Automatic card shuffler

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Executive Summary:

The primary purpose of the Automatic Card shuffler originally was to take away the burden of one shuffling cards in a card game. What usually takes place in a card game is that players would take turns shuffling the deck of cards in order to rearrange the previous order that the cards were in. This action was to ensure that each player recieves an even hand when the cards are dealt out evenly. Now assuming that we live in an ideal world, the cards would be shuffled evenly so that neither player wouldn't have an unfair advantage. In reality the chances of the cards being shuffled evenly on a consistent basis are very slim. One factor could be the simple fact that some people cannot shuffler as good as others. Furthermore some people cannot not shuffle at all. As a result, there isn't really a pattern that the deck of cards follow after a person shuffles them due to human error. This human error is the result of poorly shuffled cards because of a lacking in the ability to shuffle cards effeciently. The deck might still have particular cards together prior to the shuffle as a result of human error. The Automatic Card shuffler serves if not to completely eliminate, then reduce this error as much as possible.

The basic functionality of the automatic card shuffler is to take one or two decks and alternately shuffle them into a central holding compartment. It is powered by two “C” batteries which are connected in series to the motors and gear trains. The on/off switch consists of a spring loaded button that depresses a curved piece of sheet metal, which in turn completes the circuit. The motor and gear train mechanism rotate a rubber wheel which pulls cards alternately from both sides on top of the shuffler. After all the cards have been shuffled, the user can then slid out the plastic holder and reinsert the cards to the top and reshuffle if desired.

The assembly of the product involves various manufacturing processes. The gears, which transfer rotational motion from the motor to the rubber wheels on top, were made through an injection molding process. The outer shell/casing, which holds the cards during pre/post shuffling were likely also made through an injection molding process. Afterwards, the individual pieces were probably glued and finally a CNC mill cut out the rectangular holes throughout the body. The plastic viewing screen on top was most likely made through injection molding while the attached metal sides were probably made by stamping. Overall, the manufacturing aspect of the shuffler has been optimized fairly well and we feel there isn't much to be improved upon with regards to cutting costs or simplifying the manufacturing process.

In terms of product flaws, we noticed that some could easily be modified and corrected. By doing marketing research, analyzing design and survey, we have gotten alot ideas for putting new design along with more useful features on the existing product. Our goal here is to make the shuffler more functionable and convenience, make it become one of good friends whenever there is a card game. We have determined that consumers of this product generally want something that can help not only the shuffling aspect of cards, but will serve other functions to all aspects of improving the quality of playing cards games. One recommedation we have is to include holding slots for other decks of cards or dice. Another idea is to include a score tracker either electronic or physical. Things like these can be implemented without too much increase in cost or manufacturing and would enhance the performance of the shuffler.

We have come up with a key areas of improvement that we feel should be focused upon with respect to the design of the shuffler. In our research we received a lot of complaints that the shuffler was very noisy when operated and we think a simple solution to this would be to include some kind of dampening material to the product where the cards hit the side walls when they get shuffled to muffle the noise. Another area for improvement is the output tray slot. We noticed that it took more effor than necessary to remove the cards after they have been shuffled since the output slot is recessed in the shuffler as well as behind the operating button. Moving the operating button and exposing the output tray more would solve this problem. Another key area that we feel which could use improvement is the randomness of the shuffle. We have done research that shows that the card shuffler shuffles very consistantly which could result in an easy prediction of the outcome of shuffling. We have proposed our top designs below in the report to address these issues.

Customer Needs/Requirements

There are certain customer needs which the automatic card shuffler should perform: speed of shuffling, battery life, simplicity of use, quality when shuffling, adequate level of mixing, features, price and durability. It has to be carefully designed for quality purposes in order to reach high levels of performance while maintaining lower manufacturing costs and time consumption. Cards produced through automatic shuffling machines generate random unbiased cards that generate no unfair advantage to any user, i.e. either gambler or casino, allowing for less speculation of unfairness by players or accusations of cheating by the casino.

