Difference between revisions of "Group 27 - Nerf Vulcan EBF-25"
Latest revision as of 14:35, 20 December 2011
To start our analysis of the Nerf Vulcan EBF-25 our group did an extensive amount of background research regarding the product. This research included price, material, competitive products, and many more specifics. It provided a basic foundation for the overall analysis of the product. However, the research provided only the initial step for analysis. The most advancement of our group’s overall project came once we purchased the Vulcan EBF-25. Following the purchase (including the purchase of batteries), we assembled the product. From there, we fully planned the disassembly of our product. The next step in the analysis process was to begin the actual disassembly. The full disassembly took around 1.5 hours. It consisted of taking 19 pictures and required the use of only two screwdrivers. The full disassembly is presented below under “Gate 2” in great detail. During the disassembly, our group fully learned the inner workings of the main functions and the subsystems of the Vulcan EBF-25. Preceding the disassembly, our group completed a component summary where we named and described each component of the product (found below under “Gate 3”). This also included an analysis of the four factors. After that, the group used the program Inventor 2011 to create full assembly views of the product. These illustrated the placement and sizes of the components. After the component summary, we formed a complete analysis of our product. Through this analysis, we brainstormed design revisions. We decided upon three which are described in great detail below under “Gate 3.” The final step of the project was “Gate 4.” This step involved the documentations and descriptions of the steps involved for reassembly. We used a table (below) that described the difficulty, quantity, and provided an image of each step. With the reassemble finished, our group moved on to final design revisions for our product. This was the final step for the project. In conclusion, the project resulted in several growths, findings, and outcomes. Through the five gates, our group transformed in several aspects. For example, at first the product was chosen based on the entertainment value of a Nerf toy. However, by the end our views evolved into creating improvements and learning from each others' ideas and thoughts. We gained the knowledge through the analysis process and formed a solid conclusion through the discussion step of the process. We concluded that the proper design revision would be to decrease the weight of the product and enable variable velocity of the projectiles through a variable power source that is lighter and more powerful. In addition, the front end of the Vulcan is unnecessary and only results in a higher cost and more weight. Therefore, the revised Nerf Vulcan EBF-25 would be lighter for children and more powerful for teenagers, thus expanding the market for the product.
Group 27's project for MAE277 is dissecting, suggested modifying, and analyzing the internal components of the Vulcan EBF-25 by Nerf. This process will be documented throughout the semester in formal reports in the form of five separate gates. The product is sold worldwide through a Hasbro product line. Product assembly is required after purchase. The price is 40 US dollars and batteries are sold separately. Thus, the total cost is around 50 American dollars. Fully automatic and manual fire are the two options for operation of the product. Initially released onto the market in 2008, the Nerf Vulcan now includes two three different colors/style. The Vulcan EBF-25 that will be analyzed is green and orange colored. Its components are almost solely plastic. The five gates are listed below accompanied with pictures and tables.
|Tom Petersen||Project Manager|
|Corey Bice||Research and Development/ Technical Assistant|
|Robert Hanes||Communication Liaison|
|Ryan Tomala||Technical Expert|
|Jason Cukierski||Financial Adviser|
The disassembly process is as follows: The time required for the total disassembly of the Vulcan EBF-25 is estimated to be between 30 minutes and 1 hour. As disassembly proceeds, the parts as well as any screws or springs will be noted and placed in an organized manner as to make reassembly as easy as possible. In the case that any parts are lost they will be replaced with a suitable alternative or the group will purchase a replacement part. There should be little trouble with the disassembly of the product and the only foreseeable challenges are going to involve the internal components such as the firing mechanism, the electrical components, and the cocking assembly/firing pin.
Remove all components that can be removed without tools:
- Remove the barrel by simply sliding it out (Held in by Friction).(Note – The barrel tip must be removed first which is held in by screws).
- Remove the carrying handle by turning the tabs/pins holding it in and unlock it.
- Remove the ammo box by opening the breech cover and simply sliding it off.
- Remove the ammo box cover by releasing the two tabs.
- Remove the tripod by pressing on the clasps and releasing it from the nerf gun.
- Remove ammo belt by pulling it out of ammo box.
