What comes to your mind when you think of April 15th?
How about a celebration of a great genius of all times Leonardo da Vinci? After all, it is his birthday.
Leonardo da Vinci stands in the category of his own. There are selected few men in history that have made such an impact on our civilization, and Leonardo rightfully takes his place among them.

Born Leonardo di ser Piero da Vinci on April 15, 1452 (old style) was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist, and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance humanist ideal. For a computer science, Leonardo da Vinci is most important as inentor of such advanced technology as flying machines, including a helicopter, the first mechanical calculator and one of the first programmable robots.
Leonardo has often been described as the archetype of the Renaissance Man, a man of “unquenchable curiosity” and “feverishly inventive imagination”. He is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived. Born out of wedlock to a notary, Piero da Vinci, and a peasant woman, Caterina, at Vinci in the region of Florence, Leonardo was educated in the studio of the renowned Florentine painter, Verrocchio. Much of his earlier working life was spent in the service of Ludovico il Moro in Milan. He later worked in Rome, Bologna and Venice, and he spent his last years in France at the home awarded him by Francis I.
Engineering and Technology Innovations
For this article let’s not review Leonardo’s fame as painter, nor journalist, but remember that he is revered for his technological ingenuity. While He made important discoveries in anatomy, civil engineering, optics, and hydrodynamics, but he did not publish his findings and they had no direct influence on later science. Leonardo da Vinci conceptualized a helicopter, a tank, concentrated solar power, a calculator, and the double hull, and he outlined a rudimentary theory of plate tectonics. Relatively few of his designs were constructed or were even feasible during his lifetime, but some of his smaller inventions, such as an automated bobbin winder and a machine for testing the tensile strength of wire, entered the world of manufacturing unheralded.
During his lifetime Leonardo was valued as an engineer. In a letter to Ludovico il Moro he claimed to be able to create all sorts of machines both for the protection of a city and for siege. When he fled to Venice in 1499 he found employment as an engineer and devised a system of moveable barricades to protect the city from attack. He also had a scheme for diverting the flow of the Arno River, a project on which Niccolò Machiavelli also worked.Leonardo’s journals include a vast number of inventions, both practical and impractical. They include musical instruments, hydraulic pumps, reversible crank mechanisms, finned mortar shells, and a steam cannon.
Flight

For much of his life, Leonardo was fascinated by the phenomenon of flight, producing many studies of the flight of birds, including his c. 1505 Codex on the Flight of Birds, as well as plans for several flying machines, including a light hang glider and a machine resembling a helicopter. The British television station Channel Four commissioned a documentary Leonardo’s Dream Machines, for broadcast in 2003. Leonardo’s machines were built and tested according to his original designs. Some of those designs proved a success, while others fared less well when practically tested.
Among Leonardo’s drawings are many that are studies of the motion of water, in particular the forms taken by fast-flowing water on striking different surfaces.
Many of these drawings depict the spiralling nature of water. The spiral form had been studied in the art of the Classical era and strict mathematical proportion had been applied to its use in art and architecture. An awareness of these rules of proportion had been revived in the early Renaissance. In Leonardo’s drawings can be seen the investigation of the spiral as it occurs in water.
Hydrodynamics
There are several elaborate drawings of water curling over an object placed at a diagonal to its course. There are several drawings of water dropping from a height and curling upwards in spiral forms. One such drawing, as well as curling waves, shows splashes and details of spray and bubbles.
Leonardo’s interest manifested itself in the drawing of streams and rivers, the action of water in eroding rocks, and the cataclysmic action of water in floods and tidal waves. The knowledge that he gained from his studies was employed in devising a range of projects, particularly in relation to the Arno River. None of the major works was brought to completion in his lifetime.
In 1502, Leonardo produced a drawing of a single span 720-foot (220 m) bridge as part of a civil engineering project for Ottoman Sultan Beyazid II of Constantinople. The bridge was intended to span an inlet at the mouth of the Bosporus known as the Golden Horn. Beyazid did not pursue the project because he believed that such a construction was impossible. Leonardo’s vision was resurrected in 2001 when a smaller bridge based on his design was constructed in Norway, and then in Turkey, when on May 17, 2006, the Turkish government decided to construct Leonardo’s bridge to span the Golden Horn.
Leonardo da Vinci today
Leonardo died on May 2, 1519, but his legacy lives on.
In the late 20th century, interest in Leonardo’s inventions escalated. There have been many projects which have sought to turn diagrams on paper into working models. One of the factors is the awareness that, although in the 15th and 16th centuries Leonardo had available a limited range of materials, modern technological advancements have made available a number of robust materials of light-weight which might turn Leonardo’s designs into reality. This is particularly the case with his designs for flying machines.
A difficulty encountered in the creation of models is that often Leonardo had not entirely thought through the mechanics of a machine before he drew it, or else he used a sort of graphic shorthand, simply not bothering to draw a gear or a lever at a point where one is essential in order to make a machine function. This lack of refinement of mechanical details can cause considerable confusion. Thus many models that are created, such as some of those on display at Clos Luce, Leonardo’s home in, do not yet work, but should work with a little mechanical tweaking.
Happy Birthday, Leonardo da Vinci!
you dont say anything about the math involved in his helecopter!!!!!!