Random shuffling machines are also beneficial for personal usage in cases of people who do not know how to shuffle, shuffle too slowly, inadequately, or are merely too lazy to do so. The shuffler needs to be easy to use and the procedure of working with the product must undoubtedly require less effort than doing so by hand. Also, it should also shuffle/process faster than the average processing time required by doing the same procedure manually with human hands. For the senior users, it would help to save the time of reading and learning the user’s manual, to reduce the cost of wasted time shuffling, to enjoy their card game, which further creates an emphasis on easiness to use.

When people make a decision regarding purchase, pricing of the product will become an issue. Since the product costs an estimated $10, we look for the product with lower cost and higher quality, specifically higher durability. The durability can be divided into two categories: mechanical and electrical. The majority of shufflers currently available on the market are made by plastic with vulnerable components; the mechanical parts are what cause the majority of machine failures, requiring a need for greater durability.

For continuous use over the maximum amount of time, the design of the automatic card shuffler must focus on how to best utilize battery power, and make the batteries less consumable. Possible substitutes to elevate concerns over battery life can be using an additional smaller battery, or human-hand power. All are extremely viable and cost effective solutions. In addition, we will need the product to be easy to carry and store. The smaller size, lighter weight and feasible structure of product will make it more accessible for users.

The automatic card shuffler mimics human actions, cutting the deck and interlacing cards to perform riffle shuffles. Typically, an automatic card shuffler pulls cards one by one from the bottom or top of a deck and slides each card into another. Most of the card games require cards to be shuffled randomly which means the shuffler has to perform great randomness of final product. “Is it fair to use a card shuffler?” This has recently become a really popular research topic by people since more and more people have become recreational card players, especially with the growing popularity in media circuits of card games such as poker. If the cards are not properly shuffled and their distribution is not truly random, the advantage could be even greater.

List of Customer Needs and Product Requirements

List Customer Needs Product Requirements
1 Easy to Use Overall Design
2 Save Time Speed of Processing
3 Randomness Shuffling Design
4 Easy to Carry/store Light Weight/Smaller Size/Good Structure
5 Durability Mechanical Design/Battery Life
6 Features/Functions More Accessories
7 Price Lower Cost to Manufacture
8 Quality of Shuffling Make Less Noise

How the System Functions

Inner Component Diagram

  • 1 - Metal Tabs (located under "shuffle" push button)
  • 2 - Battery Compartment
  • 3 - DC Motors
  • 4 - Rubber Gripper
  • 5 - Various Spur Gears
  • 6 - Sector Gear
  • 7 - Metal Shafts for Gear Train


The purpose of the automatic card shuffler is to shuffle one or two decks of playing cards. It is used to simplify the overall shuffling process, and to take out the human error aspect of shuffling. People who are playing a card game such as poker or blackjack can use the automatic card shuffler to substitute for hand shuffling. The shuffler is meant to speed up the shuffling process and provide the ability to shuffle cards for those who can't shuffle. The device also eliminates the possibility of someone cheating while shuffling or shuffling with error. The automatic card shuffler will also stack the cards into a neat pile ready to be dealt out in a game. The product will also speed up the overall gameplay as people will not have to take turns while shuffling the cards. The card shuffler also reduces wear on the cards since the shuffling process does not involve bending of the cards.


The input of the automatic card shuffler is the placement of the cards into the two card holding slots. The user then starts the device by pressing down on the trigger switch. When depressed, this switch will complete a ciruit that connects the batteries to two small motors that spin at high speed. The motors are small and produce high speed but with little torque so gears are used to gear down the speed while increasing the torque applied to the cards. The gears are connected to a wheel which draws the cards from the two card holding slots into the middle output slot. The motor will continue to run and the wheels will spin until the lever is released. The user then retreives the cards from the middle output slot to use or to repeat the shuffling process by placing the cards back into the two card holding slots.

Use and Operation

To operate the card shuffler, the user must first place two "C" batteries into the battery compartment located beneath the shuffler. This involves removing the phillips screw that secures the battery compartment cover and then placing the batteries in and replacing the cover. The card shuffler should then be placed on a flat surface so that the cards placed into the machine will fall evenly. The user can then place one or two decks of cards into the two card holding slots located on the sides of the shuffler. The user preferably should place even stacks of cards into each side of the card holding slots to ensure even shuffling. Then the removeable tray should be placed into the output slot so that the shuffled cards can be removed easily. To start the shuffling process, the user will then depress the power switch located at the front base of the device. The user should continue pressing the button until all the cards have been shuffled. When the shuffling is complete, the user can then remove the tray along with the cards. Since the tray is simply a flat piece of plastic that rests underneath the cards, the tray along with the shuffled cards can be removed without having to flip them over to reveal the bottom card. The cards can then be used or replaced into the machine again to reshuffle the cards further.