- Remove the battery pack (Note – The battery door must be unscrewed and removed first).
- Pull apart the two halves of the cocking bolt and remove them, allowing for the gun casing to be pulled apart later.
Remove components that require a screwdriver:
- Remove two (2) screws and two plastic pins holding on the breech cover.
- Remove three (3) screws and pull off the power switch cover.
- Remove one (1) screw and pull the front sight out.
- Remove three (3) screws and pull out the barrel tip/cover.
- Remove one (1) screw and release the battery door.
- Remove three (3) screws and release the foregrip.
- Remove twenty five (25) screws and split the gun casing into two halves.
- After removing the outer casing there is access to internal components, the specific disassembly process of said components is currently unknown until the actual disassembly occurs. It is assumed that they will be similar to other steps and be able to be done with a Phillips head screwdriver or be taken apart by hand without tools).
- Remove four (4) screws and detach the tripod release head from the tripod.
- Remove four (4) screws and detach the plastic cover from the tripod pivot point.
- Remove eight (8) screws and separate the tripod into two halves.
- Detach two resistance springs by unhooking one end and then remove two (2) screws to allow the other end of the springs to slide off.
- Remove six (6) screws from front two tripod legs an detach them from the tripod assembly. (Note – In doing so, the gears used in the pivoting motion of the tripod are also exposed and separated.)
Note: All screws use the same size Phillips head screwdriver.
In order to meet the requirements of this project on time, our group plans on evaluating the work load and then dividing it into five equal sections amongst the members of our group. This way everyone is contributing an equal amount of work and fully participating in the project. In addition, we also will meet on Monday’s, Wednesday’s, and Friday’s for a minimum of two hours a day. The time frame for these days will be either the hours of 3 p.m. to 4 p.m. before class or 5 p.m. to 6 p.m. after class as well as counting any time that we may have in class from 4 p.m. to 5 p.m. If any of these times are inconvenient or if we need more time to work on the project we will meet on Tuesday, Thursday, or on the weekend at a time that is reasonable for all the members of our group. In order to keep all members of our group informed of the meeting times and updates on the project, we will assign roles such as Communications Liaison and a Project Manager. If there are any conflicts with the roles or responsibilities of each group member, the group will meet and discuss the issue and find a sensible resolution to the problem that everyone agrees upon.
The group roles and responsibilities are as follows:
- Organize the division of the assignment into equal parts and convene with the group to decide who will work on which part.
- Keep track of work progress on each part and the project as a whole.
- Make sure work is getting completed on time and is of acceptable quality.
- Review each assignment before submission to make sure that all aspects are thoroughly addressed.
- Make sure everyone attends meetings.
Research & Development/Technical Assistance
- Research the operations of the product as well as the operations of any modifications.
- Thoroughly compare and contrast multiple options when choosing modifications.
- Maintain thorough knowledge of the product and its components in addition to that of the Technical Expert.
- Maintain organized information and record data from the product and the results of modifications.
- Keep members of the group informed of the specifications of the product and its current operational status.
- Maintain open communications with instructors and TA’s and is responsible for asking/emailing any questions the group may have.
- Notifying the group members of the meeting times as well as any changes to said times.
- Reminding each group member of which part of the assignment they are responsible for and when it is due by.
- Responsible for proof reading the assignments before they are submitted to make sure that spelling, grammar, and punctuation are correct.
- May be responsible for writing up the final document from the separate parts, depending on the distribution of the work load amongst the group members.
- Maintain a full knowledge of the product and all of its components.
- Interface with the manual or any other technical documents before and after work is done on the product.
- Responsible for maintaining the products functions and regular operation.
- Research of modifications as well as their integration into the product.
- Keep track of any changes made to the product as well as their effects.
- Maintain an accurate budget for the group.
- Allocate funds appropriately for purchase of modifications or any other necessary items.
- Brainstorm possibly ways to generate funds if needed.
- Make assessment of cost-effectiveness of modifications and research the purchase of the most advantageous product.
- Communicate with Technical group members to plan a budget for obtaining intended modifications or tools.
