closed. However, when the machine hits the jackpot, the third stopper moves the linkage up, opening the shutter and allowing the coins to tumble out.
Each of the three discs features notches for each of the reel’s stop positions. The jackpot stop has a deeper notch than the other stops. As a result, the first stopper slides farther to the left than any other stopper when the first reel falls on the jackpot stop. If the second reel likewise stops on the jackpot, the second stopper also advances to the left. The third reel and stopper are the same.
The second stopper will not travel into the notch if just the second reel stops on the jackpot. A catch on the first stopper prevents the second stopper from sliding beyond it.
The third stopper is held back by the second stopper, which features a catch. The first and second reels would have to land on the jackpot picture for the third stopper to lock all the way into the jackpot notch. The shutter then opens, dumping all of the coins that have been played since the last jackpot.
To pay out partially on specific picture combinations and totally on the jackpot combination, slot machines usually feature more complicated variants of this concept.
The discs are joined to a series of metal contacts in another popular technique used in some electrical equipment. When the reels come to a halt, one of the contacts engages a circuit board-connected stationary contact. Each stop on each reel will close a separate switch in the electrical system in this manner. The payment methods is operated by configuring the machine’s electrical circuit with certain combinations of closed switches (jackpot winners).
To detect the location, a more sophisticated system employs photoelectric cells (also known as photodiodes), which are devices that create a current when exposed to light.
A number of holes are bored all around the outside edges of the revolving discs in this arrangement. There is a photodiode on one side of the disc, and on the other side, there is a light source. The light shines through the holes on the photodiode as the disc rotates. The photodiode generates a similar pattern of pulses of electricity due to the pattern of holes in the disc. An electrical circuit can calculate the location of the reel based on this pattern.
Instead of gears, newer slot machines employ computers. Next, we’ll take a look at those.
Computerized Slot Machines
Modern slot machines are meant to resemble older mechanical counterparts in appearance and feel, but they operate on an entirely different concept. Instead of the motion of the reels, a central computer inside the machine controls the outcome of each draw.
To spin each reel and halt it at the appropriate position, the computer employs step motors. Instead of the fluctuating electrical current that powers a regular electric motor, step motors are powered by brief digital pulses of electricity controlled by the computer.
The games are not pre-programmed to pay out at a specific moment, even if the computer directs the reels where to stop. The computer’s random number generator guarantees that each draw has an equal chance of winning the jackpot.
When the slot machine is turned on, the random number generator spits out entire numbers hundreds of times per second (usually between 1 and several billion). The computer captures the next few digits from the random number generator as soon as you pull the arm back (or click the button). The numbers are then sent into simple software, determining where the reels should stop.
In a standard three-reel machine, the entire procedure looks like this.
When you pull the handle, the computer records the random number generator’s following three digits. The first number determines the first reel’s position, the second number determines the second reel’s position, and the third number determines the third reel’s position.
Let’s imagine the first number in this example is 123,456,789.
The computer divides the first random number by a predetermined value to determine the location of the first reel. Slot machines are usually divided by 32, 64, 128, 256, or 512, and we’ll assume the computer divides by 64 in this case.
The remainder of the quotient is recorded when the computer divides the random integer by the predetermined value. 64 goes into 123,456,789, a total of 1,929,012 times, with a remainder of 21 in our case.
Because the residual cannot be more than 64 or smaller than 0, this computation can only have 64 potential outcomes. The 64 potential values function as virtual reel stops.
Each of the virtual reel’s 64 stops corresponds to one of the actual reel’s 22 stops. For each value on the virtual reel, the computer checks a table that informs it how far to move the actual reel. Due to a large number of virtual stops compared to actual stops, some genuine stops will be linked to many virtual stops.
Slot machines have become far more versatile because of computer technology. Instead of slipping coins in for each draw, gamers may now gamble money directly from a credit account. Players and casinos can both keep track of their gains and losses more simply. In current machines, the procedure is also simplified; instead of pulling the handle, players may simply click a button to play a game.
