Overview of the Roller Coaster

• Ride Time: 1.5 minutes

• Ride Length: 1516.3 meters

• Supports every 20 meters

• Propulsion Method: Linear Induction Motors (LIM)

• Three different locations for LIMs where the acceleration/deceleration needed was 0.5 G, 0.25 G, and -0.4 G respectively between the three locations

• Ride Cart: 1 cart fits 6 people and there will be 5 carts connected

The first step was to create a NoLimits model to calculate the dynamics. These calculations were used to determine the accelerations and assess whether a person could withstand them. Initially, I collaborated with the team to develop an Excel document that calculated acceleration from the NoLimits export data based on the position throughout the track. To ensure the accuracy of these calculations, I created a SolidWorks model with assigned materials and weights for the vehicle cart. I also added a model of a seat and person to find the center of gravity.

The weights of the people in the seats needed to be adjusted to account for three different scenarios: 300 lb people filling all the seats, 300 lb people filling half the seats, and 150 lb people filling all the seats. With these adjustments, the dynamics calculations became accurate. The accelerations were then compared to ASTM F2291 standards, and after a few iterations, they were found to be within the maximum allowable limits.

Design and Analysis of the Track

The design and analysis of the track began with identifying critical points with the highest accelerations and forces, particularly focusing on the vertical loop in the track. For the stress analysis, I was responsible for calculating the yield and deflection using hand calculations. I analyzed three critical points: the beginning of the vertical loop, the end of the vertical loop, and a 40-degree turn.

In addition to performing hand calculations for yield and deflection, I created track sections for these critical points in SolidWorks and conducted Finite Element Analysis (FEA) on the track sections in ANSYS. After several iterations, the optimal cross-section of the track was determined, and AISI 1018 steel was chosen as the material. The FEA and stress analysis process, as well as the results, are presented in the pictures below. The project required a minimum Factor of Safety (FOS) of 8.

Roller coaster Emergency Brake and Failure Mode and Effects Analysis (FMEA)

I was responsible for selecting and implementing a fail-safe emergency brake system and ultimately chose the Cincinnati Full Brake, a pneumatic brake with a standard solid brass lining for steel brake fins. This design ensures that if power is cut off, the pneumatic system will close the emergency brake, stopping the rollercoaster in case of emergencies. Three emergency brake locations were chosen, corresponding to three different blocks throughout the roller coaster where carts operate in each block.

I also performed calculations to determine the necessary length of the brake track to stop the rollercoaster in an emergency at the most extreme position of the emergency brakes, which amounted to 50.4 meters.

A Failure Mode and Effects Analysis (FMEA) was conducted for the emergency brake system, where we listed the possible failure modes of all components. We then calculated the Risk Priority Number (RPN) based on three criteria: effect, occurrence, and detection. I created the criteria for rating these factors. In our team of four, I analyzed a quarter of the components in the emergency brake system, identifying 19 different failure modes for my components and calculating their RPNs. After identifying the top five RPNs, we proposed solutions to reduce these RPNs to below our cutoff value, ensuring the reliability and safety of the emergency brake system.