Hyperloop - my capsule improvement suggestions to Elon Musk's design
In August 2013 Elon Musk announced a proposed 5th mode of transport -- the Hyperloop. He published the design open-source to the internet and requested critical feedback.
While I can't fault the science and physics I did have a few issues with the design and ergonomics.
1. According to most of the published renders the pod/capsule and tube did not feature any windows. I think people would want to see out, to see the sky, the sun, the rain -- they don't want to be confined to a windowless space not much bigger than a coffin. Therefore I propose airline style windows to the pod and tube.
2. The size of the pod -- Elon proposed 2 different sizes. One that was 4m in diamater (large enough to transport a car) - and one that was very small, only 1.3m (4 feet) in diamater. This is the one that appeared in most renders and was budgeted at $6bn. This smaller design featured 2 abreast seating with no aisle. I think this is too big a compromise on size. I therefore propose a single, circular design, 2m in diamater that would feature 2 abreast seating but with an aisle in the middle. Elon stated the ride would be very smooth -- therefore there is no need for passengers to remain strapped in. These are just a few of the key advantages I see in this design:
Freedom (to travelling companions, visit children, the elderly), buy drinks. People won't want to remain confined to a seat for 30minutes+
Familiarity -- it will feel like a learjet or train. 1.3m is too claustrophobic.
-- Access to a toilet. Many people could go 30minutes without needing the loo -- but, if you tell them they can't go for 30 minutes people might feel different! Passsengers might feel unwell or sick, and you don't want accidents in a narrow, confined 4 foot diamater tube. If the route was expanded, or if there was a breakdown then the journey might take hours.
-- The slightly larger design also allows the seats to be less reclined allowing for an estimated 50% increase in seats per pod length. I also suggest that the pods could be daisy-chained together like train carriages allowing for a multi-fold increase in passenger numbers. This would help to achieve the $20 trip that Elon proposed even if costs increased.
3. A circular pod in a circular tube. The design Elon proposed appeared to feature an almost square vehicle inside a circular tube. I don't think this design is the most efficient -- especially when the vehicle needs to go round corners. A circular pod allows the pod to bank up the side of the tube just like a person in a waterslide.
I produced this cross-section in Google Sketchup to show how I think a 2m diamater capsule would look.