We’d like to thank all of the new students that stopped by our table at the Student Org. Fair last Friday to see what SuperMileage is all about! We talked to a lot of prospective team members who showed great interest in building an awesome car this year. The team relies on a constant rebirth of the team every year as people move on from the team to senior designs. We’ve got a lot of big plans for the year and some great talent coming onto the team.
We had an incredible amount of interest at our first Monday meeting this week as well! The small lecture hall that we were in was completely packed! Seats ran out and people sat on the steps. Everyone came down to the shop to check out the two vehicles and the design lab where we will be spending a lot of time this year, designing and fabricating a vehicle to achieve greater than 1000 miles per gallon.
This Saturday, September 21st, we will have our first “work day", where we will begin working on planning and budgeting for the build year. We will also be having a cookout for the team to get to know each other a little better. If you plan on showing up, we will be meeting on the 3rd Floor of the CC Building. We hope to see all of you there!
It’s the start of a new year for Supermileage and the perfect time to recap what happened over the summer, including our last competition at Eaton! On June 5th, we left Milwaukee on our way to Marshall, Michigan for the SAE competition. We left Milwaukee at 2 A.M. letting us arrive in Marshall around 8 in the morning. The team arrived in Marshall, groggy but ready to put the few final touches on the car. The MSOE students worked hard all day long to prep the body of the car and get some engine testing in and worked late into the night.
First day of Competition (June 6th):
Arriving at the Eaton Proving Grounds at 8 in the morning, the team set about prepping for tech inspection. There was still much to do before making it through inspection. Mirrors were mounted, the CVT was adjusted, the engine was tuned, the body was placed on the car; all finished before the days end. By the end of the day, the vehicle was nearly ready to go through tech inspection.
Day Two of Competition (June 7th):
Day two started off rough. The team had worked late into the night tuning the engine and making small adjustments to it. Halfway through the day, the team finally started the difficult task of tech inspection. Armed with the knowledge that the judges were inspecting every small detail of the car. The team breezed through the inspection process until only 3 items were left on the list for inspection: actually starting the car, the slalom course, and the brake test.
Starting the car proved to be more difficult than imagined. Unbeknownst to the team, one of the wire in the electronic control unit (ECU) had come unplugged rendering it impossible to start the car. Two minutes before the crew at Eaton were going to close down inspection, a ray of light appeared in the sky. (Both in the literal and figurative sense of the word.) A last ditch effort led to the plug being insert back into its respective outlet and the engine roared to life when the start button was pushed. Finally, things were looking up.
The slalom course and brake test were finished in minutes and the car finally made it out on the track, being the last car allowed on the track.
The MP-680 ran smoothly until lap 4. The car drove around Turn 1 and was not seen again. Went the car did return, it came back on the back of the truck affectionately known as “The Reaper.”
Although we did not finish a complete run, we didn’t leave the competition empty-handed. At the award ceremony, the team was surprised to find out that they had won first place in the design report. We also left with the knowledge that efficiency can always be improved and that next year’s team would have a great platform to start working on improving the car.
At the beginning of April, the Supermileage Vehicle Team competed at the Shell Eco-Marathon, a fuel economy competition held by the Shell Oil Company in Houston, Texas. The team drove 24-hours to get to Houston and compete with their two vehicles, MP-82c and MP-680. Below is a view of the Shell Eco-Marathon track at Discovery Green as seen from the 9th floor of a hotel adjacent.
The first day of the competition served to allow teams to pass through technical inspection and work on their vehicles, with the next day for practice and the final two days used for competing the vehicles on the track. Below is a picture of our older vehicle, MP-82c, going through technical inspection.
At the end of the first night, tech inspection closed with MP-82c nearly getting through. Working tirelessly for the rest of the night left the team feeling pretty tired.
The rest of the first evening was spent working on the engine tune for the MP-82c’s fuel injection system, which the team was able to get running steadily. Day two was a practice day, meaning that all teams that got through technical inspection could get out on the track and test their vehicles, despite no official fuel measurements being taken. Both of the vehicles still had to make it through technical inspection, and eventually did, but not before the track was closed for the day. Passing tech was extremely rewarding for the team, leaving them prepared for the next day as the competition began.
