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Manche scheinen Zugriffsprobleme zu haben, darum hier der Text von Andrew Lindsay:
Features: Powerful drive and big grippy wheels, and a strong frame and good shock resistance. No active weapons, this robot batters its opponent with brute ramming and shoving force.
Design: This kind of robot lives or dies by its power, traction, and durability. Choose the largest drive motors - and batteries and motor controllers to handle them - and base your frame around them. You should have as a minimum 1 HP of total drive power per each 50 pounds of your robot's weight. More is always better - the strongest rammers have as much as 1HP per 10 pounds of total weight.
Choose a gear ratio and wheel size that gives your robot a top speed of no more than 20MPH - More than that will be uncontrollable. Low-end acceleration is very important - you should aim to have your robot reach its top speed in no more than 3 times its body length. Your robot's stall pushing force should be at least twice it's own weight, as it not only has to accelerate itself but also overcome the opponent's mass and drive power.
To get as much of that power to the ground as possible, you need large, high-traction wheels. Soft rubber pneumatic go-kart or wheelbarrow wheels are best, but be sure to get them foam-filled if you want your robot to survive. Solid-foam power wheelchair wheels have slightly less traction but more durability. Avoid plastic wheels, solid-rubber castor wheels, or metal wheels with thin rubber treads - these wheels not only lack traction, but their lack of compliance will make your robot bounce and skip when it hits bumps or debris.
Four or six wheels is better than two for a rammer. Four wheels gives much better stability than two, allowing you to line up a target and make dramatic cross-arena charges right into your target. Four wheels also makes it possible to get all of your robots weight reasting on its tire tread, where you want it, and allows you to put wheels all the way at the front and rear of your robot. This is important when fighting wedge or lifting robots. For a four wheeled rammer you should make the side to side spacing of the wheels at least as much as the front to back spacing - having the wheels farther apart front to back than side to side will make for slow turnign and an unmanueverable robot.
Your wheels should be large, with a diameter between a quarter and a third of your robot's length for a four wheeled design. Large wheels are more durable than smaller ones, with more material that needs to be damaged to make the wheel useless. Large wheels, protruding through the top of your robot's armor as much as the bottom, make your robot able to drive upside down as well as rightside up. You should also design in as much ground clearace, both on top and on bottom, to make your robot difficult to hang up on wedges, lifting arms, or debris. If possible make sure your robot can be tilted or have its front or back raised off the ground and have at least 2 wheels touching the ground.
Finally, a Ram needs to be able to take serious hits. Armor is important, but more than that your robot needs to have a strong frame and internal impact-proofing. Keep it clean and avoid unnesecary external details , and stick with a simple box with ramming points front and rear. Try and design to survive frame deformation - build your drive system so it is not dependant on your overall chassis alignment, leave generous clearance around moving parts, and leave a little slack in all your wires so that connectors don't pull free if a component shifts position. Heavy components like batteries and motors should be well secured.
Strategy: This design is best against rotary weapons - spinners, saws, and drums. With no fragile external mechanisms, a strong frame, and the ability to take solid hits, a Ram can keep hitting a spinner until the spinner self-destructs. This design is weakest against an opponent which can lift its drive wheels off the ground. A wheel and chassis design which lets the Ram still have two wheels on the ground even when one side is lifted will help this design get free from Wedges and Lifters, but being grabbed and lifted by a Clamp-Bot will render a Ram completely helpless. Use speed and lots of driving practice to keep that from happening to you.
First used: The Julie-Bot (Robot Wars 1994)
Examples: Hammerhead, JuggerBot, Ogre, Eraser
Features: A thin, wide, ground-scraping scoop on front, backed up by a strong frame and powerful drive system.
Design: Like the Ram, the Wedge's main weapon is its drive power, and the ability to hit and push its opponent. Rather than simply impact, the Wedge uses an inclined scoop front to lift the opponent on impact, breaking its contact with the ground and depriving it of traction. A well-made Wedge can keep the opponent from escaping while being pushed, by maintaining enough forward power to keep the scoop front under the opponent while shoving them across the arena.
Wedge design comes down to two things: enough power in the drivetrain and proper engineering of the scoop front. Power requirements of a Wedge are similar to those of the Ram - at least 1 HP per 50 pounds of robot weight, more if possible, and a drive gearing giving a top speed of 15-20 MPH and pushing power of twice the robot's weight or more. Wedges should be two or four wheeled - a two wheeled design will give faster turning rates, make the wedge more nimble, and allow a wide, short shape with maximum impact surface on the scoop, while a four-wheeled wedge will be more stable and drive in accurate straight lines. Six wheeled robots tend to be significantly longer than they are wide, which is not desirable for a Wedge - Wedges are better off wide and short.
The lower front edge of the Wedge is the most critical part of the robot. This part should be thin and sharp, so as to be able to get under low-built opponents, and as durable as possible as this lower edge will bear the brunt of full-speed impacts with the opponent, the arena walls, and any obstacles, arena hazards, or irregular spots in the floor which the Wedge runs into. If possible the lower edge of the front should be an integral part of the frame, rather than just an angled sheet of metal attacked to the frame and not supported at the lower edge. There have been many wedges disabled when their own wedge front got bent down, propping the front of the wedge off the ground and breaking it's wheels' contact with the ground.
The surface of the Wedge must also be strong enough to take the weight of the target robot being held on top of it. If insufficiently supported, the Wedge's front can be driven down into the ground, stopping it and preventing it from pushing the opponent further. Flexible materials should not be used for the leading edge of the Wedge, as these will drag badly on the ground once an opponent is on top of them. If a hinged flap is used for the wedge, it must be rigid and supported from underneath with structral standoffs which limit its movement so as to not be able to hit the ground.