To start to assess the Vulcan EBF-25 we will start from the barrel. The barrel is a long orange plastic tube that is grooved on the inside the long ways. This barrel in essentially useless, the diameter of the barrel is twice the size of the darts. This means that the effects of a barrel that would normally happen as in making the bullet travel farther and more accurate. As we travel from the tip of the barrel down the barrel we run into the plastic structure that surrounds the barrel and makes up the main structure of the gun. The function of this structure on the front of the gun is to give the user some place to hold the gun in order to aim. The top of this structure has aiming sights in the center as well as a clip to attach the guns many accessories such as a scope. Theses clips are also located on the sides. This structure also holds the barrel in place. Moving to the center of the main plastic structure it starts to have many more functions. In the lower part there is a compartment with a door that once unscrewed allows the placement of the batteries to power the product. Below this is a elevated oval surface that allows for the attachment of the tripod. The middle of the structure houses the feeding and setting mechanism for the the dart belt feeder. This feeder sticks out of the center and is shaped like a gear where the spokes of the gear stick out the bottom of the chamber. This gear rotates and feeds the belt through every shot. At this point there is also hole on the left hand side that looks like it was make by a ball being pressed in the side. There is a little lever inside this hole, this hole is where the ammo box is mounted on the product and the little lever holds it in place. Further towards the top of the structure there are holes on both sides that provide a place for the top handle to be mounted. Diagonal and above these is the breach cover which properly positions the darts in the chamber to be fired. This breach cover rotates on it connection to allow it to open the chamber in order for easier loading. Moving further back the gun the plastic structure houses all the firing mechanisms. A orange knob protrudes from each side of the product. This knob is connected to a rod running perpendicular through the gun. Using the knobs the rod is pulled back along a slit in each side of the gun. This motion also cocks the gun manually. That back part of the gun is shaped like a handle to make it easy for the user to hold. Protruding from the handle is a larger trigger about the size of two average fingers. On top of the plastic structure there is a large on/off switch. This switch is covered by a piece of plastic hinged at one end and attached to the main structure. This cover makes it so that during use of the product it is not accidentally turned off.
The Vulcan was released in 2008. The product was sold within developed countries such as the United States, Japan, and European countries. The Nerf product line has been highly controversial in these areas. It is said that such a product sends a message of violence within children in an already violently evolving world. The basis of Nerf products is not to instill violence. The Nerf products are meant to create a safe environment for children to play. The danger involved with the Nerf Vulcan is at a minimum with a chance of injury being very slight.
The intended use of the Vulcan EBF-25 is purely trivial. This product was made for the enjoyment of children. It provides a safer method for children to play together than with much more dangerous toys such as an air soft gun or a paintball gun. The Vulcan EBF-25 was designed as a toy and should be used as one. Children can find many different games to play with the Vulcan EBF-25, creating endless hours of entertainment for the group of children participating. This product was designed for use at home. The Vulcan EBF-25 can be taken outside as long as the weather is permissible. This product should be kept out of the workplace because it is a toy and unless they work at Habro; it would not be acceptable. The Vulcan EBF-25 performs the job of keeping children entertained. The parents of the children are then able to garner some time to perform tasks around the house and tie up any loose ends. This product must be used with some care as to prevent any injury to the users. If the children are too young to use the Vulcan EBF-25 then they could injury themselves quite easily. The children could choke on the projectiles if they are not watched or told explicitly. Children could also injure one another by striking each other with the guns so care should be taken when giving a child a Vulcan EBF-25.
The Vulcan EBF-25 uses a combination of Kinetic, Spring and Electric Energy to fire the darts quite long distances. The user supplies the Kinetic Energy through a lever that the user pulls back. The Spring Energy is created through the Kinetic Energy from the lever being pulled by the user. The spring compresses from the Kinetic Energy and builds up a quantity of Spring Energy that can then be used to launch the darts. Once the Spring Energy is built up the user can then trigger the gun to fire by pulling the trigger and releasing the spring and transferring the Spring Energy to the dart and then propelling it through the air. The Electric Energy can be used in lieu of the kinetic energy from six ‘D’ batteries. The Electric energy works in the same way that the kinetic energy propels the dart by transferring the energy from the battery to the spring and then to the dart except at a much quicker pace. The batteries can provide much more power than the user can so; the darts can be fired at a much quicker pace. With the electric power, the Vulcan can fire at a rate of three darts per second while the kinetic energy can only fire at a rate of one dart every three seconds.