On Saturday (day one of competition) both of the vehicles were brought out to the lengthy starting queue to await track access. The cars were fueled and able to get out on the track. Here is the MP-680 leaving the starting line (without the yet-to-be-completed body shell).
Unfortunately, on the 6th lap of 10, the MP-680 experienced a complete lock-up of the steering system and was unable to complete the run. Luckily the malfunction caused no harm to the driver, Pat, who was able to safely exit the vehicle and with the help of the event organizers get the vehicle back to the paddocks where the team was working. Here is Pat next to the vehicle after the failure.
The MP-82c was able to complete one successful run, while nearly completing several others. On one particular run, the external kill switch was accidentally activated during the run, causing the vehicle to shut off completely and disqualify the run. Another run saw the fuel system leak and cause the engine to shut off. After these two runs, the team was not able to get another attempt before the end of the competition. The vehicle achieved a total fuel economy of 522.7 Miles Per Gallon. Here is that vehicle during its successful run.
After returning from competition, the team has been working hard to get MP-680 ready for the SAE Supermileage competition held on June 6th and June 7th in Marshall, Michigan at the Eaton Proving Grounds. Problems that arose during the Shell Eco-Marathon are being examined and fixed, which include some major renovations to the steering assembly and fuel delivery system. The cylinder head and engine block are getting some attention, such as lapped valves, new gaskets, and other upgraded components to prevent issues in the future. The custom-built throttle body is nearly finished, effectively converting our engine to fuel injection. Following its installation, extensive tuning of the engine control unit (ECU) will prepare the engine for efficient performance in the MP-680 come June. Another huge endeavor being undertaken is the construction of body molds to begin laying up the carbon fiber shell. The body molds are being constructed layer by layer using 1-inch foam insulation, which will be plastered, painted, then brought to a smooth finish before carbon fiber layup begins.
Stay tuned, and we will keep you updated as we prepare for our upcoming competition!
Fuel efficiency is one of the most important and hotly debated topics within the automotive industry. Owning a fuel efficient car saves you thousands of dollars over its lifetime, protects our valuable natural resources, and keeps our air clean to breathe. Recently the White House passed legislation requiring the average fuel efficiency (or fuel efficiency equivalent for alternative energy vehicles) of cars and light-duty trucks to be at least 54.5 miles per gallon by the 2025 model year, over two times higher than the current fuel economy average around 24 mpg. This push toward high efficiency benefits everyone, but what exactly makes a car fuel efficient? What steps do automotive engineers take to increase the number of miles a car can travel with a gallon of gasoline? How can you improve your own fuel efficiency?
A closer look at efficiency
Efficiency is a concept in thermodynamic science (the study of energy) that’s defined by the ratio of the desired energy output to required energy input, or “want” divided by “cost”. For a car, the energy “cost” is the heat produced by burning gasoline in the engine and the “want” is the energy that actually goes into moving the vehicle. The less gasoline you burn to move your vehicle, the more efficient it will be—a concept that we’re all pretty familiar and comfortable with. There’s another concept in thermodynamics called Carnot efficiency. Carnot efficiency governs the maximum possible efficiency for an engine, a car’s engine is limited to about 65% efficiency—and that’s pretty much the absolute best possible efficiency. 65% efficiency means that for every 100 Joules (the metric unit of energy) produced by burning gasoline only 65 Joules are able to be used to move the vehicle. There are several factors that limit this number even further—down to around 30%—including heat lost through exhaust, heated radiated from the engine block, air resistance, and friction in the mechanical systems that transfer energy from the engine to the wheels.
Ways to improve efficiency
A couple of the most common and easiest ways for engineers to improve the efficiency of vehicles are completely separate from the engine, but there are also several recent changes to engine design that have helped us work toward more efficient cars. Let’s look at how we’re able to improve efficiency of a car.
A significant portion—as much as 60%—of a car’s energy is used to overcome the effects of air resistance. Air resistance occurs because the vehicle has to physically push air molecules out of its way to travel. It requires energy to move the air particles, and this energy is provided by the engine. Mathematically, air resistance is determined by the aerodynamic drag equation, which says that the size of the vehicle, its speed, and its shape all affect how air flows around a moving car. If you have two cars that are identical in every way except that one is half the size of the other, the smaller car will have half of the air resistance of the larger vehicle and will lose half as much energy from pushing the air aside.