As with the Ram the Wedge should be designed with maximum impact protection in mind, as it relies on collisions to disable its opponent. One tactic used sucessfully with Wedges is to make the entire outer shell, inclusing the front scoop, as a single shell of metal mounted through rubber bumpers to a seperate inner frame holding the drive system, batteries, and electronics. The drive frame is isolated from the impacts, and damage and deformation to the shell should not affect the inner drive system. The only drawback to this kind of design is that it makes the Wedge quite vulnerable to attacks from below, such as from other lower Wedges, Lifters, or floor-mounted arena hazards.
A variant of the Wedge is the Parralellogram-Wedge. Typically four wheeled, these Wedge types have a normal angled wedge on the front, an inverted wedge on the back, and large wheels which protrude through the top of the body shell. This design can run as well upside down as rightside up, using the rear wedge - which becomes the front when the robot in inverted.
Strategy: A well-armored Wedge is a good tactic to use against Spinners - if the front of the Wedge is strong enough to survive hits from the Spinner, it can be used to shove the Spinner into a wall or hazard, or even on a good hit to flip the Spinner completely over. A Wedge also has an edge when fighting a Ram, as with good power and good driving the Wegde can get under the Ram, denying the Ram the traction it needs to push back or get away.
Wedges are vulnerable to lower, faster, or more powerful Wedges, as well as Lifters and Clamp-Bots. A Wedge is helpless if its wheels are lifted off the ground, and the fact that most Wedges have ground-scraping armor and scoops means that anything which gets underneath them is very likely to do so. If possible design your Wedge to be able to run upside down, or to be able to quickly right itself if flipped over. Also give your wheels as much clearance as possible, and design your Wedge so that it still has traction even if the front or one side is lifted off the ground.
First used: Slow Moe (Robot Wars 1994)
Examples: La Machine, Punjar, Bad Attitude, Subject to Change without Reason
Features: An actuated arm, designed to hook under the opposing robot and lift it off the ground, flipping ot over or carrying it about.
Design: Like the Wedge, the Lifter is designed to get underneath the opposing robot and lift its drive wheels off the ground. The Lifter uses an active device to do so - an arm, driven by hydraulics, pneumatics, a geared electric motor, or an electric linear actuator - with enough power and leverage to tilt or lift up the other robot. The end of the arm is often wedge-shaped, or blended into a wedge-shaped front, and in many cases has grip-enhancing hooks or teeth.
The advantage of a Lifter over a Wedge is the ability to lift the other robot's wheels off the ground independantly of movement. While a Wedge can only lift the opponent higher by shovint itself under them, a Lifter once underneath the opponent can lift them up as high as its arm can go while remaining stationary. A well-designed Lifter can drag its opponent around the arena freely, while a Wedge can only push its opponent forward.
Most combat bots are designed to be very low and wide, and won't fall over until tilted 90 degrees or more. To flip opponents over with a Lifter, you will need an arm with a maximum height comparable to the width of your targets. Usually this means havcing the pivot point of the arm nearly at the back of the robot, and the arm extending on top of or down the middle of your bot to the front. Arms of this type can often double as self-righting mechanisms.
The most common drive systems for arms are linear drive actuators - either electric ballscrew types or pneumatic cylinders. Electric screw actuators, consisting of an electric motor driving a telescoping cylindrical assembly through a nut and screw mechanism, make for a slow but strong lift. These devices have the advantage of being contained and functional in one unit, needing only a radio-controlled relay or motor controller to extend and retract. Pneumatics are a faster and lighter weight option. A very powerful pneumatic system can actually hurl the opponent into the air - see the description under Launcher below. Pneumatic systems are more complex than electric linear actuators, having the added bits of tanks, regulators, valves, tubing, and optional buffer chambers, but in the end can make for a ligher weight and more flexible design. A pneumatic powered lifting arm also has the advantage of being unable to stop in mid-stroke (barring a complex position-controlled feedback system), which makes them less useful if your tactic is to drag the opponent around the arena rather than flipping them.
Hydraulics have also been used for lifting arms, but the complexity and weight of the hydraulic system make this an unnatractive option. Unless your robot already has a hydraulic system onboard for other reasons, an electric linear actuator will be much cheaper and lighter weight than a hydraulic lifter.
Shaft-driven arms, with the output of a gear or chain reduction directly driving the arm's rotation, are a more challenging design for a Lifter. Designing a motor drive capable of supplying, and surviving, the amound of torque needed to lift an opponent is difficult - most sucessful designs on this type use a large-diameter gear or sprocket bolted straight to the arm as the final drive stage, rather than attempting to drive straight through a shaft. The advantage of this king of arm is that the range of rotation possible is much greater than with a linear actuated arm - often enough to make the arm able to reach around behind the robot, reach down below it to push it off obstacles or lift while the robot is upside down, and even in some cases capable of full unrestrained 360 degree travel.
You must keep leverage in mind when designing a lifter. It does no good to have enough power to pick up an opponent, if your robot falls forwards on its front while doing so. Your advantage with a lifter is that you are usually not trying to get your opponent entierly off the ground, merely one side of them, so the down force on your arm will only be about half your opponent's weight. You should design to be able to lift the entire weight of your opponent, if not more so, in case of trying to lift a target with an unusually off-center CG. Having part of your robot's frame extend forward on the sides, or flat directly under the lifter, will give you the leverage you need to avoid tipping forward, but you should also consider the effect of that extra force pressing the front of your robot into the ground. The best Lifter designs have drive wheels as forward as possible, flanking the lifting arm, to take advantage of the extra traction possible from having part of an opponent's weight resting on them.
