Goliath Fall 2016
Initial Design
By: Dylan Hong (Design and Manufacturing Engineer)
Approved by Kristen Oduca (Project Manager)
Preliminary Sketch
After researching the previous semester’s Goliath design, we created our own initial design based on the size of the Samsung Galaxy S6, the 3Dot board, two motors, I2C shield, and the actual design of the 302 Goliath.
The first step of the design process is the preliminary sketch design of the Goliath. This process includes researching the 302 Goliath’s architecture, in which we found pictures and blueprints from the German Engineers w/ Goliath Demolition Vehicles 1:35 ’39 – ’45 Series shown in Figure 1 below [1].
Figure 1 – Blueprints of Goliath
With this blueprint, I was able to sketch the side panel, top panel, bottom panel, side box with wheels and tracks of the Goliath shown in Figure 2 below.
Figure 2 – Goliath Sketch
Calculations of Body Dimensions
The second step of the design process is to create a “back of the envelope” calculations regarding the body’s dimensions. Taking the dimensions of the Goliath 302, 1.5m x 0.85m x 0.56m, LxWxH, I calculated the ratio that is needed, which is 1×0.567×0.37 as shown in Figure 3 [2].
Figure 3 – Goliath Ratio
Since we decided to have the Samsung Galaxy S6 incorporated inside the body of Goliath, the basis of our dimensions were dependent on the size of the phone which is 5.65 x 2.78 x 0.27 inches [3]. For the electronic components, we initially decided on using the Tamiya Double Gearbox which has a dimensions of about 3 x 2.25 x 1.125 inches [4] and the 3DOT Board with battery is measured at approximately 2.75 x 1.5 x 0.75 inches. Also, we used the previous semester’s PCB board as an estimate of our potential PCB board, which measured at about 1.5 x 1 x 0.75 inches. All those not referenced to a link were hand measured by me. With the dimensions of the electronic components and the smartphone we determined the length of our initial design to be at 8.5 inches. This referenced length of 8.5 inches allowed us to calculate the width and height of our Goliath by using the ratio we calculated in the research blog post as shown in Figure 4.
Figure 4 – Goliath 2016 Dimensions
In comparison, our initial dimensions of 8.55 x 5.06 x 3.21 inches was very close in approximation with the ideal dimensions of 8.55 x 4.84 x 3.19 inches with a percent error of 0 x 15.7 x 0.62 %. The calculations are shown in Figure 5 below.
Figure 5 – Goliath Percent Error
The width of our initial dimensions is larger than the ideal dimensions because we needed to compensate the width of the phone including the width of the side box part, which uses up about 2 inches of the total width of the overall Goliath. A physical scaled model was created with cardboard for the purpose of mimicking the dimensions in real life as shown in Figure 6.
Figure 6 – Cardboard Goliath model