Within the Nerf Vulcan product there are several components present. The forty dollar purchase includes- a tripod stand, 25 darts, a 25 dart clip, an ammunition casing, and the gun itself. The tripod stand consists of three plastic legs, each with rubber on the bottom for grip. One leg is stationary, but the other two are free to move forward and backward. This motion is controlled through two gears, one in each leg thus the legs can only move together. On top of the legs are two plastic pieces. These two are attached to a spring which allows the tripod to “clamp” onto the gun itself. The darts are simply a lightweight Styrofoam with rubber ends. The 25 dart clip consists of 25 dart holders made of plastic, bound together through a woven material. Each holder has a hole drilled through the backside, for the firing mechanism to come into contact with the individual darts. The gun is by far the most complex component. The Nerf Vulcan product has an automatic firing mechanism. This involves a motor, a power supply, a switch, and trigger. The power supply consists of 6 d size batteries. This power supply then goes to what I can imagine is a 9 or 12 volt motor which is activated through the switch on the outside of the gun. And finally the trigger releases the whole interaction of components, firing the darts consecutively.
The Nerf Vulcan product consists of several different materials. The main material is plastic, this accounts for about 75 percent of the product. The outside layer of the gun, tripod, ammunition casing, and most of the dart clip is plastic. Plastic is a relatively cheap material and provides a material that is durable enough for the Vulcan’s uses. All other materials are within the gun with the exception of the woven material used on the dart clip. This material is flexible and durable. This allows for it to be fed through the gun with ease and speed. The only other materials are the small components within the gun. These include screws which can either be a cheap metal or hard plastic. These are used to keep the components in place. The wiring in the gun and the circuit boards are held together by these screws. The wiring is typical wiring; perhaps conduit is involved within the gun, soldered to the circuit boards. These materials are all relatively cheap with the exception of the batteries and motor.
The user interacts with the Vulcan EBF-25 by using it as a toy and a tool while playing games with Nerf guns for entertainment purposes. Along with aiming and shooting Nerf darts from the Vulcan EBF-25, the user has to power the cannon with batteries and load the ammo belt that automatically feeds through the cannon. The Vulcan EBF-25 also comes with a deployable tripod that the user can mount it on or remove it. The user can also choose whether to shoot the cannon in semi-automatic or fully automatic modes. The product interfaces are rather intuitive. The principal of aiming and pulling the trigger to use the cannon is rather simple and standard with Nerf guns. Loading the ammo belt is also made simple with each Nerf dart having its own designated spot to be placed in the ammo belt, which then gets automatically fed through the cannon. The most complicated, yet still rather simple, part of the Vulcan EBF-25 is attaching or detaching the deployable tripod. The only regular maintenance that needs to be performed on the Vulcan EBF-25 is making sure it has electrical power by changing the batteries. Although changing the batteries is easy, it does require six size D batteries.
Product Alternative Profile
There are a lot of product alternatives that exist for the Vulcan EBF-25. Along with other guns made by Nerf, for example the Nerf Vortex product line, there are many other companies that produce guns similar to Nerf guns. Nerf also makes a line of water guns that could be considered alternatives called Super Soakers. The main advantage of the Vulcan EBF-25 compared to other Nerf guns is the fact that it is battery operated. This enables the cannon to load itself automatically and allow a faster firing rate. Another advantage that the Vulcan EBF-25 has over other alternative products is the fact that it allows the user to choose a semi-automatic or automatic firing mode. The deployable tripod that comes with the Vulcan EBF-25 is also a feature that is not offered by most alternative products. The only major disadvantage that the Vulcan EBF-25 has compared to other similar alternative products is its size. Compared to other Nerf cannons the Vulcan EBF-25 is rather cumbersome especially when the tripod is attached. Alternatives products in the Nerf N-Strike product line have some similar features compared to the Vulcan EBF-25. For example the Stampede ECS has a folding bipod instead of a detachable tripod, but the Vulcan EBF-25 is one of the few products that has its own automated feeding system. This feature of the Vulcan EBF-25 could be part of the reason that it is more costly than most other products in the N-strike product line. Generally, other cannons in the N-Strike product line range from $19.99-$24.99 but the Vulcan EBF-25 is $39.99 as priced on the Hasbro Nerf website.