Strategy: The Lifter is strongest against opponents which rely on traction to fight - Wedges and Rammers. Robots with overhanging enclosed shells will be particuarily easy targets for a Lifter, as it can immobolize them by simply tilting one side up enough to lift their wheels off the ground. Sucess with a Lifter relies on being able to get the arm seated under an opponent firmly enough to lift, and it is against spinning robots that Lifters have their hardest time winning. Many Spinners have enough kinetic energy in their shell to knock the LIfter aside on contact, and unless the Lifter can somehow stop the Spinner's rotation it will simply take blow after blow until one robot breaks. Thwack-Bots are also very tough opponents, as their wild spinning and invertible, open-wheeled design make it very difficult for a Lifter to get into a position to take the Thwack-Bot's wheels off the ground.
First used: X-1 (Robot Wars 1994)
Examples: Biohazard, Hexadecimator, Gamma Raptor
Features:An actuated arm, powered by extremely high-flow-rate pneumatics, capable of launching the unlucky opposing robot high into the air.
Design: The Launcher is a specialized form of Lifter, with an arm capable of not just lifting but hurling their opponent into the air. This attack will not only flip the opponent over, but quite possible damage them from the impact, as well as make for an greato show for the audience.
A Lifter needs to release a tremendous amount of energy in a very short period of time to work. Electric motors, linear actuators, and hydraulics are too slow for this kind of mechanism. Most Launchers use specialized high-pressure pneumatics to get the impulse of force they need to fling the opponents, using modified hydraulic cylinders and high-pressure valves and hoses to run carbon dioxide or compressed air at 800PSI or more. This is not a system which can be built with off-the-shelf parts - sucessful high-pressure pneumatic launchers take years of research and engineering to develop.
Another option is to use lower-pressure pneumatics, and engineer for a very high-volume flow, with large-bore tubing and valves, and either a high-rate pressure regulator or a large buffer tank. While the engineering of the pneumatics is simpler, large-bore low-pressure penumatics will take up a lot more room in your robot.
A third option is to use a spring mechanism. A powerful torsion spring, or compression springs pushing the arm up, a powerful geared motor for reloading, and a latching mechanism to hold the arm down until remotely triggered. While avioding the difficulties of using pneumatics, this type of weapon is heavier than a pneumatic system, and the reload and latching mechanisms take some serious mechanical engineering skill to make. The time it will take to reload is also a significant disadvantage, as until the arm is down your robot will be helpless against the opponent. A single-shot launcher design which cannot be reloaded should not even be considered.
Whichever mechanism you use to power a launcher, your frame and drive system is going to be subjected to a tremendous jolt every time it fires its weapon. Your frame must provide a strong structural path between the launching mechanism and the drive wheels, as the arm is going to impart a massive downward force on the frame every time it fires. The entire robot should be built with major jolts in mind - be careful that nothing can shake loose and all electrical components and connectors are solid.
Finally, this kind of robot can be very dangerous to build and test. The forces involved in flipping several hundred pounds of robot through the air can kill you if the weapon mis-fires with part of your body in the path of the flipping mechanism. Be careful. Most competitions will require you to have some way of locking the mechanism when not in combat, usually with a pin or rod passing through a hole in the frame which prevents the arm from moving.
Strategy: Like the Lifter, the Launcher works best against wedges and rams. It can also make a great weapon against slower Lifters - even if the Lifter can self-right, being hurled repeatedly into the air and slammed against the ground can eventually break it. Using a Launcher against a Spinner is tricky - while most Spinners will be broken or disabled by being flung into the air, getting a firm hit on the Spinner with the flipper arm takes skilled driving, and surviving the hit takes a solidly built flipper arm. As with Lifters, a Thwack-Bot is a very difficult opponent - the Launcher will have difficulty getting in a position to flip, and most Thwack-Bots can run just as well upside down.
First used: Chaos II (Robot Wars UK 1998)
Examples: Toro, T-Minus
Features: An actuated lifting arm, with an additional moveable piece to act as a grabbing clamp, capable of grasping the opposing robot and lifting it completely off the ground.
Design: The Clamp-Bot takes the strategy of the Lifter one step further, addind a second moveable piece to the lifting arm to act as a clamp to solidly grasp the opponent robot. A well-balanced Clamp-bot has the ability to completely lift the opposing robot off the ground. As very few robots can do anything when lifted off the ground, this places the match completely in the control of the clamp-bot.
The clamping mechanism must open wide enough to grasp the largest opponent you are likely to face, and should be designed to close in a second or less. A slower clamp risks the opponent getting free before the clamp is able to close. The grabbing mechansim should have a holding force at the tip at least equal to the target robot's weight, to prevent the claw from being forced open when the arm lifts. Pneumatics are a good choice for the closing mechanism, as they can provide both high speed of closing and strong clamping force. Electric linear actuators or hydraulics will also work, providing superior closing force to pneumatics at the cost of a slower closing speed. Attaching the closing arm directly to the output shaft of a gearmotor is another possibility, although not recommended as it will not be as durable as driving the arm with a linear actuator.
Leverage is the key to a succesfull clamp-bot. In most cases you will be attempting to lift a target which weighs as much as your own robot. While a Lifter usually only has to lift up one side of its opponent, a Clamp-Bot has to bear the entire weight of its opponent on the end of its arm. To avoid falling forward while lifting its opponent, the Clamp-Bot will need frame extensions on either side of its arm extending forward as far as possible. Having a center of gravity as far back as possible will also help avoid tipping forward.
To be successful a Clamp-bot must not only be able to grab and lift its opponent, but carry them around the arena. This means having a drivetrain strong enough to carry twice the Clamp-Bot's own weight, and the front end of the Clamp-Bot's frame must be designed to ride smoothly on the ground. Ideally a Clamp-Bot would have drive wheels forward straddling the lifting fork, so that the opponent's weight is directly born by the driving wheels. A Clamp-Bot must also have the speed to catch fast opponents.
