The first thing which comes into my mind – A must do prank ! 😛
A Pythagorean Cup OR a Greedy Cupis a form of a drinking cup which forces its user to consume less alcohol. It allows the user to fill the cup with wine, alcohol or any other liquid up to a certain level. If the user fills only up to this level, one can enjoy his drink in peace. But if adds more of it by filling it more than the certain limit , the cup spills its entire content out of the bottom (onto the lap of a greedy drinker). more “Pythagorean Cup – The clever mischievous cup !”
Engineers at JPL (Jet Propulsion Laboratory) are working on a new class of robotic probe designed to stay aloft for a long time without wings or hot-air balloons in atmospheres of giant planets.
There is no shortage of
something different, challenging & cool things
at NASA & we know that very well. One of them is this- WINDBOTS, the new class of robots.
Unlike moon & Mars which are already been explored by the robotic rovers, the giant gas planets like Jupiter & Saturn have no solid surface on which the rovers can land on. Hence there was a need to think about the probes which can stay aloft for long period of time. In 1995, NASA’s Galileo spacecraft dropped off an atmospheric probe that descended into Jupiter under a parachute. The battery-powered probe survived only about an hour due to high heat and pressure as it fell into the planet’s deep atmosphere.
INSPIRATION – Every masterpiece of Engineering is been inspired by one or the another form, directly or indirectly from Nature. Here, the team is inspired by the dandelion seed.
A dandelion seed is great at staying airborne. It rotates as it falls, creating lift, which allows it to stay afloat for long time, carried by the wind. We’ll be exploring this effect on windbot designs.
says Adrian Stoica, principal investigator for the Windbots study at JPL.
POWER SOURCE – The Windbot must be able to use the energy resources available there. Solar would not be a good option as the probe would find itself on the planet’s night period for an extended period. The team thinks it might generate power by the same way some wristwatches make, by shaking. During the study, the team suspects that to harvest energy, turbulence can be used because in a dynamic, turbulent environment there are gradients – differences in energy from high to low – that can be used.
Windbots would also prove helpful to scientists to study turbulent weather on earth like tornados & hurricanes by transmitting data all the while.
The team has recently begun studying their question, thanks to a one-year, $100,000 study, funded by NASA’s Innovative Advanced Concepts (NIAC) program.
Our daily life Internal Combustion Engines used in cars & bikes can be cooled by air & water or coolant circulating around it. But what about rocket engines ? How rocket engines cooling system work ?
The engines of rocket heat up upto 6000°C. At this temperature, the metals would become so hot that they would melt & even some of them would vaporise. Circulating water or a normal coolant around it wasn’t going to help. Finally, rocket scientists have to take the engine cooling to a whole new level.more “How rocket engines cooling system work ?”
The Geneva drive or Maltese cross is a gear mechanism that translates a continuous rotation into an intermittent rotary motion. The rotating drive wheel has a pin that reaches into a slot of the driven wheel advancing it by one step. The drive wheel also has a raised circular blocking disc that locks the driven wheel in position between steps. Because the mechanism needs to be well lubricated, it is often enclosed in an oil capsule.
Internal Geneva drive :- An internal Geneva drive is a variant on the design. The axis of the drive wheel of the internal drive can have a bearing only on one side. The switch time is greater than the time the driven wheel stands still. This is also a main difference between them.
What is Switzerland known for ? for its beautiful sceneries, yea… but also for its mechanical watches- Rolex, Omega, Rado. The name derives from the device’s earliest application in mechanical watches.
Also one of the application of Geneva drive is the movie projectors. These were used earlier as the film doesn’t run continuously, instead the film was advanced frame by frame, each frame standing still in front of the lens for a very short period of time. In modern projectors, stepper motors are used.
Other applications of this mechanism include automated sampling devices, banknote counting machines, CNC machines, turret lathes & turret drills.
The external form is the more common, as it can be built smaller and can withstand higher mechanical stresses.
Get ready, for this highly UNREALISTIC jet engine… Boeing has received a patent, US 9068562, which combines inertial confinement fusion, fission, and a turbine that generates electricity. Currently this kind of engine is completely unrealistic given our mastery of fusion.