The shape of the vehicle governs a property called the drag coefficient, a number that is very important in the design of all types of vehicles—from the SuperMileage vehicles to Formula One racecars. The lower the drag coefficient, the less energy is required to move the vehicle. Many production cars have drag coefficients around 0.35. Some examples include the Toyota Prius, with a drag coefficient of 0.25, the Cadillac Escalade, which has a drag coefficient of 0.36, and the Smart Fortwo with a drag coefficient of 0.38. These numbers show that Escalades have a more aerodynamic shape than Smart Cars—a surprising fact!
Most people have a general awareness of what makes a vehicle aerodynamic. You probably realize intuitively that smooth, round shapes are generally better than boxy shapes, a fact that, although intuitive, has been scientifically proven. Engineers use scientific concepts, mathematical equations, and specialized software called computational fluid dynamics (CFD) to determine the drag coefficient of a vehicle design and to tweak designs to produce the optimal vehicle shape.
Reducing the weight of a vehicle is also a significant matter in increasing fuel economy. It’s generally understood that lighter vehicles use less gasoline. There are several reasons for this—heavier vehicles experience higher friction and are harder to get moving. They also have higher kinetic energy, or the energy of movement, when they are moving than light vehicles have. This kinetic energy is completely lost when the vehicle stops. Because of this a 5000 pound vehicle that stops from 30 miles per hour in 200 feet loses twice as much kinetic energy—initially generated in the engine—as a 2500 pound vehicle that stops from 30 mph in 200 feet. To make vehicles lightweight and to reduce losses, engineers have been able to replace steel with lightweight materials like advanced plastics, fiber glass, carbon fiber, and aluminum in the body and frame designs of cars. These materials can be several times more expensive than steel, but reduce the weight and fuel consumption significantly.
Create efficient controls and comfort systems
Vehicles lose energy when moving due to the tires, suspension, steering, and electrical. A large portion of losses in these areas are due to rolling resistance in the wheels (friction between a rolling object and another surface). Steering the vehicle uses energy from the engine to power hydraulic systems that make steering smooth and easy, and electrical components, such as air conditioning, lights and radios use electricity produced by the engine and converted in the alternator. Energy is also lost through the suspension system when the vehicle stabilizes after hitting a bump. These losses can be further minimized through efficient design and proper conditioning and alignment, but are close to being minimized already.
Improve engine efficiency
Recently, new and improved engine technologies have emerged that have allowed fuel efficiency to increase significantly. These technologies will be important in reaching the government’s goal of an average fuel economy of 54.5 mpg. Almost every gas-powered vehicle currently made uses electronic fuel injection (EFI) with computerized variable-ignition timing (VIT) to decrease the amount of gas wasted inside the engine. Traditional technologies, like carburetors and mechanical ignition timing, can allow for too much or too little gasoline to enter the cylinder of the engine, resulting in gasoline being rejected from the system without ever burning. Obviously, this wastes gasoline and is harsh on our atmosphere, so EFI has been a welcome change in the automotive industry. Some engine technologies traditionally used to increase an engine’s power have recently been used to increase the efficiency of engines as well. A major example is turbo-charging. Turbo-charging an engine can increase performance statistics all around—faster speed, more power, better acceleration, and higher fuel economy (if you can keep your lead foot from getting the best of you!). A turbo takes energy from the exhaust gases to rotate a fan that forces more air into the engine’s cylinders, which promotes improved burning of the gasoline in the engine.
Other technologies, like gas-electric hybrids have already made a huge impact on the automotive market and will continue to be a major key in improving fuel efficiency. One type of a hybrid system is designed to keep the engine running at its optimal speed for the highest possible fuel efficiency. This significantly improves fuel economy and reduces gasoline used. Hybrids are still at a point where they may not be financially viable for many consumers, but are steadily approaching a point where they will be available to all consumers as prices drop and as used hybrid vehicles become available. Plug-in electric vehicles can take advantage of more efficient and cleaner power production systems like wind power and solar power that have minimal carbon footprints and are much better for the environment than gasoline engines. These technologies are still in their infancies and have a long way to go to until they are able to be dominant in the automotive industry, but will be a major player in the future.