The need for a strong, well-balanced frame, a drive system having both great carrying power and high speed, and seperately driven mechanism for grabbing and lifting, make Clamp-Bots one of the more challenging robot types to attempt.
Strategy:Clamp-Bots work well against Rams and Wedges - these types of robots completely dependand on their drive power for weapons, and once grabbed and lifted are completely helpless. Against a Thwack-Bot the challenge for a Clamp-Bot will be in catching its opponent - many Thwack-Bots are fast enough to make catching and grabbing them very difficult. LIke the Ram and Wedge, firmly grasping ald lifting a Thwack-Bot leaves it completely helpless.
Spinners, particulary completely enclosed shell-type spinners, are a tough opponent for a Champ-Bot. The spinner's weapon must be stopped before the Clamp-Bot can grab it, but the only way the Clamp-Bot has of stopping the shell is by repeatedly ramming it, taking punishing blows to the arm mechanism before the spinner is slow enough to be grabbed. With more working parts and typically ligher frames, Clamp-Bots are more likely than most robot types to be damaged by this kind of punishment. A vertical spinner or drum type robot is an easier target, if the Clamp-Bot can outbanuever it and grasp it without taking a hit.
Finally, care must be taken when grabbing Hammer wielding robots with a Clamp-Bot, as a firm grasp can also give the Hammer-Bot the leverage to hit the Clamp-Bot quite hard in the same spot repeatedly. When attacking a Hammer bot with a Clamp-Bot, try to approach from the side so as not to be in the path of the hammer arm.
First used: Namreko 3000 (Robot Wars 1996)
Examples: Complete Control, Tripulta Raptor, Spike IV, Mantis
Features: Powerful two-wheeled base, with a long tail boom having an axe, pick, or hammer head on the end, capable of spinning in place at high speed.
Design: Another design which uses only its drive motors for attack power, the Thwack-Bot spins rapidly in place, whipping a weapon on a long tail about at high speed. Thwack-bots are invariably two-wheeled, as four or six wheeled designs cannot spin in place rapidly enough to make for a satisfying impact. Usually this design exposed wheels, and a symmetrical profile which allows them to run perectly well inverted, making them a difficult opponent for wedges or lifters.
Narrow wheels are key to a Thwack-bot, as wide wheels will add scrub resistance and slow down the turning rate. Care must be taken to balance the robot so that as much of the weight as possible is resting on the main drive wheels - any weight resting on the tail or on any idler wheels is potential traction going to waste. The wheels should be soft rubber, high traction types, and foam filled for survivability. Placing the wheels closer together increases the top speed but will increase the time it takes to reach that top speed.
The main design challenge with Thwack-bots is finding a balance between top speed and spin-up time. Idealla a Thwack-bot should be able to reach top rotation speed in less than a single revolution, yet still have a top speed fast enough to do damage on impact. A Thwack-bot which takes too long to spin up will find itself helpless once an opponent has come to clone range and suvived one hit. Of course, more power makes for faster spin up time and higher top speed, so a Thwack-Bot should have as much power as possible.
The primary weakness of the Thwack-Bot concept is that it cannot move while spinning. This type of robot must either spin in place and hope its opponent drives into it, or charge to within spin radius and then spin - getting less than a full revolution before striking its opponent. There have been several attempts to build a navigation system which allows a Thwack-Bot to translate while spinning, by periodically varying the drive power in sync with the rotation - causing a slow wobble towards its opponent while spinning at nearly full speed. So far this system - popularly known as "Melty Brain" control - has proven to be a suprisingly difficult engineering challenge.
Strategy: A powerful Thwack-Bot has proven to be an effective tactic against the Lifter - a strong spinning attack can keep the Lifter from getting its arm in a position to pick the Thwack-Bot up, and the open-wheeled design and powerful drive of most Thwack-Bots makes them difficult to keep a grip on. A Clamp-Bot which gets a firm grasp on a Thwack-Bot will render it helpless, but a powerful Thwack-Bot can make it very difficult and dangerous to get such a grasp. Wedges are difficult to fight with a Thwack-Bot, with the victory often coming down to speed and manueverability.
Drums and Vertical Spinners can also be very dangerous customers for a Thwack-Bot to fight, as the long weapon boom of a Thwack-Bot can get hit and tossed upwards violently, disrupting the Thwack-Bot's spin as its wheels loose contact with the ground from the impact. The spinning, low-mobility attack of the Thwack-Bot makes it impossible for it to choose its angle of attack, letting its opponent line up the hit as it likes. A secondary attack mode of ramming and pushing can help in those cases.
First used: The Scorpion (Robot Wars 1995)
Examples: Spaz, Blade Runner, T-Rex
Features: Wide two-wheeled base, with the main body being built entierly between the two wheels and fitting into their radius, and a long weapon-tipped boom such that the body flips over and brings the weapon down on the opponent whenever the robot reverses direction rapidly.
Design: Like the Thwackbot, the Overhead-Thwackbot uses its motor torque to power an impact weapon. Unlike the conventional Thwackbot, the Overhead-Thwachbot attacks by reversing its drive power rapidly, the reaction torque from the drive motors swinging the entire body end-over-end and bringing the tail end down in front of it violently.
The challenge comes in getting enough inertia into the body of the robot to hit with significant force and sufficient accuracy to hit the target. The same rapid reversal of drive power that brings the weapon over will also drive the robot away from the target - attacking with a overhead-thwackbot is accomplished by charging at a target then slamming into reverse just before impact. The entire robot has to be balanced just right, such that the robot flips over quickly before it starts to back up significantly. Insufficient or unever wheel traction can cause the robot to veer to one side while flipping, causing the weapon to miss its intended target. Widely set wheels will help with accuracy.