But perhaps in future this might be an excellent idea.
Lets imagine our standard jet engine of commercial jetliners.Somewhere in the middle of the engine lies a fusion chamber.A very strong number of lasers are focused on a single point.The hohlraum or pellet, which is a mixture of deuterium & tritium(isotopes of hydrogen) is kept at this point.When all the lasers are turned on at the same time, it creates massive pressure.This causes the hydrogen isotopes to fuse.Now according to the patent, the hot gases produced by the fusion are pushed out of the nozzle creating very high thrust.
Also, one of the by-products of the fusion reaction is lots of fast neutrons.The patent explains that there is a shield around the fusion chamber.The shield is made of fissionable material(for eg:-Uranium-235).The neutrons moving at high speed collide with this material resulting in production of high amount of heat.This heat is then transferred to drive the turbine which generates electricity.
Finally we are done with this fusion-fission jet engine thing.
”Suidobashi, you have a giant robot, we have a giant robot. You know what needs to happen”
says MegaBots – U.S.-based robotics company! MegaBots issued the challenge last month after giving a final touch to its Mark 2- America’s first fully-functional, giant piloted robot. Mark 2 weighs 6 tons & can be controlled by 2 pilots, shoots 1.5 kilo paint cannonballs at the speed of over 160 km/hr.
The co-founders Matt Oehrlein and Gui Cavalcanti, challenges the only other company in the world Suidobashi Heavy Industry. Suidobashi have created the giant – Kuratas, a single pilot robot which is already available commercially.
Challenge Accepted… :-
Suidobashi CEO Kogoro Kurata, responded after a week saying,
“I’ll fight. Absolutely.”
The Kuratas – named after its designer, was launched in 2012. It weighs 4.5 tons, 25% less than the Mark 2, featuring Gatling guns controlled with an advanced targeting system & heads up display(HUD).
Both the companies have one year to do the necessary preparations & modifications to win this epic robowar while no venue or date for this has been fixed.
All the sci-fi fans are eagerly waiting for this to happen; especially me 😉
In my previous article we saw about how trains turn on curved tracks. Well in automobiles, we can’t use the same principle for turning around a corner as our cars don’t run on tracks. So we cannot design our tires as the train wheels. At the beginning of auto industry, only one rear wheel was driven by the engine. But if only one wheel was driven by the engine, it had to all the work & also it couldn’t maintain a good grip on the road.
So if we drive or supply power to both the wheels, the outer wheel had to cover more distance than the inner one while taking a turn. This is why we need differential – to drive both the wheels at different speeds!
Construction of differential :-
The standard differential mainly consists of 3 parts – 1. The pinion gear 2. The ring gear & 3. The spider gear
The pinion gear transfers the power from engine to the ring gear.The spider gear lies at the inner edge of the ring gear.The spider gear is free to rotate on 2 axes-
1. along with the rotation of ring gear &
2. on its own axis(spin) Also the spider gear is connected to two more side gears.
Working of Differential :-
So, first the power is transferred from engine’s drive shaft to pinion gear, since the pinion gear & ring gear are meshed, power flows to ring gear.As the spider gear is connected with the ring gear, power flows to it. Finally from the spider gear, power gets transferred to both the side gears.
–When the vehicle moves straight, the spider gear doesn’t spin & will make BOTH the side gears rotate at same speed.
–When the vehicle moves on a curve road, the spider gear itself spins & either of the side gears move slower or faster than other one.Which will be faster & which will be slower is decided by the turn.
Make sure you watch the video. I assure you a 100% guarantee of understanding the whole thing. Here is a demonstration in the most simplest way ever possible…! you can jump to 1:56 if you want to skip the boring part.
Limited Slip Differentials or LSDs are the most modern and complicated type differentials used today in automobiles.
The biggest disadvantage of ordinary differential is when a slip condition occurs only on one wheel. The differential transmits all the power to the one which has the least resistance. This wastes too much power. Along with that, it doesn’t help the car get out of the slip condition. This is where LSDs come into action.
Limited slip differential limits the amount of torque or power transmission on one wheel and transmits it to the other wheel. This is done via adding a pre-loaded spring or clutch packs.