Air is the element of the AirJelly. Rather than swimming through water like the AquaJelly, it glides through the air with the aid of its central electric drive and an intelligent, adaptive mechanical system. The remote-controlled AirJelly is kept in the air by its helium-filled ballonet.
The AirJelly’s only energy source are two lithium-ion-polymer batteries, to which the central electric drive is attached. This transmits its power to a bevel gear and then to eight spur gears, which drive the eight tentacles of the jellyfish via their respective cranks. The structure of each tentacle is based on the Fin Ray Effect®. Using a peristaltic movement to drive a balloon was previously unknown in the history of aviation. The AirJelly is the first indoor flying object to use such a peristaltic propulsion system. The jellyfish glides gently through the air thanks to this new drive concept based on the reaction thrust principle.
The AirJelly steers through three-dimensional environments by shifting its weight. Its two servo motors are located at the “North pole” of the jellyfish and controlled proportionally. If the pendulum moves in one direction, the AirJelly’s centre of gravity shifts in this direction – the AirJelly is thus able to swim in any spatial direction. The propulsive force of the drive can be varied by moving the Fin Ray® tentacles more quickly or slowly.
Festo demonstrates with this exhibit that a central electric drive – combined with an intelligent mechanical system – can offer fascinating possibilities for “lighter-than-air” aviation. Festo aims to delight its customers with innovative, fascinating and intelligent solutions in both automation and didactics. It therefore offers a wide range of electric, pneumatic and hybrid drive systems, together with the respective sensors and control possibilities.
The amount of fuel your car burns is related to the power required to move it. There are several components, but, at highway speeds air resistance dominates as it goes as the cube of the velocity. Just looking at air resistance, the power required to move a car at 75 mph is about 3.4 times greater than the same car moving at 50 mph.
There are terms that cover rolling resistance (which tend to have components that depend on velocity to the first and second power), terms for running generators, cooling fans, etc (tend to have a fixed idling component and a term that goes as the square of velocity), etc...
Drive trains are engineered to have "sweet spots" - regions where mileage is highest. On most cars this falls between 40 and 60 mph (there are some cars that get much better mileage at 60 mph than 40, but almost nothing you can buy will get better mileage at 65 mph)
For most people a highway speed of no more than sixty will save a considerable amount of gas. The problem is traffic is often much faster and driving outside of average highway speed can be dangerous ... But a national speed limit of 55 or 60 mph that is enforced would probably make a big difference in fuel consumption for highway driving.
Politicians are too timid to consider measures that might work. They can't even get to the point to make citizens believe there are problems that need to be tackled. grumble - I guess I should be patriotic today and go shopping.
Revenue from the gas tax is about a fifth what we spend on the Iraq War. It is used for road and bridge construction and maintenance - something that has fallen to dangerous levels in the last decade as costs go up, but revenues are relatively flat.
There should be a recognition that fuel prices are likely to rise. Bringing on new capacity is expensive and demand is exploding. The increases have been much larger than the gas tax (which amounts to about $10 a month for the average driver) and many feel they will increase.
Perhaps a better message would be to encourage easy alternatives. The federal excise tax on gasoline is 18.4 cents a gallon - about five percent of what a driver is paying for a gallon of regular at this point. By changing driving habits it is easy to get a five percent improvement in economy. Proper inflation of tires gives most people a two to three percent improvement. Cutting back speeds and avoiding heavy pressure on the accelerator and break pedals is a big thing. Consolidating trips to cut mileage as well as make sure the engine is warm ... the list goes on. I was able to cut gas use by about twenty percent without much difficulty.
Top Gear checks out the Peel P50 - a tiny and somewhat silly car from the early 1960s that would be the worst thing imaginable for a friend and her forty inch inseam. Post WWII Europe was short on many things and there was considerable experimentation in this area, but a bike is much more practical than many of these designs and the world went in another direction.
It is reasonable to think about the right form factor for various types of transport. Somehow 3500 pounds carrying a 130 pound driver and 20 pounds of groceries seems wrong. Assuming you have safe roads, bikes and assisted bikes are going to rule on short trips in mostly good weather, but a 1000 pound vehicle could get away with a modest load of modern (lithium-ion for example) batteries and might be the basis for a neat city vehicle. Maybe even one for someone with Colleen's legs.
I've seen several references to a unit of energy called the cubic mile of oil (CMO). As you might expect it is a lot of energy. It is interesting because humanity currently consumes about that much oil a year at this point and 3 from all sources.
It has this nasty feature of making change look impossible. Individual change becomes a vanishingly small number and may even feel meaningless. My gut tells me people need to have hope and feel they are doing something positive. Better to keep energy on a human scale when talking to humans - you can get 300 to 400 miles on a gallon of Ben and Jerrys and a 1000 on peanut oil. Maybe that tells you something about the inefficiency of using a car all of the time. A TV running in the background at 300 watts represents the same amount of power as three people. If we are going to change at the grass roots, we need to understand a bit of what we are facing.
The NY Times ran a piece on Ansel Adams - be sure and check the interactive feature linked from the main article.
I was a teenager when I saw some of his prints for the first time. They taught me several things: you need to look at things carefully, even simple scenes can be fascinating, shadows and contrast are powerful and it doesn't make any sense for me to think of myself as a photographer.