|Nerf Stampede ECS|
The Vulcan EBF-25 should prove to be a great system to study the properties of Mechanical Engineering. It will be a challenge for the group to understand and document all of the processes that went into developing this product. The group will have to find consistent methods for developing a complete and accurate study of the Vulcan EBF-25. As long as the group works together and communicates well, there is no doubt that Vulcan EBF-25 will be broken down and understood.
Gate 2 consists of the removal and documentation of the components within the Nerf Vulcan EBF-25. This process is displayed thoroughly below, complete with descriptions and images of the 17 steps involved. Our group also documented the difficulty of each step, ranging from easy to medium difficulty. The tools used include three screwdrivers- one small flat head (1/8"), one small philips (1/8"), and one large philips head (1/4").
Cause for Corrective Action
Our group has been very successful with our work and management plans. Every member of the group has taken care of their tasks on time and with relative ease. Our technical expert, Ryan Tomala, has displayed prime knowledge of all the parts of the Vulcan EBF-25 while removing all of its components. Our Project Manager, Tom Petersen, has performed an excellent job by scheduling meetings when everyone can attend and making sure all of the work is being done on time. Our Financial Advisor, Jason Cukierski, has made sure that we have everything that we need or will need for each step of the project and makes sure that it is cost effective as possible. Our Communications Liaison, Robert Hanes, has done a wonderful job in keeping in touch with the TAs and professors by attending office hours and making sure that everyone knows which part of the assignment they are responsible for. Our Research and Development/Technical Assistant, Corey Bice, has thoroughly researched our product, which has greatly helped the disassembly of our product and made sure that everything was kept track of. Our work for Gate 2 started a few days later than anticipated but it was of no problem because our team worked more quickly than was forecasted. We predict that Gate 3 is going to take a lot of work, so our group is going to have to make sure to begin to work on it as early as possible.
Product Dissection Assessment
The difficulty of each step is documented above in the formatted table. Difficulty is assessed as one of three categories- easy, medium, or hard difficulty. Easy difficulty pertains to the removal involving simple tasks. These tasks include either unscrewing one to a few screws or a simple removal through unlocking geometry (such as sliding). Medium difficulty is a bit more involved, such as removing multiple screws and components. Hard difficulty is as follows. The step took several screws of multiple sizes and the removal of several components. In addition, the step took a longer amount of time and patients. These three categories should prove sufficient in documenting the difficulty of the steps. Specifically, a general trend occurred with the disassembly process. The hard difficulty was typically noted when the component involved in the step was not intended to be removed from the overall product (this is stated within the table above, when applicable). Evidence of this is when the component removal did not involve screws or other non-permanent manufacturing parts.
The subsystems of the Vulcan EBF-25 are connected through physical means. These include gears, wiring, springs, and custom plastic parts. In addition, a signal connects the two subsystems (main spring and feeder rotator). This signal is through the physical component of the trigger. In addition, this is evident through the electrical signal performed by the motor. These subsystems are connected for proper performance of the product. The means of this connection are a result of economic factors, economic in the sense of the cheapest means that still produce proper performance. As for the arrangement of the subsystems, this is influenced through social and global factors. The Vulcan EBF-25 is modeled after real live action weaponry. Therefore, the arrangement of these subsystems must be in an organized manor to account for the geometry of the product. As a result, the subsystems are connected and located in very close proximity within the Nerf Vulcan EBF-25.
