Trebuchet Calculator Program Source Average ratng: 9,9/10 4869 votes
- Trebuchet Calculator Program Source For Kids
Mar 31, 2007. External source of energy during the launch. The trebuchet. We will develop a computer simulation that will allow us simulate the system with different design parameters. 1All students, even those not registered in MEAM. I.3 Write a program that will allow you to change the parameters IO, mA, L1, L2. A simulator describing the physics of the trebuchet, a catapult powered by a falling counterweight. Virtual Trebuchet is a free web based trebuchet simulator. Welcome to the original version of VirtualTrebuchet! Go to VirtualTrebuchet 2.0 for the most up to date version. VirtualTrebuchet is a web based trebuchet simulator that will allow you to quickly evaluate different trebuchets.
SolidWorks was used here, although any CAD software or even a hand sketch would be ok. One advantage of 3D CAD was the ability to make an assembly and ensure a good fit for all the components, as well as smooth motion.
I've uploaded PDF's of the CAD drawings as well as a general schematic diagram for an f2k. Feel free to use them for educational or personal use. NOTE: all CAD modeling was done using student software, for educational purposes.
Using the dimensioned drawings, estimate the amount of materials needed. We spent around $300 in lumber and concrete, and several hundred dollars more on metal shafts, plates, etc. Consider cost and use whatever spare or donated materials you can find.
Try to have all the sizes of your shafts and designs for your trigger and sling release figured out at this stage, as well as how you plan to attach the shafts (welds or flanges, etc).
Consider how much weight you want to use, and size your shafts and frame accordingly. I haven't seen much information on dynamic tuning for the f2k, but we did an estimate of the static loads at the critical points and kept the stresses around 1/4 of the yield strength of the steel.
I'd also advise implementing a metal sheet on the rails, instead of bare wood. it's smoother, faster, and prevents grooves from wearing in the wood. We'd have done much better with something like this. Angle iron or steel sheet would work.
A few things to keep in mind are the optimum ratio for the arm length (2:1) , or L=3P in the schematic diagram. You want to keep the width relatively narrow, but wide enough to accommodate whatever projectiles you plan to use.
MATERIALS LIST:
-Lumber (4x4, 2x4, plywood)
-Deck Screws (lots of them)
-Carriage bolts, nuts, washers
-all thread, 1/2', 1ft sections (for sling pins)
-Harmonic Balancers ~7' dia (4X)
-Steel Shafts, various diameters
-Steel pipe, appropriate mating diameters to shafts
-Bolts for bushings
-Concrete (450+ lbs) and circular forms (OR just use gym weights)
-Steel plates
-Steel chain, 1900lb test, 3-4ft
-Door latch mechanism from a car
-Nylon rope (or other strong rope/cable)
-Nylon webbing for sling
-Axle grease
-Welding equipment
-Grinder
-Drill press
-Carpentry tools
-Paint (optional)
Trebuchet Calculator Program Source For Kids
STEM Modules and Enrichments > Trebuchet PhysicsObjective: The purpose of this unit is to learn the physics and math associated with Trebuchet Technology. In addition, students will be required to design and constructed a trebuchet to launch a clay projectile as far as possible.Students will also compete against each other in a trebuchet battle. Background: Complete the Trebuchet Vocabulary worksheet. Remember you will be tested on the definition to these terms. Review the definitions on the worksheet as a bell ringer exercise before taking the test.
Watch this short video, How to Build a Trebuchet (Mythbusters)
Launch the link to experiment with different designs for a simple virtual trebuchet ---> The success of your trebuchet will depend on the following design characteristics, choose well:
- Fulcrum location, for example the ratio between the long section (sling) and the short section (counterweight) of the throwing arm. (L2)/(L1) and ((L2 + L3)/(L1 + L4)
- The length of the sling in relationship to the length of the long section of the throwing arm. L3/L2
- The mass of the counterweight. weight of m1
- The ratio of the counterweight mass to the projectile mass. m1/m2
- The motion of the counterweight is important
- The distance the counterweight hangs from the end of the throwing arm is important. L4
- The length of the sling L3
- Overall construction quality.
- Operator skill and aim.
