Trains are one of the least consuming means of transport, and it is mainly due to the metallic wheels and rails: there is almost no energy dissipation due to the rolling contact. Of course, not everything is so great with […]
In lay people’s minds, railway lines are composed by rails and wooden sleepers on a bed of stones. These medium-sized stones are called ballast, and it is true that they are the most common material to lay the track […]
Trains have a huge seasonal problem each autumn: leaves. Yes, leaves from the trees. And now they are testing a solution: laser beams! It sounds absurd, but it will all make sense after we get into its science.
Every autumn […]
If you have a bike, most surely you will own a helmet too. If you fall off the bike your helmet might avoid some nasty head injuries, right? That looks pretty obvious… except that it isn’t.
Lets start with a […]
Of all the seven wonders of ancient times, only the pyramids of Egypt remain on their feet. The technical means Egyptians had that many years ago for building these huge structures were extremely limited, and that is the main reason […]
Bicycles are usually regarded as the most sustainable mean of transport for urban environments. Now, when talking about sustainability, there are usually two different discussions: on the one hand, there is energy sustainability, as the fossil fuels won’t last forever […]
Is there anyone that doesn’t know the sport of curling? Just in case: curling is a winter sport played indoors where two teams take turns sliding rocks on ice, trying to place them as close as possible to the button […]
Bikes are becoming a much more interesting mean of transport in urban areas due to the local policies to minimize traffic impact on the daily city life. City councils are building bike lanes, converting streets to mixed pedestrian-bike traffic, and […]
Classic rail vehicles have rigid wheelsets: both wheels are interlocked and have the same degrees of freedom (DoF), so they share all their displacements. They also have positive conicity, this is, the wheel surface on the contact patch is conical […]
The locomotion of every moving system, alive or manufactured, is produced by the interaction between some movable components or appendages and the surrounding environment. This applies for every kind of surroundings: land, water or air. For water and air, Navier-Stokes […]