Technologies the SuperMileage Vehicle utilizes
Students on MSOE’s SuperMileage Vehicle team take all of the inefficiencies listed above—and more—into account when designing a new SuperMileage Vehicle. Size is minimized, weight is minimized, and the body shape is optimized for low air resistance, with a drag coefficient around 0.1. The steering system and drive-train system are both optimized for minimal losses due to rolling resistance and power transmission, and are simplified to reduce the locations at which energy is lost. The vehicle’s engine, a stock Briggs and Stratton 150cc lawnmower engine, is carefully redesigned with EFI and tuned to optimize efficiency. State-of-the-art materials, such as carbon fiber composites, are used to create strong, light parts for the vehicle wherever it is possible.
Perhaps the largest factor in the SuperMileage Vehicle’s fuel efficiency is the driving technique. The driver of the SuperMileage Vehicle drives with the engine off for the majority of each run. Since no gas is burned with an engine turned off, this is one of the easiest ways for us to improve our fuel economy. The driver has complete control over the engine, allowing the engine to be turned on and off while driving. (This is not recommended for your vehicle!) For the newest vehicle, an electronic readout is being designed to allow the driver to see a live feed of performance statistics, including real-time fuel economy. This will allow the driver to actively interpret the data to determine the best way to minimize fuel consumption.
How you can improve your own fuel economy
With all this talk of improving fuel efficiency, you’re probably wondering how you can improve yours without buying a new car or making major changes. One of the biggest factors that you can adjust is your driving technique. Accelerating at a moderate speed and slowing down earlier when you know you have to stop go a long toward improving fuel economy. Using your brakes as little as possible (without breaking any speed limits, of course) will help your vehicle to keep the energy that the engine produced. Accelerating too fast will burn more fuel than necessary, and accelerating too slowly will also burn more than you need to. Most new vehicles have a real-time fuel economy readout much like the SuperMileage Vehicle has. Simply paying attention to your miles per gallon will help you to understand what driving techniques and strategies will help you to save gas. Good driving technique can even improve your fuel economy by about 5 mpg!
It’s up to you and us to keep pushing toward reaching the goal of 54.5 mpg by 2025. We need to work hard together to create vehicles that keep our atmosphere clean, our fuel costs down, and still provide comfort, fun, and luxury. Going green doesn’t have to be a boring process that you’re unwillingly forced into, but can be an exciting way to work our way into a clean and bright future!
Written by Mike Fricke, second-year team member, Steering Design team leader, Sponsorship Manager, and Vehicle Driver.
As 2012 ends and 2013 begins, the SuperMileage Vehicle Team has made considerable progress towards the design of the new SuperMileage Vehicle, code-named MP-680. The 2012-2013 team is shown in its entirety below! For more about the team, please visit About the Team. Many of the designs are currently being finalized and the team is preparing to move into the fabrication phase of the vehicle. Below are the current developments of the team.
The team plans to compete at the Shell Eco-Marathon in Houston, Texas in April 2013 with two vehicles: MP-82c (The vehicle that was initially constructed during the 2010-2011 academic year and competed with in 2012 at the Shell EcoMarathon) and MP-680 (the newest vehicle being designed by the SuperMileage Vehicle Team). This allows more of the team to travel to Houston for competition, as only eight people are allowed per vehicle. This also allows the team to continue to improve the previous vehicle while starting a new vehicle to use previous experiences and reapply them to push the boundaries of fuel economy. The design updates at this point will be discussed in detail below.
The body team’s goal for the new vehicle is to reduce the vehicle’s drag coefficient as much as possible while accommodating all necessary vehicle components such as the driver, chassis, steering system, etc. In order to reduce the vehicle’s drag coefficient as much as possible, the body team will use Computational Fluid Dynamics (CFD) in ANSYS 14 to calculate a theoretical drag coefficient.
Designs for the body began in the two-dimensional spectrum, where several profile shapes were compared. The first profile used was a circle, which would allow for the CFD results to be validated. The second of these profiles was the Kamm Tail, a truncated aerofoil developed in the automotive industry and distinctly visible in vehicles such as the Toyota Prius. The Kamm Tail works by following an airfoil shape to a point, after which all material is removed, which is able to, in a sense, “trick” the air into following an aerofoil shape. This can be seen in the image to the right showing the CFD result for a Kamm Tail at 5m/s. This gives better performance in cross winds, where there will be markedly less flow separation.
