Bridges Project #3 Introduction to Manufacturing

Objectives After completing this activity, students will be able to: to: State and describe how technology satisfied our needs and wants throughout the ages State and describe different types of materials and why or why not they were used on/in buildings and bridges State and describe different structural shapes State and describe the different types of bridges. State and describe the different types of stresses that affect a bridge. Explain where your project’s problem areas are or will be State the processes involved in creating a Bridge. Create a Bridge that is capable of spanning an 8-foot distance while supporting my R/C vehicle being driven across it and back by you.

Content We have all driven over or walked over a bridge at some point in our lives. Some are mainly for driving across while other are only for walking. Bridges are pretty fascinating structures. There are many different types of bridges but the suspension bridge is the one I want to focus on the most for this project. Your suspension bridge is going to span an 8-foot distance, and must do so with no support from the floor or the ceiling. It must support my R/C vehicle, without you holding the bridge, all the way across it and back again..

Stresses Compression Stress is the stress caused by an object being pushed from two opposing sides. In the case of your newspaper chairs it is the force caused when you sit on the seat and legs are being pushed down to the floor. Tension Stress is the stress caused by an object being pulled apart. On your chairs the tension will be present on the seat, arms, and back of the chair.

Stresses Torsion Stress is the stress caused by an object being twisted. If the legs on the chair are not structured and supported correctly your chair could twist and won’t work. Also if the legs are not constructed properly they could also twist. Shear Stress is the stress caused by an object being torn or separated from itself. On your chairs the shear stress will be present if you don’t pack the legs correctly.

Stresses You already learned about the stresses from the Newspaper Chair project. Those same stresses will affect your bridge all over, maybe not when it is just set up but when the truck drives over it you will see it really start to move. It is all in the design and attention to the stresses.

Materials NO MAGAZINES OR FLYERS Newspaper Masking Tape, any size I will provide 2 rolls per group, if you need more rolls you are responsible for bringing them in.

Challenge Each group of 2 students will design, sketch, and construct a Newspaper Chair in the Construction Lab. The Sketches are random ideas of your thoughts but there should be a minimum of 4. From those 4 sketches select 1, draw it in detail using a ruler and straight lines (no freehand drawing). Be sure to include dimensions on your Initial Drawings. When the project is complete you will be required to complete the evaluation form and do a Final Drawing. The Final Drawing compares what your Energy Launcher ended up looking like (again, no freehand drawing, use rulers) to what you drew for your Initial Drawing. Your grade is broken down into 3 parts be sure to see the Evaluation part for further explanation. Each group of 2 students will design, sketch, and construct a Newspaper Chair in the Construction Lab. The Sketches are random ideas of your thoughts but there should be a minimum of 4. From those 4 sketches select 1, draw it in detail using a ruler and straight lines (no freehand drawing). Be sure to include dimensions on your Initial Drawings. When the project is complete you will be required to complete the evaluation form and do a Final Drawing. The Final Drawing compares what your Energy Launcher ended up looking like (again, no freehand drawing, use rulers) to what you drew for your Initial Drawing. Your grade is broken down into 3 parts be sure to see the Evaluation part for further explanation.

Challenge Your grade for part 1 depends on how close to your Initial Drawing you constructed your Newspaper Chair. The closer it resembles your Initial Drawing, the better your grade will be. The more changes you make or extra pieces you add the lower your grade will be. There are many ways to accomplish this task and you will have to keep a steady working pace to ensure that the chairs are done on time. Part 2 is that the Newspaper chair must hold the weight of each member of the group and Mr. Bogen. The chair must have 4 legs, a back to it, and arm rests. The legs must be the height of the newspapers when they are open in reading position (about 2 to 2.5 feet long). The back can be designed to your liking but must be a minimum of 18” high with arm rests that are a minimum of 8” high. The armrests don’t have to be tied into the back but it is a good idea to rely on the armrests to hold that back up. Your grade for part 1 depends on how close to your Initial Drawing you constructed your Newspaper Chair. The closer it resembles your Initial Drawing, the better your grade will be. The more changes you make or extra pieces you add the lower your grade will be. There are many ways to accomplish this task and you will have to keep a steady working pace to ensure that the chairs are done on time. Part 2 is that the Newspaper chair must hold the weight of each member of the group and Mr. Bogen. The chair must have 4 legs, a back to it, and arm rests. The legs must be the height of the newspapers when they are open in reading position (about 2 to 2.5 feet long). The back can be designed to your liking but must be a minimum of 18” high with arm rests that are a minimum of 8” high. The armrests don’t have to be tied into the back but it is a good idea to rely on the armrests to hold that back up.

Challenge Your seat are can look like anything you wish but must be a covered area, no open style seats where people can fall through. The seats must be ON TOP of the legs so you rely on the strength of the legs to carry the weight of you. The chair must be solid which means that you cannot rely on leaning or balancing your chair to get it to work. The chair must be made using only newspaper and masking tape, no exceptions. You don’t need a lot of tape to do this project, so I am giving you 2 rolls of masking tape per group. If you need more tape you must bring it in from home and can bring in as many rolls as possible. We will be weighing these projects and part 3 of your grade depends on how light you can make the chairs. The idea is to make the strongest and lightest newspaper chair. The lighter the chair the better the grade IF IT HOLDS. It should be less than 45 lbs when done.

Challenge A hint is to make your chair work first, and then start to slowly remove layers of paper until you feel you can’t without it breaking down. All work to this project must be done in class. You cannot bring this project home to work on it unless I give you permission. I do retain the right to change any aspect of this project at any time if I find that the effort going into the project is less than adequate. I expect more than the minimum on this project. Before construction can be done on this project you must first sketch the chair complete with arms and a back. Good luck.

Procedures Brainstorm ideas and sketch 4 of them onto 2 pieces of paper Choose a design that you like the best, draw an initial drawing of it with dimensions Use the supplied materials to create the Newspaper Chair Finish the Newspaper Chair using a filler and any color paint you choose or vinyl

Evaluation Sketches and Initial Drawings are a separate grade worth 100 points There is a final drawing and an reflective worksheet that counts as a separate grade of 100 points See Attached Rubric Remember that there is no fooling around in the lab Always wear your safety glasses or you will be removed from class

Evaluation Project works repeatedly and is sturdy Project is lighter than 45 lbs Project held both group members and Mr. Bogen successfully with no balancing Project resembled the Initial Drawing Student shows above average effort Student shows above average safety skills 100 Points

Evaluation Project works sometimes and is somewhat sturdy Project is lighter than 60 lbs. Project held both group members and Mr. Bogen successfully with no balancing Project somewhat resembled the Initial Drawing with minimal changes Student shows average effort Student shows average safety skills 75 points

Evaluation Project works sometimes Project has a latching mechanism that works sometimes Project launches a baseball forwards less than 30 feet and not into the box Project looks like Initial Drawing with exceptional to moderate changes Student shows moderate effort Student not allowed in class if not demonstrating proper safety skills 50 points

Evaluation Project does not work Project does not have latching mechanism Project doesn’t launch baseball Project does not look like drawing at all Student shows no effort Student not allowed in class if not demonstrating proper safety skills 0 points