While a conventional Thwackbot can take several revolutions to get up to speed, an overhead-thwackbot must produce all its weapon power in less than one half of a full revolution of its drive wheels. The electrical and mechanical drive power components have to be optimized for a very high rate of energy delivery - high current rate batteries, thick wiring, high-horsepower motors, and very rugged drive gearing are a must. All the main components have to be fit between the drive wheels for the robot to flip freely. Usually these bots have large diameter wheels, set wide apart, to get sufficient room between them for the main body. Of course, large diameter wheels usually means a high gear reduction to get the right speed and torque, and large wheels and a high gear reduction will make the wheels respond more slowly to rapid motor power reversal.
Strategy: The Overhead-Thwackbot is a difficult design to make work sucessfully. The prime advantage of this design is its inability to be disabled by being flipped over. LIfters and wedges have a hard time getting a grip of this highly mobile design. Hovever, even the best Overhead-Thwackbots lack sufficient power to strike a killing blow, instead having to hit repeately and hope to win by judge decision.
The most successful Overhead-Thwackbot designs have been those which combined the conventional overhead hammer with a freely swinging wedge. The wedge itself must pivot on the axis of the wheels, a tricky mechanical bit to pull off, but can allow the Overhead-Thwackbot to push an opponent around the arena, or pin them in place before reversing to strike with the weapon.
First used: Spirit of Frank (Robot Wars 1995)
Examples: ToeCrusher, OverKill, Mjollnir
Features: Robot having a heavy spinning bar or disk, possible with hammer heads, chisels, maces, or other weaponed pieces attached.
Design: The Spinner uses the concept of a flywheel, storying the mechanical energy output of a motor in a spinning mass, to be released in one massive blow to the opposing robot. The Spinner was one of the first sucessful tactics for inflicting actual damage on the opposing robot; it remains one of the most dangerous not only to the target robot but also to the weilding robot, the arena, and the audience. Nearly all incidents of penetrated arena walls and injured audience members have been due to spinners with more energy than the arena could safely contain.
The earliest spinners were bar-shaped, often with hammers or spiked balls on chain attached to the ends. While simple to build and lightweight, these designs don't store as much energy as disk or ringed shaped spinning weapons. Thin bar or tube spinners are also more susceptible to bending or breaking on impact. The ultimate form of the spinner is to completely enclose the robot in a spinning cone, dome, or cylinder shaped outer shell. With this type of design, it will be impossible for an opponent to hit the Spinner without being struck by the Spinner's weapon.
The advantage of spinners is to allow the energy output of a motor to be stored over some time in a kinetic form, ready to be delivered into a target in a moment. This does not mean that you should use a small motor - the faster your spinner can get up to speed, the better your robot will fare against a determined and durable opponent. A spinner which takes more than 10 seconds to spin up may never get the opportunity to reach top speed - you should aim for a spin-up time of 3 seconds or less.
While a powerful spinner is the most destructive form of kinetic energy weapon in the competition, this destructiveness comes with a price. The powerful kinetic impacts which the Spinner delivers are felt as much by it as by the opponent; many Spinners have crippled the opposing robot only to be themselves knocked out by the same impact. A Spinner needs to be built as ruggedly as possible to avoid this fate. Many of the fully enclosed shell type spinners use rings of rollers on the inner frame to allow the spinner to ride smoothly even if it becomes bent or dented.
A fully enclosed spinner has an additional difficulty not faced by other bots: when the weapon is running, it can be difficult for the bot's drive to see which way the base inside is facing! Methods of dealing with this include having a tail trailing out underneath the shell, having a non-rotaing flag or arrow sticking up through the center of the shell, making part of the spinning shell out of transparent materials, or cutting windows in the shell to allow the interior to be partially visible.
The reaction torque of spinning the shell will produce a strong turning force on the base of the robot, which will make the bot want to curve to the side when driving. A four wheeled base is recommended, to give some straight-line stability. Many Spinner drivers also use RC helocopter rate gyroscopes in their control electronics to compensate for the effects.
Strategy: Ideally, a Spinner wants to knock out its opponent in as few hits as possible. A spinner's worst possible opponent is a solidly built Ram or Wedge, which can take repeated impacts until the Spinner breaks itself. A high-speed collision with a Wedge can cause some spinners to flip themselves clean over. Spinners fare better against Lifters, Clamp-Bots, or Hammers - exposed weapon parts that ban be bent or broken off help a Spinner win.
First used: The South Bay Mauler (Robot Wars 1994)
Examples: Hazard, Odin, Ziggo, Tortise, Turbo, Blendo
Features: An abrasive or toothed disk, spun by a powerful motor, intended to cut or rip the opponent on contact.
Design: Now increasingly rare, the Saw was tried many times in the early days of robot combat, usually with little success. The idea of disabling the opponent by slicing them apart has proven to be a difficult challenge, as the materials most modern combat robots are made of take too much time to cut even under controlled circumstances, let alone when the target is actively trying to get away from the saw blade. The concept has been largely abandoned, aside from a few brave robots which use saws in combination with other attack styles.
Combat trials have shown that the best saw blades to use are the emergency rescue blades used to rescue accident and building collapse victims. Thick steel disks coated around the edge with hard abrasive, these blades are made to quickly cut a wide variety of metallicd non-metalic material quickly - just the thing for a combat situation. They are however heavy, expensive, and available only through certain specialty dealers, and require a sriously powerful motor to be used to full effect.
Other types of saw blades have not proven to be effective. Abrasive disks are nearly useless against soft materials like plastics, wood, or composites, and easily shatter on impact. Toothed wood-cutting blades cut softer material nicely, but stall on metals. Milling saws are very heavy, can shatter on hard impacts, and usually knock the opponent away rather than cutting into it.