The other profile in the comparison was a traditional aerofoil shape. This shape performed better in CFD testing, yielding much lower drag coefficients. At this moment, the body design for the MP-680 vehicle is nearing completion, as many of the other teams are finishing designs that the body team must fit within the shell of the vehicle. The current design is shown to the right side (two wheel wells in front and one in the rear). The molds for the body will be graciously donated to the team by Midwest Composite Technologies.
The chassis team’s goal for the new vehicle is to design a light-weight chassis utilizing composite materials such as carbon fiber. The team has been hard at work and has gotten much accomplished. In October, the chassis team constructed a wooden mock chassis to test the stability on an incline (to verify that their design would comply with competition tilt-test rules). The chassis design performed well, and the designs were finalized afterwards. The design is centered around a twin-rail system utilizing two-inch square tubes made of carbon fiber—donated to the team by Trek Bicycles—that will run the length of the chassis. This system was chosen for its simplicity, strength, and light weight, compared to the aluminum chassis of the previous vehicle.
To test the carbon fiber, an MSOE professor lent their expertise and helped to run compression and stress concentration tests. The carbon fiber tubes performed incredibly well, maxing out the machine when compressed, and cracking slightly under a point load of around 800 pounds in a beam deflection test. To the right is a picture of the beam after the point load deflection test.
The chassis team has also finished a roll bar design, using the knowledge of MSOE professors and basic FEA in the SolidWorks 2012 CAD package. The roll bar was designed to be as compact as possible to keep the body profile small while still meeting the necessary safety requirements of the roll bar. Moving forward, the chassis team will begin to fabricate their chassis, beginning with cross-members for their twin-rail chassis.
The steering team this year is working to improve the steering system in the vehicle. The new design intends to nearly eliminate wheel scrub (which increases rolling resistance) and to achieve the Ackermann steering geometry (which reduces the need for one wheel to slide while turning). In an Ackermann geometry, the wheel axes always point towards the center of the turn by having the inside wheel turn more than the outside wheel. A CAD model of the new steering geometry is shown to the left.
The steering team is also redesigning the steering wheel assembly and mounts for the front wheels to accommodate the new chassis design. The car will again have disc brakes—generously donated by HB Performance Systems, Inc.—on the front wheels, and a caliper brake on the rear wheel to comply with Shell EcoMarathon rules. To the right is team member Michael Fricke machining a piece to hold bushings for the front wheel.
The engine team’s largest goal for the vehicle this year is to develop a working fuel injection system for the 50cc engine (the engine used in MP-82c last year to achieve 842mpg). This task involves designing an air intake for the engine with appropriate mounting for a fuel injector. A CAD model of the intake is shown to the left. They will be working extensively with the electrical team to get the fuel injection system up and running, utilizing a Megasquirt for the Engine Control Unit (ECU) and fuel injectors donated by Mercury Marine. This ECU allows the ability to control the fuel injection as well as variable ignition timing, if time permits.
The engine team is also designing a pressurized fuel delivery system to comply with the rule in the Shell EcoMarathon competition that forbids the use of an electric fuel pump. The system utilizes a pressurized soda bottle whose output is regulated to the desired pressure for the fuel injector. They plan on using this system for both vehicles. The team expects a greatly improved fuel economy with a fuel injection system in place.
The drive-train team’s goal for this year is to change the system configuration from a fixed gear ratio to a Continuously Variable Transmission (CVT). A large benefit of the CVT is that it will enhance the burn-coast strategy used by the team by allowing the engine to accelerate faster while maintaining a constant RPM. This RPM can be set to allow the engine to spin at an ideal speed, maximizing the efficiency. The CVT will keep the engine from getting bogged down at low speeds like it did with a higher gear ratio. A picture of the CVT being lined up with the engine is on the right.
The drive-train team is also working on the arrangement of the vehicle’s power-train (engine and CVT) to minimize the space needed while still allowing proper engine performance. The team is also finalizing their decision for a rear-hub for the vehicle to maximize the efficiency by reducing the hub’s rolling resistance as much as possible.
The electrical team has been hard at work designing not one, but two electrical systems (one for the previous vehicle, one for MP-680). Their new system takes learned concepts and design ideas from the previous system and applies it to the new system. The team is adding many additional features to this year’s design with the intent of adding these features to both cars. One of these features is a driver heads-up display utilizing an Android smart phone with custom software to give real-time data feedback to the driver. They also plan to use an Arduino to collect and format data from the vehicles various external sensors and Engine Control Unit (ECU).