Different Use/ Use Scenarios

The automatic card shuffler can be used to shuffle cards for different reasons associated with playing card games. There are many different games which require shuffling of the cards after each round such as poker, spades, speed, or blackjack. The device will primarily be used when playing card games with groups of people such as at parties or small get togethers. Some improper use of the device could result by using cards which are non-standard size or thickness. Using it for any other use other than to shuffle cards is not consistant with the original purpose.

Product Dissection

Before we tested the card shuffler, we took it apart in order for us to see how the shuffler functions and made the following assumptions:
1. There are two gear train systems.

  • One motor is driven by batteries, which in return powers the other motor.
  • The two motors are connected to each other by two wires.

2. Each gear train has its own motor.
3. For syncronization, there are two modified gears, both of which have teeth on some portion of itself.
4. One of the modified gears has its teeth pointing down, while the other modified gear has its teeth pointing up.
5. We assumed this was important because when a person places cards on both the left and right side of the card platform, one card would be lifted up while the other would be touching the surface of the card platform.
6. The card that remains in contact with the surface of the card platform is carried by a fat gear that is driven by a motor when the user presses the shuffle button.
7. This motor is powered by two "C" batteries.
8. After this card carried into the center slot with the tray, the modified gears are now in alternate positions, and the same process is repeated for the other card on the other side of the card shuffler. <nowiki>Insert non-formatted text here</nowiki>

List of Parts

Part # Part name QTY Function
001 Small Screws 4 Holds top plastic screen in place
Small Screw
Small Screw
002 Medium Screws 3 Located on bottom of case in triangular formation, under the card tray
Medium Screw
Medium Screw
003 Large Screws 8 Located along other perimeter on botom of case, to hold case together/hold the gear train case
Large Screw
Large Screw
004 Clear Top Cover 1 Located on top of case in between card decks, provides slot for them to slide through. Also, keeps the rest of the deck in place while shuffling is in progress
Clear Top Cover
Clear Top Cover
005 Operating Button 1 Contacts metal piece beneath to complete circuit allowing both motors to operate
Operating Button
Operating Button
006 Circuit Wire 5 Setup in series and connected to the battery. Circuit completed when part 005 is pushed and held down
Circuit Wire
Circuit Wire
007 Motor 2 Initiates the power to make the gears rotate in order to shuffle the cards
008 Rubber Gripper 2 Increases the friction force to grab the cards into the tray
Rubber Gripper
Rubber Gripper
009 Spur Gear 2 Changes the direction of gear rotation and creates more torque
Spur Gear
Spur Gear
010 Offset Gear 2 Makes contact with deck of cards from underneath
Sector Gear
Sector Gear
011 Gear Case 1 Covers and protects the gear train mechanism
Gear Case
Gear Case
012 Battery Compartment 1 Transfers the electrical power into mechanical power
Battery Compartment
Battery Compartment


Manufacture Analysis - After taking apart the product it was easily seen how most of the parts were made. Also, because of the fact that it is a relatively cheap item, almost everything was injected molded. Three different sized screws were used to assemble the whole product, where many of them posed a large problem when trying to get them out. The motor was probably the only component that the maker did not manufacture. As for the shape and various cutouts, a type of CNC milling process was used.

Disassembly/Assembly Analysis - The clear top cover of the shuffler is held together by the small screws and does not need to be removed in order to access the internal mechanisms. The medium screws are located on the outer perimeter on the bottom of the case, while the large screws are also located around the perimeter and also are used to hold the gear train in place. After taking them out, which was very difficult due to their size and how they were torqued, we realized that having so many screws was unecessary since the case does not go through that much stress.