Strategy: The Saw, by itself, is not an effective means of disabling an opponent. Unless already disabled your target will not stand still and give you the time to cut into it, so the most a Saw is likely to do is leave scratches and shallow cuts while throwing sparks and dust. While rarely fatal to the opponent, a powerful saw and the cosmetic damage it leaves can impress the audience and judges enough to give you the win in a close match.
Saws are best combined with an attack strategy which gives you the dominance over the opponent's mobility - a powerful Wedge, Ram, or even a Lifter or Clamp-Bot can prevent the opponent from dominating the match, and give the Saw weapon time to score points by inflicting visible damage. Against a Spinner a Saw may be worth than useless however - the exposed saw blade is usually the first thing to break when struck by a serious weapon.
First used: The Master (Robot Wars 1994)
Examples: Ankle Biter, Chiabot
10. Vertical spinner
Features: A heavy disk or bar, spinning on a horizontal axis on the front of the robot. Usually spinning such that the front of the spinner is moving upwards, so that on contact the opponent not only recieves a massive blow but is lifted into the air from the impact.
Design: The Vertical spinner takes the basic spinner concept and turns it on its side. Instead of having a spinning blade or shell on top of the robot, the Vertical Spinner sets the mass spinning about a horizontal axis, almost always with the exposed front of the spinner moving upwards. When it strikes an opponent the impact force pushes the opposing robot upwards, often flipping them over or subjecting them to a hard impact with the floor when they land. The recoil force on the Vertical Spinner merely pushes it down against the floor, rather than flinging it sidewars as can happen with a conventional spinner.
While the weapon can be much more effective than a standarad horizontal spinner, the Vertical Spinner trades off improved offense with a much weakened defense. While a standard spinner can be built to completely cover the robot's body, such that an opponent cannot help but to be hit by the weapon on any contact, the Vertical Spinner's narrow disk must be carefully lined up on its target. The large disk gives the Vertical Spinner a dangerously high center of gravity, requiring a large, wide body to support it - which makes the Vartical Spinner vulnerable to attacks from the sides or rear. When spinning the disk will generate significant gyroscopic effects every time the robot turns, requiring widely set drive wheels and a slow turn speed to avoid the robot actually flipping itself over when turning. The Vertical spinner also suffers the same self-inflicted impacts as the standard spinners. While the impacts are downwards and the floor helps brace the robot in place, there have been matches in which Vertical Spinners have been destroyed by their own weapon impacts.
Strategy: Vertical spinners are good against anthing which cannot disable them quickly our outmanuever them to avoid being struk by their weapon. A slowly moving lifter, clampbot, or rammer will be an easy target for a Vertical Spinner. A Wedge may be a tricky target for a Vertical Spinner, especially if cone or pyramid shaped, as the spinner blade works best when it can catch on an edge on the target robot. A fast moving wedge or lifter that outmanuevers a Vertical Spinner can be a very difficult opponent.
A fight between a Vertical and a Horizontal spinner is usually short and violent, and can go either way. If the Vertical Spinner manages to bring its weapon into contact with the Horizontal Spinner's body, the resulting impact can damage Horizontal Spinner's mechanism and disable it or even in extreme cases flip the Horizontal Spinner over. The Vertical Spinner can also take significant damage from the hit, and if the Horizontal Spinner is able to manuever to strike at the Vertical Spinner's exposed drive wheels it stands a chance of ripping them clean off and winning the firght without taking any direct hits.
First used: Nightmare (BattleBots 1999)
Examples: Backlash, Nightmare, Greenspan, Garm
Features: A wide drum, with protruding teeth or blades, mounted on an horizontal axis across the front of the robot, spinning at high speed. Like the vertical spinner, these usually have the front of the drup spinning upwards to lift the opponent on contact.
Design: Similar to the Vertical Spinner, but instead of a narrow disk or bar weapon the Drum uses a horizontal cylinder, usually covering the entire front of the robot, studded with teeth and spinning with the front travelling upwards. While the Drum shape carries a lot less rotational interia than a wider disk, the design makes up for it with improved durability and a more compact shape.
Less inertia in the rotor makes for weaker impacts, but it also makes for faster spin-up time and less impact force felt by the rest of the robot. Drum robots can typically hit an opponent repeatedly in a short period of time, and with a lower center of gravity and less gyroscopic effect to fight can be faster and much more nimble than a Vertical Spinner. Drum designs are also much more amenable to being designed to run upside down - usually accimplished by making the drum diameter just less than the wheel diameter, and using a reversable motor to spin the drum, so that the weapon can operate equally well either right-side-up or upside down.
Drum robots are typically made in a 4-wheeled configuration, with a roughly square overall shape. The wider weapon doesn't need much careful aiming to use effectively, and as the impacts of the weapon tend to lift the target robot into the air the Drum functions well in a ramming/pushing mode - repeatedly kicking its opponent across the arena with a combination of weapon hits and drive power.
The vulnerable part of the drum is the drive mechanism and support structure. The simplest and commonest design is to support the drum with bearing blocks on either side, and use a chain drive to run the Drum from a motor inside the main body of the bot. This method works until a strong blow to either front corner breaks a support arm, cracks a bearing block, or dislocates the chain. Hiding the drive motor inside the drum is a more durable but much trickier option.
The Drum will be subjected to a major downward impact every time it strikes an opponent, so suport arms or wheels under the Drum weapon to keep it from being driven into the arena floor is a good idea. Many Drums also have some kind of ramp or scoop built into the drum supports, so that Wedges will be fed up into the Drum rather than getting under it without being hit.
