Before they started building, Strickland showed them a pumpkin-chunkin' video for inspiration. To earn a good grade, all parts on the catapults and trebuchets had to work properly. Pacey Beck used a mouse trap as a key element to get more power behind the lever's snap in order to throw the projectile further. Dajiah Moore's catapult incorporated a gate lock and blue bungee cords. Blaine Elmore built his catapult out of black pencils and yellow electrical tape. In a first for the class, Lacie Harvill built her catapult using a 3-D printer at her dad's office to create the parts.
Overall, females held their own with men, often imbuing the designs with curb appeal. Destiny Johnson built her miniature out of Popsicle sticks sparkling with blue glitter. And one can only imagine the mixture of terror and parental pride Michael Tudor's parents felt when he transformed a red steel sled into a catapult so powerful, when the lever flew forward it slammed into a steel restraining bar -- and broke it in half.
Students found their designs online or in history books but were always tweaking them with improvements. Many students painted their agents of destruction in Central's colors, purple and gold. Azibar Bareither Pundit. Why was the catapult invented? During the Middle Ages, many weapons were created to help aid in the winning of battles. As the castle walls became higher and stronger, a new way had to be invented to destroy them.
One such weapon was the siege engine called a catapult. The first catapult however was invented around BC in Greek town Syracus. Gino Dippold Teacher.
When was the last time a catapult was used in battle? The last time a trebuchet was used in professional warfare was in with the forces of Hernan Cortes.
In the Battle of Tenochtitlan, Cortes employed trebuchets due to the critically limited supply of gunpowder that was available to the Conquistadors. Krastina Bernecker Teacher. What is the difference between a trebuchet and a Mangonel? The mangonel did not have the accuracy or range of a trebuchet and threw projectiles on a lower trajectory than the trebuchet. The mangonel was a single-arm torsion catapult that held the projectile in a sling.
Tandra Porron Teacher. What is the difference between a trebuchet and a catapult? Mervin Torea Teacher. What is a catapult for kids? A catapult is a type of machine used as a weapon to throw rocks or other things such as hot tar, that would cause damage to something else. Often, catapults were set on higher ground or on castle towers to let them shoot farther. They shot rocks to break castle walls, or pitch or hot tar to set the target on fire. Mariely Hollnagel Reviewer.
Why was the catapult important? Catapult , mechanism for forcefully propelling stones, spears, or other projectiles, in use mainly as a military weapon since ancient times. The ancient Greeks and Romans used a heavy crossbowlike weapon known as a ballista to shoot arrows and darts as well as stones at enemy soldiers. Kwabena Pfefferling Reviewer. How does a catapult get its energy?
The catapult works when the potential energy stored in a stretched rubber band is converted to kinetic energy when it snaps back to its loose shape, moving the catapult arm—and the projectile! After students build their catapults , they will test them by launching projectiles. Selenia Cantarini Reviewer.
What type of catapult launches the farthest? The mortises for the lower tenons of the three sloping supports which prevent the two uprights, and their crossbar, from giving way under the blow of the released arm of the catapult, figures and The upper ends of the two side supports are mortised into the tops of the uprights, to which they are also bolted, figure and The top of the middle support is mortised into the center of the cross-bar that connects the uprights, figure and figure Catapult Experiments and Testing.
The ends of the rope are passed through holes in the winding roller and are then secured by knots, F , F , figure The upper part or bend of the rope is hitched by a slip hook to a ring bolt which passes through the arm of the catapult. The position of the catapult arm when it is fully wound down by the roller. The stone may be seen in the cup of the arm. By pulling the cord E , the catapult arm is released from the slip hook and , taking an upward sweep of 90 degrees see curved line of arrows , returns to its original position, as at A.
The position of the arm of the catapult at the moment when the stone leaves it. The stone is projected upwards at an angle of about 45 degrees, as represented by the straight line of small arrows that indicates its flight after it leaves the arm at C.
When the arm reaches the point in its upward sweep at which its speed is greatest, the stone instantly flies away in front of it. That is to say, when the catapult arm decreases in speed, however slightly, it cannot keep pace with the stone it projected the moment it reached its maximum velocity.
This principle should apply equally to the bow and its arrow. In this case I believe the arrow leaves the bowstring before the latter has returned to its position of rest, or as it was before it was pulled back by the archer to discharge the arrow.
When I originally directed my attention to building a catapult I concluded that the medieval catapult plans and drawings, which depicted the arm of the catapult in a perpendicular position, as in A , figure , were incorrect. My surmise was that a catapult design with a perpendicular arm would merely bowl its stone along the ground, on the principle that the stone was retained in the cup of the catapult arm till the latter was checked by the cross-bar.
Carrying out this idea, I placed the winches of the first catapult I made in front of the uprights and not behind them as in the weapon here described. By this catapult design the arm when released had of course an upward inclination when checked by its cross-bar.
Such a position for example as half-way between C and A , figure The result of this intended improvement on the ancient catapult design was: With a Sloped Arm 1. The cross-bar which checked the arm of the catapult was soon knocked loose through being struck in an upward direction.
