Current Progression

We have recently learned how to add percent completion to the project libre project. Here is the current picture of the timeline in gantt chart.

Due to some setback, from the gathering of materials to getting space at the woodshop, we are set back a week.
So far, we are 25% done the physical model, and plan to do the visual analysis this week.

Completed 3D Model

For this week's assignment we needed to complete the 3d model of the CN Tower and research on the foundation of the CN Tower.

Creo Parametric Models :

 This is how the CN Tower mainly looks like with an antenna, 360 revolving restaurant, glass elevator, three wings, and the foundation of caissons.

Dimensions of the Antenna, top part of the CN Tower. The base of the sketching is the radius of the antenna. This part of the CN Tower was configured by adding extrusion and protrusion.

 The research for the foundation of the CN Tower was difficult but a primary source such as Engineering-News Record provided sufficient information. "The tower is anchored by four 30-in dia caissons drilled through 30 ft of earth overburden and as much as 90 ft into shale and one caisson drilled to 350 ft.

 
 
The base, wings, and 360 revolving part of the CN Tower was all made with protrusions and extrusions just like the antenna. The assembly of the model looked like this :

The dimensions are based on a Sketch Up drawing which served as our primary source to make the 3D model.

The main challenges in making the 3D model was not having the right dimensions before making this model. The previous model was completely based on researched dimensions off the web. However, the Sketch Up image gave the right dimensions. While assembling the parts in Creo Parametric, some of them did not constraint together correctly. We went through basic trial and error to solve the problem. When creating the wings of the tower to be constraint to the tower, one of them were not inverted correctly when modifying the radius to curve the wing. The solution to this problem was to create the same part with the same dimensions but this time, it was flipped from the vertical axis. 

For this week's assignment, it was important to learn the main foundation of the CN Tower which is essential to our physical model of the tower. It was hard to understand the Creo Parametric tools to create the bulge of the wings. With some basic research and tutorials, everything started to come together. It was fun making parts of the bridge and being able to put it together as everyone put in team effort. 

We have finally gathered all the materials for the CN Tower. We will be working on the physical model this week at the wood shop. 

Gathered Materials

At this point we have gathered some materials to make the physical model which is the motor with wires that could represent the 360 restaurant of the tower, LED lights that could surround the motor, and the syringe to represent the antenna of the tower. For the rest of the model, we will be using wood which will later be obtained from a hardware shop around Drexel University.

Use of Visual Analysis

To model the Canadian National Tower, the use of Visual Analysis is required to define the foundations of the tower such as the weight loads, visual images of how the tower is affected from weight loads, and modifying certain members. For this week, a visual analysis problem was given to us to gain a better understanding of how to use Visual Analysis. The following picture is what we had to analyze :

After putting this Visual Analysis file into the program, a result/report view reported the problem was that "A negative stiffness diagonal  has been found at node: 022 Z-Translation Check your model for stability problems near this location." The solution to this problem was to adjust the nodes, add a few members, and make some points fixed and free.

The first revision was done by implementing a type of Pratt Truss because during the Bridge Design in Engineering Design Laboratory, it was found to be the strongest truss out of the main three of Howe, Pratt, and Warren. After making these modifications, the same problem was still occurring with negative stiffness diagonals. Some adjustments were applied to the vertical part of the bridge to eliminate these problems.

The result/report view was displayed correctly without any further problems. The left picture is the newly modified version and the right picture is the correctly displayed result view. 

Visual Analysis techniques were learned thanks to watching some tutorials and making several modifications to the assignment. It was difficult modifying some of the nodes and members because of the snap modes. It was fun messing around with the members to test how the bridge would bend and pushed to the ground. It was annoying constantly dealing with the problem of negative stiffness. 

The main challenge right now is finding the right 3D rendering program to make a 3D model of the CN Tower that would work along side with Visual Analysis. Right now we are still using Creo Parametric for the model.

Week 2 3-D Model Progress

This is our 3-D of the CN Tower so far. The base of the tower looks wider than normal. The challenge while making the 3D model was the diameters of the tower were being estimated. The dimensions of the tower could not be found. The model will be updated alongside with the visual analysis model.

All the parts were made from extruded protrusion and revolved protrusion in Creo Parametric.

The design for the 360 restaurant came from this image:

The Antenna design came from this image:

Both images came from : http://en.wikipedia.org/wiki/CN_Tower

Gathered Information

General Information about the Canadian National Tower

The CN Tower started its construction in February 6, 1973.

It was opened to the public on June 26, 1976.

It costed $63 million to build the CN Tower.

The tower stands at 553.33 meters (World's tallest tower from 1976-2010)

The world's highest wine cellar at 351 meters above ground.

Holds over 500 events every year and has 2 million annual international visitors.

LED system to signify the date (ie. red for world AIDS day).

The foundation is 6.71 meters deep with over 7000 cubic meters of concrete and 500 tons of steel.
The antenna was in 44 parts, before assembled.

Updated Timeline

Using ProjectLibre to make a timeline. Subject to change.

Proposed Idea for ENGR 103 - The CN Tower

Engineering Design Laboratory III

Faculty Member : Emin Aktan

Teaching Fellow : Ben Cohen

Title : Dissecting Constructed Systems

Theme : Infrastructure

Topic : The structure that we will be working on is the CN Tower.

Some Description : 

This Canadian National Tower is located in Toronto, Ontario, Canada. 

The height from the bottom to the top of the antenna spire is 553.33 meters.
Serve as center of communication in Toronto.

Expected Timeline of Project