For machine producers, one of the key advantages of the computer system is that they can easily adjust how often the machine pays out (how loose or tight it is). The computer software may be modified to modify the slot machine’s odds of striking the jackpot in the next section.
What are the Odds?
The chances of hitting a certain symbol or combination of symbols in a contemporary slot machine are determined by how the virtual reel is set up. As we saw in the last section, each physical stop on the reel might correspond to several virtual stops. How many virtual stops correspond to the actual stop determines the probabilities of hitting a specific picture on the actual reel.
Each reel’s top jackpot stop (the one with the highest-paying jackpot picture) corresponds to only one virtual stop in a standard weighted slot machine. This implies that hitting the jackpot picture on one reel has a 1 in 64 probability of happening. The odds of landing the jackpot picture on all three reels are 1 in 643, or 262,144. The simulated reel on machines with a higher jackpot may have many more stops, significantly reducing your chances of winning the jackpot.
The lost blank stops above and below the jackpot picture may correlate to more virtual stops than other images. As a result, the blank stops are most likely to be hit exactly near the winning stop. This gives the sense that players “barely missed” the jackpot, encouraging them to keep wagering despite the fact that the distance between the real stops is insignificant.
The machine’s program is carefully planned and tested to reach a specific payback percentage. The payback percentage is the amount of money that is returned to the player after it has been invested. For example, if the payback ratio is 90%, the casino will take around 10% of all money placed into the slot machine and give the other 90% away. The casino wins over time with any payback percentage below 100 (which is all of them).
In most gaming jurisdictions, payback percentages must exceed a particular threshold (usually somewhere around 75 per cent). Most casino machines have a substantially greater return percentage than the minimum, frequently in the 90- to 97-per cent range. Casinos do not want their machines to be significantly tighter than those of their rivals, or gamblers will go elsewhere.
The odds for a certain slot machine are programmed into the machine’s computer chip. The casino cannot usually modify the odds on a machine without replacing this chip. The casino cannot suddenly “tighten up” a machine, contrary to widespread belief.
Machines, too, do not loosen up on their own. That is, the longer you play, the less likely they are to pay. Because the computer generates fresh random numbers every time you pull the handle, you have the same chance of winning the jackpot every time you do. At least under the normal system, the concept that a machine might be “ready to pay” is entirely in the player’s brain.
When it comes to slot machines at a casino, there are dozens of possibilities. For example, different machines have different numbers of reels, and many have several pay lines.
Most machines with numerous pay lines allow players to select the number of lines they want to play. Only the one line traveling straight across the reels counts for the minimum bet. With extra money, the player can play the additional horizontal lines above and below the primary pay line, as well as the diagonal lines that run across the reels.
Players will normally be eligible for the maximum jackpot only if they place the maximum wager on machines with several bet possibilities, whether or not they have multiple pay lines. As a result, gambling experts advise players to always stake the maximum.
Modern slot machines have various distinct payment systems. The payoff amount on a conventional flat top or straight slot machine is constant. A progressive machine’s jackpot payment, on the other hand, grows continuously as players put more money into it until someone wins it all and the jackpot is reset to a beginning amount. In a shared progressive arrangement, multiple computers are joined together in one computer system. The money placed into each machine goes toward the grand prize. Machines from many casinos throughout a city or even a state are hooked together in some massive progressive games.
Some variances in slot machines are purely ornamental. Video slots work in the same way as ordinary machines, except instead of revolving reels, they contain a video picture. When these games originally came out, players were skeptical; the games appeared to be rigged without the spinning reels. Even though the reels and handles on contemporary machines have no bearing on the game’s result, they are generally included to give players the impression of control.
These are just a handful of the most popular slot game types today. Game developers continue to create new types of machines with unique twists on traditional games. Many of these versions are based on certain themes. Slot games themed on television shows, poker, craps, and horse racing, to mention a few, are now available.