The range of the projectile was unsatisfactory through the catapult arm being wound down only a short distance from its state of rest. The projectile - as in the case of a perpendicular arm - left its cup a considerable time before the catapult arm encountered the cross-bar. The cross-bar was struck a level blow, or one that was taken by the three supports which lean against its center and ends. The range of the projectile was much increased owing to the additional distance the catapult arm was wound down, and which caused the skein of cord to be far more tightly twisted than it was when the arm rested against the cross-bar in a sloping position before it was pulled back.
The projectile left the cup of the catapult arm as shown at C , figure , and as it did with a sloped arm. Detailed Catapult Plans Design Figure 95 shows the large front cross-piece IV , figure , between the sides of the catapult, as well as the three supports that hold the uprights and the cross-bar from movement when the latter is violently struck by the released arm.
Click Here to See a Catapult Animation. Figure shows the catapult arm, the rope which pulls down the arm, the slip hook for releasing the arm when it is wound down, the winding roller, the upper edge of the skein of cord, the winches, and the other parts of the catapult previously described.
We also see in figure the padded cushion against which the catapult arm strikes with terrific force when its upper end is checked by the cross-bar. The cushion is of the same depth as the cross bar. It is 16 in. It is made of soft hide, doubled and packed with horsehair, and should be nailed to the catapult cross-bar. Without this protection the catapult arm and cross bar would soon be shattered.
The catapult arm of ash, straight grained and without a knot or shake is 7 ft. It tapers from a width of 8 in. The tendency of the arm of a catapult is always to draw out of the skein of cord, in which its butt end is placed.
This is the result of the strain applied to the arm when it is being wound down by the roller. To prevent this slipping of the arm its butt end should be slightly increased in bulk, as shown in figure The cup or circular hollow at the end of the catapult arm - in which the stone is laid is 5 in.
The arm should be tightly bound at short intervals with lashings of quarter inch cord, figure Sometimes an arm will endure the great strain applied to it from the first and show no sign of fracture, though it may bend not a little when, it is wound down to its full extent. It is, however, probable that the first arm or two tried in the catapult will give way, especially if too much initial pressure is put upon them.
The arm should be tested by degrees and only pulled down its full distance after several trials at shorter ones. The ancients had the same difficulty in obtaining arms for their large catapults that I have experienced with smaller ones.
For this reason their engineers constructed the arm of a catapult of three longitudinal pieces. They first fastened three smooth and closely fitting planks together with glue and with small rivets; then they shaped the planks, thus held together, into an arm of correct size and outline.
The catapult arm, except its enlarged head end, was next wrapped tightly round its entire length with several layers, one above the other, of strong linen soaked in glue, the linen being cut in strips about 3 in.
Finally strong cord, also soaked in glue, was closely lashed over the linen from the butt end of the catapult arm to the cup for the stone. The arm was made on the same principle as a carriage spring, or a longbow of several pieces, and was infinitely stronger and more elastic than one formed of solid wood.
The Catapult Winches. Catapult - Catapult Winches. I - Surface view of one of the catapult winches and its plate. II - Side view of a winch as fitted in the catapult, with one end of the skein in position over the cross-bar of the large wheel of the winch. III - Side view of the large wheel of the winch. IV - Winch cross-bar. V - Perspective view of the large wheel and pinion wheel of the winch.
These are the most important parts of the catapult, and generate its projectile force. However carefully a catapult may be built, its effectiveness chiefly depends upon the two winches that twist the skein of cord in which its arm works.
The catapult plans in figure show a winch and its cross-bar in various positions. In the catapult plans I am describing, the dimensions of each winch are : Large Wheel. Its bore i. Total length of the wheel, 8 in. Length of its flange that fits through the iron plate, 3 in. Pinion Wheel. Its length, 4 in. The projecting ends of the spindles of the pinion wheels are each 2 in.
On these ends heavy spanners are fitted for twisting up the catapults's skein of cord see below. Twisting up the skein of cord by means of the winches. Winding down the catapult arm. Releasing the catapult arm when fully wound down. Catapult - Skein of Cord in Various Stages. We will now conclude that our catapult is ready for its skein of cord, its winches being in position one on each side of the framework.
In the first catapult I made I fitted a skein of thick rope for the arm to work between, but I found it was impossible to put an even strain upon the rope when twisting it up with the winches. After a series of catapult experiments with various kinds of cordage, I discovered that the finer the cord used within reason, the more elastic and compact was the skein and hence the less its liability to break. The fracture of a few strands of a large skein of fine cord is of no consequence, but the breaking of one stout rope amid a skein of a dozen lengths of such rope, means a noticeable loss of power.
The ancients were well aware of this and made the skeins of their catapults of thin cords of twisted hair. In cases of emergency, woman's hair was made into skeins for catapults and balistas, and of all material nothing was so elastic or enduring for this purpose.
When the inhabitants of Carthage commenced the heroic defense of their city B. In various modern works we read of how the noble matrons of Carthage cut off their long tresses and twisted them into ropes for catapults.
At the siege of Salona by Marcus Octavius, one of Pompey's generals, the Roman women cut off their hair that it might be made into ropes for the catapults of the besieged.
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