Suspension ideas, and some sketches

One of the sketches from school, done during free time. Much work needs to be done, but this might suffice for the 17 degree decline/incline. Might be costly.

 

In my experience, Air Bags are the easiest way to control the ride height. This is important especially since the cabin should line up perfectly with the platform every time it pulls into the station, to allow easy access to the people with wheel chairs.

As the passenger boards the cabin, the air bags should work to counter act the weight. The sensor on the cabin, paired with the reflector of some sort from the platform should work together to provide feed back achieving the perfect ride height. The airbags could also double as dampers for the vibration generated from the tracks and the wheels.

The 2 magnetically controlled coil overs work to keep the cabin level at all times. This design as of right now rely on the gravity to do its job, but the magnetically controlled dampers would allow fast initial movement followed by stiffening to decrease/cancel the swinging of the cabin, holding it in its place. In addition, these could also keep the cabin from swinging, during acceleration and deceleration. ( At this point the maximum speed of the car is approximated at 50 mph, and the decline/incline of the tracks are understood to not exceed 17 degree angle)

 

Active Suspension Group

The suspension for our project is going to be one of its kind. There aren't anything that can be directly pulled out and implemented in our project. Even though there are many suspended vehicle designs such as gondolas at ski resorts, or even roller coasters at theme parks, they cannot be implemented in our design, something has to be innovated. Gondolas for example sway with the wind, stays upright with elevation, but still swings back and forth due to acceleration, and the roller coasters are attached with minimal to no vibration dampening systems. Our design needs to satisfy the following issues: cannot allow side swaying in the wind, no jerking back and forth due to acceleration and deceleration, and being able to keep the bogie parallel to the ground while the track elevation changes. So this basically takes out the use of mechanical suspension designs. What's left is: electronically controlled designs. The bogie's position has to be continuously monitored, as well as it "sag" due to weight of the passengers, as the bogie needs to align itself perfectly with the station platform to allow easy access to the disabled passengers with wheelchairs. Most of the luxury cars nowadays are equipped with Active Suspension systems that utilize air compressors or magnetic fluids, to ensure comfort to its passengers. This is where our work gets extremely difficult. But our best bet so far is to utilize the electronically controlled magnetic suspension system. See Figure 1 below, to see how to interior works on the dampers, utilizing the magnetic current to manipulate the fluid flow, stiffening and softening the suspension travel.

 

http://www.cvel.clemson.edu/auto/AuE835_Projects_2011/Shinde_project.html
Figure 1: Cross section of the Magnetic Suspension Damper

This alone couldn't solve our problem, there needs to be many simulations and calculations to complete, in order to get the mechanical design of the whole system, and many electrical sensors, and actuators must be used. For example, there could be a small sensor on the side of the bogie, which senses the position of the bogie relative to the station, and it compensates for the weight, and electronically elevates/compensates for the weight. So the bogie would still ride comfortably, while arriving at the station, perfectly aligned to the platform, See Figure 2 below for the illustration.

Meeting, September 2nd, 2015

Meeting of our class was held at the Spartan Superway Project's warehouse located at 128 St. John street, downtown San Jose. The meeting began with introduction of the mentors, then transitioned to the introduction of the new members (students) of the team. The students' introduction consisted of their findings from the previous students' reports, what stood out to them, what has been done, what sparked their interests, and what they hope to bring the project. During the presentations, the announcement for the upcoming event has been made for September 19th, where we will be presenting our model. However due to work, I will not be attending the event, but will be helping out in advance, with the prep work.

After the presentations,  we have taken a brief tour around the workshop, and familiarized ourselves with the projects from the previous years. Upon the completion of the tour, the students broke into smaller groups to work on what they sought fit. I have gone to the Full Scale group, which concentrates on designing the full scale lane switching mechanisms, suspension, and how the actual tracks could look like. The subgroup of Active Suspension Group has sparked my interest the most, so I have joined Matt, Dale, and Scott, to take on the project. Another subgroup that I would be interested is designing the interior of the bogie, specifically how it could be easily accessed by the disabled people and their wheelchairs.

The previous year's suspension design and the concept had a critical flaw, as well as deemed not sophisticated enough to be implemented in our project, so we realized we needed to come up with a completely new design, this year. The full scale model's suspension was a direct connection, just to show the perspective of how to bogie could look like, suspended from the track system. Unlike most of the other groups, we do not have any previous ideas and designs to work off of, which makes our part, way more exciting. During our 4 man sub group, there weren't much brainstorming ideas, however, it was a critical bonding moment, in which we all introduced ourselves, and shared our interests and hobbies, which lead us to this point. Our next class would be surely more productive. I am so excited to take on this journey!

Introduction

I am a Senior Mechanical Engineering student at San Jose State University. I have recently had the privilege of joining the  Active Suspension Team, for the Spartan Superway Project. I have always been enthusiastic about off road vehicles, specifically lifting and increasing the suspension travel, while keeping the vehicle balanced. When the opportunity arose to be involved in the active suspension design and fabricating, I have jumped on board right away! This project has presented a big opportunity to improve and challenge my skills in CAD, and ANSYS software programs, as well as making new friends, and developing stronger communication skills. Based on the experience I acquire through working on this project, I hope to further my knowledge and gain essential skills to get into the automotive industry. Overall, i am very excited to be on this team, and working with everyone involved in it.