Blog 2: Developing Poddy McPodface - Hyperloop prototype for SpaceX competition
What is the SpaceX competition? Why is it happening?
The SpaceX competition has provided a competitive, international arena for the design and development of Hyperloop technology. The Hyperloop concept was made entirely open source by Elon Musk in 2013 to encourage contributions from all groups with the determination to test their technical expertise. Whilst the development of prototype pods may cost tens of thousands of pounds, the track is likely to reach millions. SpaceX has affirmed their dedication to the development of Hyperloop by providing the test track, removing this major financial obstacle from many small teams.
Fig 1. Video from SpaceX competition
The competition has been run in two heats: first to refine designs, and now to manufacture functioning pods. In August, the constructed pods from 24 finalist teams will be tested on the ½ scale SpaceX test track in California. At HypED, we are currently manufacturing our own Poddy McPodface who we believe will be a strong competitor on the track.
Fig 2. Conceptual pod model
What challenges are there for Hyperloop technology?
We are at the very beginning of Hyperloop development and thus the challenges it brings are met along the design and manufacturing process. Whilst individual components of the technology can be sampled from other modes of transport (e.g. levitation from Maglev trains), many aspects of Hyperloop are novel and require in-depth engineering analysis. There are no rules of thumb to call upon. High-speed travel in confined, vacuum spaces is a unique and technically complicated problem that requires significant time and brainpower to solve.
Fig 3. CFD analysis of pod shape
Fig 4. FEA modelling of loads on bottom parts of the chassis
To tackle these challenges, several of our team members approaching the final year of studies will be dedicating Masters theses to the engineering analysis of Hyperloop. These analyses will include structural designs for both the pod and the tube, the dynamic behaviour of composite materials, levitation methods, and fire propagation in a vacuum. This list is by no means exhaustive but does provide an insight to the diversity of issues that must be overcome.
Within the University and our sponsors, we are working with research specialists in transport infrastructure, extreme environments, dynamic loading of structures and composite materials to cover the wide range of challenges faced by Hyperloop.
We have a manufacturing team with four full-time members in the workshop and an additional five working part-time. The dedication is outstanding and the hard work is paying off; Poddy McPodface is on track for completion and will be ready to ship by August 10th.
What are the other big challenges for Hyperloop to overcome?
Beyond the immediate technical challenges that must be addressed to create a working Hyperloop system, the implementation of a fully functional system presents further tests. For example, the 700mph speeds could cause serious problems should a leak develop in the tube: the intrusion of air in such a confined space could lead to shock waves, damaging both the pod and structure. Equally, a near vacuum renders air cooling virtually impossible which can be necessary for preventing damage to components. Power loss to the system requires safety systems to activate almost instantaneously to keep passengers safe. Again, the energy efficiency of the system must be optimised to keep Hyperloop feasible and environmentally friendly. Furthermore, many administrative and legislative issues are likely to arise: Right of Way, financial backing and manufacturing at such scale. We understand that these challenges require solutions, hence our team is working to find the answers alongside building Poddy McPodface.
Fig 6. Explanation of Hyperloop
The infrastructure for Hyperloop is still under discussion. The high speeds require a turning radius of over 20km to avoid undesirable G-forces; this poses challenges when navigating urban and rural landscapes, particularly in densely populated regions such as the UK. This is a key concern for the design because passengers must have a smooth journey to make the transport desirable. Ideally, the Hyperloop corridor would be perfectly straight and flat. Thus there is a large body of thought within the Hyperloop community that the corridor should be made underground to allow for non-intrusive, straight and flat tracks. We thought this was perhaps too ambitious when we started conceptualising the idea in 2016. However, a few months later Elon Musk created the Boring company with the aim to provide economical tunnel boring for subterranean infrastructure.
Fig 7. Musk's Boring Company
At HypED, we have completed economic analyses in tandem with engineering work to create a comprehensive approach to making Hyperloop a reality.
How is Poddy McPodface development progressing?
Name that dummy! Why not get involved by suggesting a name for the test dummy.....www.sciencefocus.com
Manufacturing at HypED is relentless: all critical systems and components have been ordered, with most of these already in our workshop. The spaceframe has been welded, mounts for subsystems are being prepared and the majority of dynamic components have been machined. We are now carrying out a plethora of tests to ensure all components function both individually and in conjunction with one another. Our team have tested hydraulics for the braking system, integrated the battery and control circuitry, and have successfully tested communication with the base station using control loops. Most excitingly, we are preparing the seat and harness for our first passenger - a dummy presented to us by Ruth Lee.
Fig 8. Dummy and chassis
The shell is now being made with the help of FibreGlass Works in Loanhead, where we have our students working under the supervision of experts - we believe this is a great form of sponsorship. Assembly is now underway at a subsystem scale before we move into full system assembly and testing.
What have we found most challenging?
Building a pod for the first time means that in every new step there are potential issues that may arise. We have carefully considered our system to try and foresee these problems, which has been a design challenge itself, but several unforeseen technical challenges have arisen. For example, the process of manufacturing parts with a computer numerical control (CNC) machine has proved more difficult than expected, and is by no means ‘plug & play’. The specialised parts required for Poddy McPodface were different to the standard sets of parameters used for CNC manufacturing and required abstract thinking to adapt designs.
Fig 9. Levitation ski evolution
Moreover taking our design from concept to manufacturing proved considerably more difficult than expected; our designs were often idealistic and assumed perfect availability and lead time of components. The reality of the situation meant that we had to rework the pod design to match market availability. This impacted theoretical subsystem performance which prompted further design changes: we managed to break the vicious circle of design iteration two months ago and everything is now on track for timely completion.
In regards to the competition, the biggest challenge has been the tight timeline. SpaceX announced finalist teams in April, giving 4 months for design finalisation, manufacturing, testing and packaging of Poddy McPodface to be showcased in a different continent. We are now in the manufacturing and testing stages and look forward to shipping our finished pod in under a month.
Hyperloop Blog Series
Want to find out more? The HypED team will be blogging frequently on DesignSpark over the coming months. To follow their journey, why not sign up to the DesignSpark newsletter and get updates from the team as soon as they are posted. Click here to register.
For a quick overview of the competition which was held in August watch the SpaceX video below. Stay tuned for a more in depth review from HypED.
Student team, 50 strong, propelling Hyperloop to becoming a reality. SpaceX II Competition finalists. Hyperloop One Global Competition semifinalists.
July 26, 2017 14:41