- ONLY adjust the Release Angle, determine the optimum angle of release.
- Refresh the screen.
- ONLY adjust the Mass of Weight, determine the optimum mass of the counterweight.
- Refresh the screen.
- ONLY adjust the Length of the Long Arm and the Length of the Short Arm. Determine the ratio for launching a projectile the furthest.
- Experiment with the settings, it's important to design and build a projectile to launch a cow as far and as accurately as possible.
- Turn on your call light and show your teacher your best launch. You must throw a cow at least 300' before beginning work on your trebuchet.
Safety (Students MUST score 100% on the following tests to work in the lab): - Launch the ABC of Hand Tool Safety 1 & ABC of Hand Tool 2 videos, complete the Hand Tool Safety Test worksheetand take the ABC of Hand Tool Safety Test
- Launch the Power and Hand Tool Safety video and complete the Portable Power Tool Safety Test worksheet and take the Power and Hand Tool Safety Test
- Launch the Drill Press Safety video and complete the Drill Press Safety Test worksheet and take the Drill Press Safety Test
- Launch the Band Saw Safety video and complete the Band Saw Safety Test worksheet and take the Band Saw Safety Test
- To prevent injury, learn the safety rules presented in the videos. Also, you will be tested on these competencies often in this class.
Click on each image below for a more detailed view Get template and 12' x 5' piece of wood
Attach template to wood as shown above | Drill five 5/32' diameter holes | Use band saw to cut throwing arm and supports |
Shape and smooth tip of throwing arm and supports using a hand file or rasp, table vise and 80 grit sandpaper
Use band saw to cut slot for counterweight Use 80 grit sand paper to remove paper template and glue from face of stock
Assemble throwing arm using 3' machine screw and three hex nuts
Attach throwing arm assembly to base of trebuchet using nails and/or wood screws (Remember to drill a countersink into the throwing arms and a pilot hole into the base) |
Hot glue trigger pin to bottom end of throwing arm | Wrap 5' string/sling around the trigger pin | Secure sling to throwing arm using duct tape |
Attach pouch to sling using sewing needle | Make a loop at the end of the sling |
Trim excess string from the end of the sling |
Use diagonal cutting pliers to cut wire to 8' |
Use pliers to bend counterweight holder to the desired shape | Nitro street racing game online.
Attach trigger to base using a small pan head screw |
Weak trebuchet because of incorrect ratio between load arm and effort arm | More effective trebuchet because of a better effort arm to load arm ratio |
Troubleshooting: Check the length of the firing pin. Check the size and shape of the poach if your projectile is launching too late or too early in the motion of the throwing arm. Calculate the ratio between the load arm and the effort arm of the throwing arm, it is crucial. Make sure your counterweight isn't hitting the throwing arms during launches. In summary, there are plenty of design issues that command your attention. The design issues cited above are just a small sampling of the problems you might encounter in troubleshooting your compound machine. Use your problem solving skills to build and operate the trebuchet with the greatest range.
According to Donald B. Siano, in his analysis of trebuchet physics (Trebuchet Mechanics, March 28, 2001), the optimal release position and design, based on his definition of 'range efficiency' is such that:
• The initial release position is such that the beam on the counterweight side makes an angle of 45° with the vertical.
• The length of the long arm of the beam (on the payload side) is 3.75 times the length of the short arm of the beam (on the counterweight side).
• The length of the sling is equal to the length of the long arm of the beam (on the payload side).
Furthermore, he recommends using a counterweight that has a mass 100 times greater than the mass of the payload. However, it is certainly possible to achieve a good design with a much lighter counterweight than this. Good Luck! Assessments: - Band Saw Test Review (100 points)
- Virtual Trebuchet Simulation (100)
- Trebuchet Vocabulary (100)
- Trebuchet Construction and Test (500)
- Trebuchet Physics Test (100)
Enrichments:- When you've finished your trebuchet project, turn on your call light and your instructor will issue you a goal post and tape measure to record the longest 'field goal' you can make with your project.
- Students who successfully construct and test the trebuchet will get a Catapult project to construct and test.
- After completing your catapult, record your accuracy and distance attempting 'field goals' using a goal post and tape measure.
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