Project Management: Coordination Review
Cause for Corrective Action
Our group has been working very well together and we have made sure that we have addressed any problems. For gate 3 we were a bit confused on how to show the components being assembled in sequence. We solved this problem by attending office hours to find out how exactly we were supposed to do the assembly. The TA showed us how to put all the parts together in an assembly drawing. Our group almost had the right idea but we had forgotten a few key components since taking MAE 177. Another problem has been dividing the work into equal workloads. We were able to solve this problem by spending a portion of the group meeting deciding who would do each part and how they would do it. In gate 3, we had to break to figure out how we were going to finish it in time. We did this by breaking up each category and assigning to one group member who would send it to another group member to check it over to make sure it was satisfactory. For example, Ryan was assigned to do the solid modeled assembly part of Gate 3 and then he sent it to Jason to make sure that it was done correctly. Another problem that the group had to deal with was the large number of tests that took place in the two weeks before Gate 3 was due. We knew of this problem before all of the tests so, we made sure to work on Gate 3 before the tests so we would have enough time to make corrections before the due date. The group does not have any outstanding challenges at this time and we will continue to deal with any problems in the future with diligence and perseverance.
Product Archaeology: Product Evaluation
The product was created as a result of several factors and assessments. These consist of component function, component form (geometry, material, and appearance), manufacturing methods, and component complexity.
The product was created as a result of several factors and assessments. Of these, the main analytical interpretations consist of the Manufacturing Methods and the Four Factors involved. There are many methods for manufacturing. However, for the specific product of the Nerf Vulcan EBF-25 the main method is injection molding. This process is used for the external plastic coverings, small components (including the trigger, sight, barrel, internal firing mechanism, and gears), tripod, ammo box, and ammo belt. These components were formed through a mold, filled with a green plastic. This is apparent through the plastic material used, the various shapes within the product, and the fact that plastic is a great material for injection molding. The Vulcan EBF-25 uses plastic throughout, roughly 95%. Therefore, injection molding is the best manufacturing process. In addition to injection molding, the manufacturing process of drawing was used. This is evident in the wires. Wires are formed and shaped through the drawing process.
The Four Factors
The price of the Vulcan EBF-25 was a large factor in deciding the process for manufacturing. Injection molding was the obvious choice for the plastic parts due to the high volume of parts needed for each gun. This would minimize the cost of each gun and would make it affordable for any child who wanted one.
The way in which society views the manufacturing process had a large impact on which manufacturing process was chosen. If society had a negative view on the process then they would most likely choose a different process so Habro would not receive any negative media attention.
If a product looks 'cool' or not was a large determining factor in deciding which manufacturing process to use. If the product does not look 'cool', then it would be a large turn off to the customers due to the nature of the product. Injection Molding was the obvious choice due to the fact that coloring the individual components would be much easier.
If the process was detrimental to the environment then Hasbro would want to choose a different process to avoid receiving any negative media attention. Injection molding is better for the environment because there is only one mold needed for each part so there would be less pollution.
Solid Modeled Assembly
Using the Inventor 2012 3D Drafting Program, our group modeled an internal assembly of the Nerf Vulcan EBF-25. This assembly consisted of four components- the seven gears, the main spring, gear shaft, and dart feeder rotator. Images of the assembly are shown below.
A key component of the Vulcan EBF-25 is the main firing spring. Without the main firing spring the Nerf gun would be absolutely worthless because it could not perform its main function, which is to shoot darts. It would not matter if electrical or kinetic energy was applied to the rest of the gun; the dart would not be able to be fired because it supplies the spring energy, which is the main energy that powers the dart through the air. The engineering analysis process would be used to find out which spring would be most appropriate for the Vulcan EBF-25. The engineers would not want a spring that would be too strong for the children using the Vulcan EBF-25. If the spring was too strong the product could fire darts with too much velocity and might become a liability for the Hasbro. The first step would be stating the Problem, and the problem is finding the right spring for the Vulcan EBF-25. Then a diagram would be drawn up showing the different forces on the main firing spring and how each one would effect the spring. Making some assumptions such as no energy is lost from the spring to the dart would be the next viable step in the analysis process. Then any relevant equation would be brought up such as the energy equation for a spring (U=1/2k(X2(^2)-X1(^2))), Hooke’s Law (F=-kx) and Conservation of energy (Ein=Eout). The calculations would then be performed to find the appropriate strength of the spring for the Vulcan EBF-25. Once an appropriate strength for the spring has been found the spring then would undergo a series of rigorous tests to make sure that it would live up to Nerf’s standards. Some of the tests could be making sure that it is durable enough and that the gun can fire as quickly as needed with the spring. If the spring does not pass these tests then the process will be need to be looked at and make sure that it is corrected. This step is the solution check and it must be done or the reputation of Hasbro could be damaged. The last step would be to present the spring to the person or persons in charge and discuss why it is the most appropriate spring for the Vulcan EBF-25.