Ideas For Improvement - Noticing the large number of screws used to hold the case together we thought of two options; one of which would be to reduce the number of screws in total and the other would be a snap type mechanism, elimnating the screws. Both of these would reduce manufacturing cost. The compartment that holds the cards after they are shuffled is also badly placed. It was very difficult for a normal sized hand to reach in and pull the cards. Even after trying to slide the cards out, they were being blocked by the spring loaded operating button. Moving the button to either the left of right side of the case and having the compartment slightly inclined would greatly help in accessing the cards. In turn this would also help in terms of shuffling speed so as to create minimal downtime/waiting during a card game.

Design for Environment

Our major area about the impact of environment and the automatic card shuffler are batteries and the plastic body decompositions after throwing away.

In order to run the current automatic card shuffler, users will need to insert two "C" batteries. Most users will choose the non-rechargeable batteries to save the cost. After using for couple times, we need to buy and change another two batteries. Batteries contain hazardous materials that may get into the environment. For example, cadmium and lead enter soil and water from landfills and enter the air via municipal waste incinerators. Recycling the batteries has become an issue to normal users since it is not as easy as a can of soda. Batteries can be recycled at the household Waste collection facility which may not be convenient for most users. This will result people just throw it directly without recycling.

Using the automatic card shuffler without batteries will be a positive impact for the environment. The inclusion of a hand crank system would eliminate the need for batteries. We analyzed this concept but deemed it to require too much effor by the user, since one would have to crank multiple times or very fast to shuffle the cards efficiently. Other hand powered solutions seemed to defeat the purpose of an automatic card shuffler, as the user would have to repeat a motion many times to shuffle the deck. This would just complicate and lengthen the shuffling process by the automatic card shuflfer. We thought that the user would more likely just shuffle the deck by hand over using the shuffler if it had to be hand powered, so we ruled out hand powered solutions.

After users decide not to use the automatic card shuffler and throw it away, that is another potential to takes up space in landfills and become harmful to environment. Since plastics are so durable that they will not rot or decay as do natural products such as those made of wood. As a result great amounts of discarded plastic products accumulate in the environment as waste. It also presents the additional problem of being difficult to burn. We think by using the better material to help by producing less pollution is an important are for our product

Failure Mode and Effects Analysis

The following chart emphasizes the most sever failures that can occur with the product. Although none of these failures could cause a complete termination of the functionality of the product, they would cause the user to become completely dissatisfied with the product, thus coercing the user to stop the usage of the card shuffler. The point of this analysis is to ensure that the user is free from as many annoyances that would cause he /she to stop using the product.

Item & Function Failure Mode Effects of Failure S Causes of Failure O Design Controls D RPN Recommended Actions Responsibility & Deadline Actions Taken S* O* D* RPN*
  • Powers the gear train
Electrical failures: Motor may not output consistent power Product shuffles cards in an inconsistent pattern resulting in uneven shuffling. 7 Poor brand of motor. Poor connections between the motor and the wires. 7 Extensive testing in various conditions because environment setting could play a role 3 147 More effort in making more secure connections. Integrate better motors Motor Manufacturer N/A 7 5 3 105
Mechanical Failures: Wear & Tear. Loud noise and inefficient shuffling of cards . 7 Heat generation causing the teeth in the gears to deform and shear away at each other 2 Test in various conditions and record temperature with thermocouples 6 84 Change arrangement of gears to reduce power input required of motor Motor manufacturer N/A 6 2 5 60
Gear train
  • Transmits power supplied from the motor
Gear train is not snugged fit. Loose gears. Gears produce loud noise that is intolerable for the user. 8 Broad range for the dimension tolerance. 8 Run the gears to check for wobbling 6 384 Reduce the tolerance range for the teeth dimensions of the gears Manufacturer N/A 5 6 5 150

Gear Train Case
  • Incases the gear train set
Vibration on the card shuffler Wobbling of gears because the entire gear train set is vibrating. 7 Case not secure to the base of the card shuffler. 7 Test to see required force to hinder vibration 5 245 Glue the gear case to the base Manufacturer N/A 7 5 3 105
Conducting Wire
  • Transmits the current from power supply
Unsteady power output Inconsistent rotating of the gears. 5 gauge size of wire may not be sufficient enough. 7 Test with different wire types 3 105 Use bigger gauge of wire Motor Manufacturer N/A 4 6 3 72