Strategy: Drums led themselves to an agressive driving style, the fast weapon spin-up and ability to upset an opponent's footing on a good hit mean this style of robot can take control of the match and keep the opponent on the defensive. Robots that don't do much damage quickly or need time to set up a controlling move - such as Thwackbots or Lifters - can usually be beaten by a good Drum.
The bane of the Drum is the Wedge. A Wedge's sloped front - and often sloped sides as well - don't offer a good surface for the Drum's weapon to catch on. A well-designed, powerful Wedge will have more of its weight budget devoted to drive power that the Drum and if the Drum's weapon cannot catch on the Wedge to damage and flip it up, the Wedge will have the advantage.
In a fight between a Dum and a Spinner, the battle usually will hinge on whether the Drum's weapon drive and support structure can hold together long enough for the Spinner to be disabled. The Drum's weapon can kick a Spinner into the air, brekaing its traction and spinning it around under the recoil of it's own weapon, but the drum weapon is going to take a significant impact from the force, possibly disabling it or even tearing it free from its mounts.
First used: Gut Rip (Robot Wars 1996)
Examples: Little Drummer Boy, El Diablo
Features: Hammer, axe, pick, or mace weapon on powered overhead arm, designed to inflict repeated blows on an opponent's top armor.
Design: Like a Spinner, a Hammer bot accelerates an impact weapon, storing kinetic energy which is all released into the opponent in an instant. While the Spinner can take its time storing energy in its weapon, the Hammer design must get its weapon up to speed in a single swing, dumping its energy into the weapon in less than a second. This idsadvantage is offset by the Hamer's ability to control the timing and placing of its hits, strike repeatedly in a short period of time, and use its weapon even if pinned or lifted. Most Hammer weapons can also be used a self-righting mechanisms if the Hammer bot is flipped.
Most Hammer weapons are pneumatically driven. The commonest and easiest method is to attach a pneumatic cylinder which pushes the hammer down from behind. This limits the hammer's travel to at most 90 degrees, less that if you are striking a tall robot. This isn't much room to get the hammer up to full speed, and will mean that your weapon will only strike very flat robots with its full power. A better option is to use a mechanism which allows the hammer to travel a full 180 degrees, permitting it to get up to full speed before it impacts. This can be accomplished with a pneumatically driven rack-and-pinion mechanism driving the hammer arm, or using a pneumatic cylinder to pull a chain wrapped around a sprocket connected to the hammer arm.
Whichever mechanism is used, the limiting factor in your pneumatic hammer's speed will be the rate at which you can make the working gas flow from your storage tank into your driving cylinder. As the pressure regulator is a major bottleneck, some pneumatic hammer-bots have huge low-pressure resivours downstream of the regulator to provide the high flow rates which the hammer needs. Other bots use massively large-bore tubing and valves to minimize flow resistance in the pneumatic lines. High pressure systems which run gas straight out of a carbon dioxide tank with no pressure regulation can provide extremely high rates of force delivery, but are expensive, dangerous, and difficult to build. Carbon dioxide absorbs a lot of heat from its environment as it expands from liquid to gas, which means that a CO2 tank called upon to provide gas for many hammer shots in a short period of time can freeze up and become too cold to deliver gas quickly enough to keep the weapon running. To get around this some builders use high pressure air stored in scuba tanks at up to 3000PSI. This gets around the problem of the tanks freezing up, but doesn't store nearly as much energy in the same space, requiring huge tanks to run a hammer for an entire match.
Another option is to drive the hammer with an electric motor. This makes it easy to give the weapon 180 degrees - or more - of travel, allowing it to reach full speed before hitting the target. Gearing should be optomized for maximum speed at impact - taking into account that with too low a gear ratio, the motor won't have enough torque to get up to speed, while too high a ratio will mean that your hammer will reach its top speed too early and not do as much dammage as it should. Problems of both speed and torque can be solved by choosing the most powerful drive motor you can for the mechanism.
Some hammer robots have used a crankshaft mechansim, to produce reciprocating hammer motion from a continously turning drive motor. When considering this kind of mechanism, you should keep in mind two things. Firstly, you want the hammer moving at maximum speed when it strikes the opponent - many simple crankshaft mechanisms will have the hammer only travelling at top speed in the middle of the stroke. Second, if the hammer's motion is interuppted mid-stroke, it should have some way of reversing and striking again without stalling or having to lift the entire robot off the ground.
Hydraulic powered hammers have also been built. Hydraulics can provide tremendous force, which can accelerate a hammer very quickly, but the slow speed of most hydraulic systems are not ideal for the high top speeds and rapid-fire striking a good hammer should have. Building a sucessful hammer mechanism with a hydraulic drive will require a very powerful motor and expensive, high flow rate valving and tubing.
Some builders have experimented with using a large spring to power the hammer, and a high-torque motor or linear actuator to crank the hammer back and latch it after firing. While this can give a very powerful hammer action, the increased reload time makes the concept questionable. A hammer that takes more than 5 seconds between shots may never manage to hit its opponent more than once or twice in an entire match.
Strategy: Even the strongest Hammer-Bots have trouble consistently disabling opponents with their hammers. A Hammer-Bot's best opponent is one with weak top armor or a fragile frame. Barring that, a Hammer-Bot should try and strike as many blows on the opponent as possible while avoiding being disabled. A Hammer stands a good chance against a Thwack-Bot., Wedge, Ram, or saw-wielding robot, as those designs won't be able to disable the Hammer quickly and the Hammer can get a lot of good hits in. Against a Crusher, a Hammer bot will have a very hard time; the Hammer may need to strike many blows to affect the Crusher, but the Crusher only needs to get lucky once.
Any good Hammer-bot should be able to very quickly self-right with its weapon, which reduces the threat from LIfters and Launchers. Fighting a Spinner with a Hammer is often disasterous for the Hammer - the Spinner's weapon will be nearly impossible for the Hammer arm to avoid, and striking the active Spinner with the hammer arm will likely result in a bent or even torn off weapon!