The Nerf Vulcan EBF-25 is a well rounded product. Its components (in sequence and parallel) accomplish the aspects involved with a projectile launcher. However, the design could be improved. These improvements involve three major components- the main spring, power source, and motor. The improvements involved with each aspect is explained in detail below.
One component of one of the major subsystems that operates within the Vulcan EBF-25 is the main spring. We found that the main spring that comes standard with the Vulcan EBF-25 was rather frail to begin with but obviously strong enough to do the job of launching a dart. While testing the Vulcan EBF-25 we found that when lofted at approximately a 45-degree angle with the ground the darts were only launched about 25 feet at maximum, with some darts barely reaching 20 feet. So not only is the power of the spring unimpressive, it is rather inconsistent as well. Incorporating a stronger spring into the product would improve the users experience with the product by allowing it to shoot farther on average and having an almost negligible rise in production and retail prices thus providing a better product for the consumer.
One of the first things to be noticed about the Vulcan EBF-25 is the excessive size of the battery compartment. The main reason for the battery compartment being so large is to account for the size of the six size D batteries used to power the Vulcan EBF-25. One of the best ways to improve the power source for the Vulcan EBF-25 would be to replace all six D-batteries with one rechargeable 9.6 Volt battery pack. Since the six D-batteries provide approximately 7-9 Volts, not only would a single rechargeable 9.6 Volt battery pack provide more voltage but would take up less space as well. In addition the user would not have to go through the hassle and expenses of buying, changing, and properly disposing of batteries when they run out. So not only would the consumer benefit from this redesign but the environment could possibly benefit as well.
Another design revision that could be made to improve the Vulcan EBF-25 would be to use a different electric motor. Using a better, more efficient electric motor that could power the gun and still launch the darts at the same rate would reduce the battery usage for the Vulcan EBF-25 thus saving the consumer more money. Although this would drive up production prices making consumers pay more for the initial cost of the Vulcan EBF-25, the recurrent costs of continually replacing the batteries would be lower which is relatively high compared to the cost of the product.
Project Management: Critical Project Review
Cause for Corrective Action
Our group continues to work well together through all of the struggles and growing pains. One of the problems that we have dealt with was when we received our gate 3 grade. Our group believed that we were unfairly graded, so we attended office hours to talk to Mr. Olewnik about getting a re-grade. We also wanted to make sure that we were going to get a better grade on gate 4 as compared to gate 2. Another problem that we are going to have to deal with is making sure gate 5 is going to be completed on time. Gate 5 is due during finals week so it is going to be difficult to make sure that everyone does their part during that chaotic time. Another problem will be choosing the group member who is going to give the final presentation. Everyone will have to do their part to create the five minute presentation and we will have to decide which group member will do the best job of giving the presentation. Our group will have to continue to persevere through the most difficult time of the semester in order to finish the project and have a good grade.
Product Archaeology: Product Explanation
- Cocking Mechanism:
One design revision at the system level would be to redesign the cocking mechanism. To make it more efficient, we would make the cocking mechanism easier to cock back. We could do this by making the bolts in the cocking mechanism less resistive to the force required to cock the gun while still maintaining its full power. The Vulcan EBF-25 is mainly handled by children under the age of fourteen so, making the cocking mechanism easier to cock back would improve the overall performance of the product. The cocking mechanism is rather difficult to pull back even when handled by an adult. Through testing the product we have concluded that the cocking mechanism would be difficult for a child to apply a force necessary to cock back the gun. This addresses a societal concern for the Vulcan EBF-25; children could potentially hurt themselves from being too tired from cocking back the gun. This redesign would also address a global concern because the product would gain a more favorable view in a society’s culture. This redesign would bring more joy and children would get more enjoyment out of the Vulcan EBF-25.