The Failure Analysis is based more on how the product will not satisfy the user than the actual product breaking itself. We feel that the design of the standard card shuffler is simple enough to have a relatively low risk of acually failing. One thing we noticed was the inconsistent pattern of shuffling. This may be due to either poor motor input or poor connections with the wires. We noticed this because as soon as we opened the shuffler for dissection, the wires came loose from connecting points. One recommendation would be to have a more secure connection between the wires and the motor. Another may be to simply have a better motor than the one that was used but that is mroe of a manufacturing issue. Some of the noises that were heard were coming form the gear train. This may be due to high tolerance dimensioning of the gears and gear teeth. Lowering the tolerance range would allow for a more "snug fit" between gear teeth because we noticed wobbling of gears while they were running. In addition to the noise, there is also vibrating of the gear cases that incase the gears. Maybe if the gear cases were glued down to the base as opposed putting it in through translational fittment would reduce the vibrating of the gear train. An additional issue if failure is if the cards are shuffled without the tray in place. If this is done then the cards would be very difficult to remove since they would lay flat inside the shuffler. It would be difficult to reach in and extract the cards if no tray was underneat them to aide in lifting them out. We plan to address this issue with our concept designs.

Market Reasearch and Observations

We recently polled a random population about the use of a card shuffler to see overall interests and opinions about the product. We came up with the following data:

  • 85% of all the surveyed participants would be interested in a quieter operating shuffler
  • 20% have used or seen an automatic card shuffler in action
  • 44% said they would like to see a higher quality shuffler than the one we analyzed
  • 70% responded that they would be interested in a shuffler that would deal out the cards

Through research and testing on the shuffling pattern we found that the automatic card shuffler would shuffle very consitently and evenly. When repeated placing a set configuration of cards into the shuffler, it would output the same shuffled configuration every time. This raised an important issue of the randomness of the automatic card shuffler. Since the device would use the same algorithm to shuffle the cards everytime, it yields an output that is somewhat predictable. Card counters would even be able to successfully predict the order of the cards. We plan to address this issue with our concept designs.

Our observations of users operating the machine have also shown that using the card shuffler does not actually save time over hand shuffling. The average times was about the same since the user had difficulty removing the cards from the output tray slot, and then would have to separate the cards into two piles to place into the machine to shuffle again. Since the automatic card shuffler yields a set shuffle pattern as discussed above, the users would have to shuffle the deck many times to acheive an efficient shuffle. This overall process from beginning to end was about the same or sometimes longer than shuffling by hand.

Users also expressed concerns that the shuffler would produce wear and tear on the cards from the cards hitting the inside walls when being shuffled. Although we didn't notice any excess wear from using the shuffler over our period of research, we plan on implementing some dampening material to the sides which will not only soften the impact of the cards, but to lower the noise of the shuffler due to impact. We noticed that hand shuffling produced much more wear and tear to the cards than using the automatic card shuffler, as hand shuffling tends to be done by flexing the cards and shoving them together. This is much more strenuous on the cards than the automatic card shuffler since little actual force is applied to the cards to rearrange them.

Further Analysis and Conclusions

Improvement Areas, based on production observation, not necessarily in conjunction with our top concepts

  • Inner wiring configuration. One of the wires maneuvers very closely around one of the gear trains, which can easily be caught into and ripped.
  • Soldering contact points very weak, one of the electrical wires has already broke.
  • Using thicker, lower gauge wire might help with stronger attachments to soldering points.
  • Gears slide freely on their respective shafts. Not many people would take apart the gear train in the first place so having permanently attached gears would reduce premature wear from sliding along the shaft/misaligned teeth as well as help to reduce noise levels
  • Relocating the power button so that it is not infront of the card output tray slot
  • Altering the card output tray slot so that the cards are not completely inside the machine
  • Reducing the noise that the shuffler makes when operating - dampening material would also reduce the wear and tear of the cards as they come in contact with the sides of the shuffler when shuffled
  • Addressing the issue of the randomness of the shuffling

Top Design Concepts

Click the link below to go to our concepts page.

Card Shuffler Improvement Ideas

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