They are working with the engine team to get the Megasquirt ECU to control electronic fuel injection operating correctly, and will be able to begin testing once the air intake is finished. Their designs also include a Power Distribution System (PDS) based on a custom designed PCB board (shown on right) utilizing an Atmega32 microcontroller to handle appropriate power distribution to the entire electrical system.
These are the features that comprise the major parts of the system. They are all connected together with appropriate fusing, safety considerations, and shielding (to prevent inductive coupling). The major theme of this year’s electrical system is providing as much data to the driver in real time as possible, helping to both design an optimized driving strategy as well as modify said strategy mid-run as appropriate. The addition of an EFI system should vastly improve the fuel efficiency of the vehicle.
Tomorrow (Monday, September 10th) will be the first meeting for the SuperMileage Vehicle Team for the 2012-2013 year! The meeting will be held at 1:00PM (directly after the SAE Meeting) in S-341, which is the large lecture hall on the third floor of the science building (it is also the same location as the SAE meeting). Stop by to learn about the plans for the new car that we will be building, share your interests, and find out which aspect of the team interests you most. You will also learn about the competitions we compete at during the course of the year and how you can get involved in the team.
In addition to being an excellent learning project, the SuperMileage Vehicle project is a lot of fun. We go out for pizza, cook out, and become really good friends with each other through the process of building an incredibly efficient vehicle over the course of the year. We hope to see you all tomorrow as we look forward to a great year with SMV.
This past week, MSOE’s Supermileage Team was in Marshall, Michigan, competing in the 33rd annual SAE Supermileage competition. This is an event that MSOE has participated in for the past three years.
We began our trip early Wednesday morning (approximately 2am) when we departed campus on our 5 hour drive to Michigan. In comparison to our trip to Texas, this seemed to take no time at all. After a quick stop at Denny’s for some breakfast, we hurried off to a local park, our testing grounds for the day.
While there, we ran a few test runs and went through the entire rulebook multiple times, practicing all of the different procedures that would need to be tested during the technical inspection.
The next day consisted of technical inspection and test runs. We woke up early and got to the Eaton Proving Grounds and set up our garage quickly. We then got in line for Tech Inspection. We passed through the inspection with no problems, the first team to do so this year. We were then the first team on the track for test runs that afternoon. After attempting a few different driving strategies we retired for the evening.
Prior to actual runs being completed, each team guesses what fuel economy they will achieve. We estimated 843 mpg. When we got out to the track we made it our goal to finish as many runs as we could. In the end we attempted 9 total runs, 3 more than the next closest team. Six of these runs were completed successfully. The other three runs were stopped prematurely due to small electrical and mechanical problems that were easily fixed.
The first five successful runs achieved fuel economies of 812, 800, 796, 797 and 779 mpg. This is amazingly consistent considering our changing driving styles and drivers. We switched between runs that averaged 24 miles per hour to 16 miles per hour and switched back and forth between two drivers.
On our 9th and final run of the day, right before the track closed, we went back out in an attempt to beat the fuel economy of our first run. The car came into the fuel station as everything was getting packed up, and most teams had already returned to their garages. On our 9th and final run, we achieved a fuel economy of 841.9 miles per gallon.
In the 2012 SAE Supermileage Competition we took 6th place out of 30 registered teams with a fuel economy of 841.9 miles per gallon. We also won the award for being closest to the predicted fuel mileage, off by only 1.1 miles per gallon.
Overall, we determined that between a day of testing and a day of competing, our vehicle ran approximately 100 miles. In that time, based on our fuel economy, we burned no more than a 16 ounce water bottle’s worth of fuel.
It is our hope for next year to create a new vehicle, prepared for competition that will achieve at least 1000 miles per gallon.
I want to extend a great thanks to everyone who has supported us in the past few years. Without your support, it would have been impossible for us to achieve such an astounding feat. You can be sure to hear more from us this upcoming September when we will start the process over, in an attempt to once again obtain super mileage.
Five Guys Burgers (in Downtown Milwaukee) is offering a deal where MSOE’s Supermileage Team will receive 15% of proceeds from this upcoming Wednesday (during Supper hours) April 25. All you have to do is bring in the flyer below! Thank you for all of your support!