- Barrel Length:
One design revision at the system level would be to reduce the overall length of the firing barrel. The length of the firing barrel is there purely for aesthetics only; it serves no purpose in the overall function of the gun. When we removed the barrel we tested the gun by firing it and found that the darts went exactly the same distance. Reducing the length of the firing barrel would improve the overall performance of the Vulcan EBF-25 by making it more maneuverable because the gun would be less long. This would also reduce the number of products broken from use because the barrel is the weakest part of the Vulcan EBF-25 so, by reducing its length the durability of the barrel would increase. This change would address an economic concern for the product, because it would reduce the overall price of the Vulcan EBF-25 since there is less material being used in the product. This redesign also addresses an environmental concern because it would reduce the overall emissions required to produce the product since there is less material being used. Since the Vulcan EBF-25 is becoming more maneuverable, it is also becoming a safer product to use because children are less likely to run into objects with a smaller gun. This redesign therefore addresses a societal concern since it is becoming safer.
A third design revision at the systems level would be to use a different motor or change the existing motor in a way to increase operating speed and power threshold levels. The current motors used in the Vulcan EBF-25 have been known to eventually burn out over time or burn out even quicker if any modifications are performed to increase battery power supplied to the motor thus increasing shooting rates. Although the motor can handle the extra power from the batteries temporarily, after a longer period of time the motor will eventually burn out because it is only designed to operate on about 9 Volts of battery power. So this factor somewhat limits the performance capabilities and modification potential of the Vulcan EBF-25. Using a bigger or better motor that can operate normally at a power level higher than 9 Volts, without burning out, will move the gears quicker and allow the Vulcan EBF-25 to shoot more darts per second. This revision would be considered a social design consideration because the manufacturers would be producing a better performing product that is more fun to use for the consumer at a reasonably small rise in production and market cost. Utilizing a motor that could operate safely at 12 Volts and could shoot at about five or six darts per second (compared to the currently claimed three darts per second) would almost double the performance rates of the Vulcan EBF-25 for the cost of a small increase in production price.
To define a meaningful scale for difficulty we determined it by the amount of effort that needed to take place in order to do the task. The scale is done on an easy, medium, or hard basis. The easy parts would include using basic tools for basic function such as screwing a screw or such things as pushing one part into another using a moderate amount of force. Medium parts would be something like holding a part a certain way while it is screwed into place. A hard assembly part would be something that one would have to hold under tension, hold multiple parts at once while being screwed in, or thread a part through or around stationary parts. The product was most likely assembled by workers on an assembly line with numatic screwdrivers. The assembly is the same as the disassembly just in the reverse order and only using a small and large Philips head screwdriver.
Gate 5 consisted of an overall summary and analysis, as well as a documentation of the information gained throughout the entire project. It is located above at the very beginning titled Technical Report. Within it consists Group 27's cumulative report of the Nerf Vulcan EBF-25. Through the five gates, our group has chosen the following improvements for the Nerf Vulcan EBF-25.
These improvements have been formed based on the four factors- global, societal, environmental, and economic. In a global and societal sense, the product will be cheaper. As a result, the product will be much more popular in different countries, regions, social classes, and ages. Also, the product will be lighter. Therefore, the product reaches a wider age market. The lighter weight allows for younger children to operate the toy. In addition, the product will be more powerful (with adjustable power). This will also expand the market, appealing to an older crowd for the more entertaining aspect. As for the environmental factor, this is addressed through the battery pack. With the battery pack installed, the replacement of batteries is removed from the product. Thus, there are less used batteries being thrown away. Also, with the less material being used within the product, there is less environmental damage that occurs through excavating and refining the material. As for the final factor, the economic value of the product increases with the improvements above. The economic factor is positively impacted for both the consumer and manufacturer. With less material, the manufacturing cost is decreased. This is a result of the battery pack decreasing the necessary manufacturing geometry (the product will be smaller). As for the consumer, with the battery pack installed the need for expensive d batteries is eliminated. This will save the consumer around ten dollars for every replacement of the batteries. Most importantly, with the improvements listed above there will be a rise in sales. The product will appeal to the consumer in every factor positively. In conclusion, through this project our group has provided a solid foundation for improvement incorporating the current potential of the Nerf Vulcan EBF-25. However, further research is required for a complete analysis, and decision on the future direction for the Nerf Vulcan EBF-25 product.