1. Engineering Challenge 20041. Engineering Challenge 2004Constructing and Testing

Mechanically Powered Launcher (MPL)By EIR Harry Baker February - March 2004

Sponsored by:

Constructing and Testing

Mechanically Powered Launcher (MPL)By EIR Harry Baker February - March 2004

Sponsored by:

The Challenge• History

– In 2004, the rovers Spirit (NASA) and Beagle 2 (ESA) reported important mineral finds on the surface rocks of Mars

– Today (2015), the first colony on Mars has just been established

• The scientists of the colony have discovered new minerals and need to urgently send them back to earth.

• The colony has very few building materials to spare but decided to devise a launcher to send a capsule in orbit for an Orbiter to bring back to Earth

• The capsule has to be launched at the precise angle to be able to escape Mars gravity and reach the proper altitude where the Orbiter is.

The Challenge • Design Standards

– The “capsule” (table-tennis or ping-pong ball - provided) will be placed on the launcher at the time of testing. An adequate opening and holding mechanism should therefore be in place.

– Only the materials listed are allowed. Decorations are allowed as long as they do not add structural or mechanical capacity to MPL.

– The MPL should fit completely assembled into a standard photocopy paper (8 ½ x 11 sheets) box. (29 cm wide x 44 cm long x 23 cm high)

An oversize MPL will be disqualified.

– All types of launchers are allowed (catapult, trebuchet, cross-bow, etc.) as long as they are built with the materials listed

The Challenge (continued)

• Construction Tips:– Accuracy and repeatability will be key to the success of the mission.

Make sure the launch mechanism is properly calibrated to that you obtain the same results test launch after launch.

– Ensure the MPL is sturdy to survive the school challenge, the trip, and the final testing

– If there are delicate parts in your MPL, make sure you make some “spares” that can be easily fitted in case of damage during the competition.

The Challenge (continued)• Main Elements

– Testing: • the MPL will be placed on its pad and aimed at the target (hoop). The MPL

Team representative will be responsible for placing and operating the MPL.

– School competition measurements:– Pass through the hoop (hoop size may be decreased to arrive to winning

teams – see set-up later)• The overall school winner + the top 2 teams from each CLASS participating

will go to the finals at the museum on March 1.

– Museum finals:• Same testing as for school competition (see set-up)• Measurements: weight • Creativity in design and construction and oral presentation (posters of the MPL

are encouraged)

The Challenge (continued)• Testing set up

Start diameter: 1m

Reduce to .75, .5, .3, .2 m if necessary

2 m from base of MPL to centre of hoop

6m from edge of launch pad to vertical line of hoop

Key Role: Encourage group problem-solving rather than providing correct answers

Role of Teacher– Integrate activity into curriculum

– Organize class into teams– Guide engineer in student interactions– Classroom management & discipline– Carry on activity in absence of engineer

Role of Engineer– Introduce design challenge to students– Relevant pre-design activities for students – Acts as a guide / facilitator– Organizes school based competition with teacher

Canada Science & Technology Museum Morning OR Afternoon Student Admission fees – none (only for teams participating in the finals) Teachers to arrange buses Overall school winner + two Teams per class Competition in Round - robin format to determine finalists

Other students in the class may visit Museum – at own cost– Participate in Museum demonstrations, treasure hunts, etc.

NEW Challenge 2004 Final Event: Monday, March 1

Part 1 - End

Questions ?

Part 2 – Teachers

• Curriculum Links

• Forces

Overall expectations / Basic concepts : Demonstrate an understanding of the effect of forces acting on different

structures and mechanisms

Design and make load bearing structures and different mechanisms, and investigate the forces acting on them

Evaluate the design of systems that include structures and mechanisms, and identify modifications to improve their effectiveness.

Develop skills of design, inquiry and communication: - Make a mechanical system that performs a function- Cut, join and rearrange pliable and rigid materials

Curriculum Links: Grade 5Forces Acting on Structures and Mechanisms

Curriculum Links: Grade 6 - Motion Basic Concepts: - demonstrate awareness that a moving mass has kinetic energy that can be

transferred to a stationary object;

- investigate ways of reducing friction so that an object can be moved easily.

Developing skills in inquiry, design, and communication - design and make mechanical devices that change the direction and speed of an

input to produce a desired output and that perform a useful function;

- formulate questions about and identify needs and problems related to structures;

- communicate the procedures and results of investigations for specific purposes and to specific audiences, including oral presentations  

Part 2 – Engineers

Principles:

• Forces

• Structures

• Motion

Forces• Main types of forces

– Tension (pull): example, cables• holding a chandelier• towing a car• suspension bridge

– Compression (push), example, steel tubes• legs of the chair or table• electric tower• columns in a building

– Friction

• Effects of gravity

Structural Elements

• Bending and breaking– Structures can be made of flexible (bend easily) components

or rigid (do not bend under force but break) components.• A diving board is flexible• The roof a house is rigid

– When the forces acting on a structure are stronger than the strength of one of its components …. the structure begins to fail (break) and may collapse.

Structural Elements (continued)

• Joints– Joints (connections) are used to connect members together to:

• make longer members with short ones• make different shapes (geometry)• make members move relative to one another

– If not properly designed and built, joints can become the weakest part of the structure

• Reinforcement– Reinforcing is the act of strengthening the original material to

make it withstand stronger forces

Effects of Shapes

• Geometric shapes have particular stability properties

Motion

Newton’s Cannon

• Explore:– What would happen if the cannon was fired on the Moon?

On Pluto?

No gravity With Earth’s gravity

Newton’s motion Laws applied to MPL(1)

• Observe the movement of the ball

• Comments?

Click on the image to start animation

Animation courtesy of Gabrielle Félio, Grade 6

Newton’s motion Laws applied to MPL(2)

• Observe the movement of the ball

• Comments?

Click on the image to start animation

Animation courtesy of Gabrielle Félio, Grade 6

Some resources on the internet

http://www.trebuchet.com/plans.html

good links to various sites where to find catapult type plans

http://www.fryerskits.demon.co.uk/treb/

detailed templates for building an paper trebuchet. Some good ideas for the MPL

http://www.glenbrook.k12.il.us/gbssci/phys/Class/BBoard.html

the Physics Classroom – all about energy, etc..

The End

Have fun !