First used: Thor (Robot Wars 1995)
Examples: The Judge, Killerhurtz, Frenzy, DeadBlow
Features: A large, heavily reinforced claw, usually hydraulicly powered and capable of closing with several tons of force to crush or pierce the opposing robot.
Design: Mechanically the most challening concept to build, Crushers uses powerful claws to pierce and crush the opponent. Most Crusher designs use hydraulics to achieve the incredibly high forces needed to pierce armor, although ballscrew linear actuator designs have also been used.
The challenge of a Crusher design lies not only in achieving the force required, but in designing a claw structure strong enough to deliver the force without collapsing. Most crusher designs use claws which taper to narrow blades or spikes to focus the force on as small an area of the target's structure as possible. The claw needs to be designed to not only survive its own crushing force, but rigid enough to avoid bending on hits from spinners, or off-center forces from closing onto a sloped surface.
Ideally, a crusher's claw should be large enough to fit a sizeable chunk of the opposing robot into. A claw that's too small will not be able to damage much more than outer armor layers or small protruding pieces, and if used against a large target with curved surfaces might simply slide off the target without digging in. Typically you will want your claw to open as large as the height of the largest robot you expect to fight, and be long enough to get at least a thrid of the way into your opponent for maximum damage potential.
You also want the claw to close as quickly as possible. A claw with takes more than a few seconds to close will likely allow the opposing robot to escape before being crushed. A closing time of one second or less should prevent even an agile robot with high cround clearance from getting free. Of course, the combinantion of high force and high speed requires a very powerful motor to drive the claw mechanism. A variable-displacement pump on a hydraulic powered crusher will allow you to do both with less power - the hydraulic system can run in high-speed low-pressure mode until the claw makes first contact, then switch to high-pressure mode for the main crushing action.
A well-executed crusher is one of the few designs with the potential to significant internal damage to its opponent. While a powerful spinner might break up a robot's frame and rip off external parts, a Crusher that hits the right spot can punch holes through radio gear, batteries, or other electronic parts, decisively disabling its opponent. A Crusher also has the advantage that, once its claw has grasped an opponent, that opponent will find it impossible to escape. A Crusher with a high-torque drive system can grasp, then drag its opponent into arena hazards, or pin them against a wall before opening its claw and taking a second bite.
Strategy: The crusher mechanism will invariably take up a large part of the robot's weight, leaving little left over for armor and drive system. While they may only need to score one hit with their weapon, a Crusher bot may be at a disadvantage when faced with a faster, more agile opponent - especially a Wedge or Lifter that might get to the Crusher from the side and flip it over. Thwackbots typically have high mobility and good ground clearance, and may be able to flip themselves free of the crusher before it closes. The easiest target for a Crusher is a robot which doesn't have a method of taking control of the match or dealing a killing blow quickly - weaker Rams and Hammer-bots are easy Crusher prey.
A good Spinner will be a challenging opponent for a Crusher. While most Spinners do not have very strong drive systems, a Spinner with a powerful weapon may be able to keep a Crusher from ever getting in position to use its weapon by knocking it aside on every impact. Against Spinner, the Crusher bot's best bet is to try and first knock the Spinner into a wall to stop its weapon, then rush in for a killing grab before the Spinner can recover.
First used: Munch (Robot Wars 1996)
Examples: World Peace, Razer, Jaws of Death, Fang
> First used: Chaos II (Robot Wars UK 1998)
ACtually, First was Recyclopse in RWUK97, then Cassius & Chaos in 98, and then Chaos2 & Cassius2 in 1999. All 5 were built in the workshop of Rex Garrod (and I am hearing he's planning on bringing Cassius 3 to the next BattleBots)
You need to hit Pneumatic spikes, which, while ineffective, seem to be the first thing anyone wants to do.
Then there are true exotics that are hard to classify, like Mechadon.
And maybe do a short write up on why the illegal weapons are illegal.
(Could use a little proofreading too).
Gibt es den Text auch in Deutsch
Sofort nachdem ihn jemand (du?) übersetzt hat...
Ich mach mich schon an die Arbeit
"Gibt es den Text auch in Deutsch"
Wieso??? Das war doch noch nicht mal" business-english"!
Hey Scotchko, vielen Dank für den Text.
So langsam sehe ich klarer über die notwendigen Fähigkeiten, die "mein Kämpfer" mitbringen soll...
Eine gute übersicht... Ich bin für ein Mittelding aus Crusher und Ram..
lifter und saw wär au maln versuch wert:kettensaege::bounce:
Absolut profimässige Typenbeschreibungen and I really enjoyed your Website as well. I'm very new in this game of robots but I think I've dreamt up a good combination design. My observations thus far match exactly with your expert run down. One thing I haven't seen yet is a drivingspike maybe with sawteeth that works on the same principles of a motor driveshaft, of course with the right counterweight(s)and ball-bearing anchorpoints driven with a very quick motor working like a jigsaw. I know the downside as well - Thwackbots or Spinners could break it off, but a person doesn't have to build it in such a vulnerable area or have to go rushing in against these kind of enemies. On the other hand it would be very satisfying to slice open a wedge or say slice up the treads of a tread vehicle with it.
I'd like to combine the advantages of a wedge with those of a strong Thwackbot offering as little attack surface as possible, of course the importance of the robot's ability to right itself is not lost on me either.
I wish you luck with your new Killer Maschine
sorry to disappoint you, but the rightful copyright holder of that article is not me, but Andrew Lindsay, who is writing a book on Robot Wars, and who has put up this excerpt for preview.
Anyway - have luck with your design.