Showing posts with label Ball Tracking. Show all posts
Showing posts with label Ball Tracking. Show all posts

Tuesday, April 16, 2013

Snickometer



Invented in the mid-1990s by English computer scientist Alan Paskett, the Snickometer is used in a slow motion display to determine whether the ball did touch the bat , even slightly to determine if it was out. Although this was used earlier in UDRS, but unlike Hawk Eye and Hot Spot currently not used in UDRS. This is also known as the Snicko.

A Snickometer works on a simple principle. Filter the ambient noise, and amplify the relevant signal. The ball hitting the bat produces a sound of a particular frequency. The stump microphone will pick up the sound of the ball hitting the bat. It first filters this sound which is of a particular frequency from all the ambient noise. This can be achieved with the help of a resonance filter. At the receiver this sound is amplified and plotted to note the variation in the sound. A sharp variation denotes the bat hitting the ball and a flat peak means the bat has hit the pad or part of the body. This plot is viewed along with the replay of the shot to synchronize the movement of the ball and the spike in plot.  So in the situation where the batsman was ruled out, a review on TV with the Snicko will accurately determine the outcome.


Advantages and Disadvantages

The technology used for Snickometer is relatively simple. It only requires a slow motion camera and good microphone which are available in any international cricket match. Thus the cost of the Snickometer is very low making it affordable to any country. Sometimes Snickometer takes a considerable amount of time to give the output. This is due to the synchronization issues of the video and the audio. But with the development of the technology the synchronization will be done automatically and the results will be available as soon as the incident occurs. 

Also the Snickometer only indicates that a contact happened. This contact may be between bat and ball, pad and ball or the bat and pad. It is up to the umpire to take the final decision. Thus this leads to inconclusive replays in some cases. But in Hot Spot it clearly shows the area the contact occurred.

Being a very simple and cheap technology it is surprising that, it is no longer used in UDRS. It can be combined with Hot Spot technology to make better judgments about LBW and Catch decisions. Out of the three technologies used in UDRS, Snickometer is the least controversial technology yet it is not even used in UDRS. And the most controversial technology is Hawk Eye which is made mandatory. The Hot Spot technology lies in between and it is made optional in UDRS. Just like humans no technology is hundred percent accurate. So always we have to use the technology wisely and improve the accuracy of decision making process to make the game of cricket more fair to both teams. 

Monday, July 9, 2012

Hotspot Technology







One of the main technology used in Umpire Decision Review System (UDRS) in cricket is the Hawk-Eye technology which tracks and predicts the path of the ball. Other main technology which is not mandatory under current cricketing laws is the Hot Spot technology. Hot Spot is the best available technology to establish the contact between the ball and the bat or pad.


History

Australia's Nine Networks owns this technology

Interestingly hot-spot technology was not intended to be used in cricket initially. It was expected to be used in military applications. These includes tracking jet-fighters,warships, tanks and satellites.This technology was founded by french scientist Nicholas Bion and later developed by other companies in paris. The Australian Nine Networks bought and adopted this technology. This technology is now offered by BBG Sports,an Australian company responsible for Snickometer in conjunction with Sky Sports.This technology was first used in the first ashes test match at the Gabba on 23 November 2006. The first usage of Hot Spot in the decision making process in cricket was in 2009 in South Africa.

Technology


Hot Spot uses infra-red cameras to capture images. There will be either two or four cameras at each ends of the ground. These cameras sense and measure the heat.When a collision happens either between bat and ball,bat and pad,pad and ball or ground and ball the temperature of those areas will be increased.Thus collided areas will be shown with a different color.


Advantages



Hot Spot has considerable advantages than other technologies used in Decision Review System.Hawk Eye is only used to predict the path of the ball.The only other technology available to detect collisions with the bat or pad is Snickometer or a very slow motion camera replay. But it only gives an idea about the time the collision happened and its amplitude. Thus no information about the point of contact can be obtained from Snickometer. But Hot Spot cameras gives the exact point of contact of the ball with the bat or pad. Thus Hot Spot is the best available technology to detect whether the ball hit the bat or the pad.

Disadvantages


The main disadvantage of this technology is its high cost. The cost of two camera set up is around 5000$ per day for two cameras. So if four cameras are used for a test match total price add up to 50000$. This is a huge amount of money and if we consider the limitation of number of reviews per innings for a team (which is currently two incorrect reviews) this cost can not be justified. Even when hawk-eye and other technologies were available at a much lower price some cricket boards still can not afford them due to financial reasons.


Also the number of Hot Spot cameras available are limited. These cameras are classified as a military device and needs a temporary export license from Australian Defense Department when used in another country. Also there are other government regulations that need to be satisfied.
Due to above reasons the usage of Hot Spot in Umpire Decision Review System is not mandatory.This technology was not used even in the ICC Cricket World Cup 2011.


Controversies


Although the inventors of Hot Spot claims very high accuracy, some of the decisions involving this technology have been controversial. There have been instances where Snickometer and other technologies confirms that there is a nick but ultimately Hot Spot did not show any evidence. Also during a test match between India and England there was a confident appeal for a caught behind. Although replays suggests that there may be some bat involved Hot Spot technology failed show any edges. Later Michael Vaughan tweeted that Laxman may have used Vaseline in his bat thus making it impossible to detect edges using Hot Spot technology.



Due to this criticism the inventors of hot spot technology carried out more tests on the reliability of the technology and now they have improved there technology and thus the accuracy of the system. Also they have proved that applying Vaseline or any other substance on the bat can not manipulate this technology. 

With new improvements this technology will be very useful for a fair game of cricket.But the problems with the cost and the unavailability of the devices have limited the usage of this in most cricket matches. Unless the price of this technology is reduced and the number of cameras available are increased this will not be part of the mandatory technologies needed in Umpire Decision Review System (UDRS).

Saturday, May 26, 2012

The Hawk Eye Technology



Technology has become an integral part of our lives. The use of technology in sports have also been increased. At first it was about broadcasting events worlwide.  But in the modern times technology is used to increase the fare-play in sports. Cricket has been one of the sports that uses technology extensively.  The first instance of using technology in cricket may be the third umpire concept which was first used in a test match in 1992. Although it was just a simple TV replay it helps a lot to take correct decisions on run outs and stumping and sometimes the legality of catches and to decide about boundaries.
But within the last few years more sophisticated technologies have been emerged and they are now been used in the game of cricket. One such technology is the hawk eye technology which is used in UDRS (Umpire Decision Review System).

History


Dr.Paul Hawkins
Hawk-Eye is a ball tracking system which is also used in other sports such as tennis. This technology is controlled by the Hawk-Eye Innovations Ltd which is a part of Sony Europe. Initially this was used as a broadcasting tool in cricket LBW decisions and now has become an important part in the decision making process in cricket matches.
The initial research for the Hawk-Eye technology began in 1999 by Dr.Paul Hawkins at Roke Manor Research Ltd. In the year 2001 channel 4 used this technology in broadcasting the Ashes series. In February 2002 this technology was first used in tennis broadcasting. In 2005 Hawk-Eye was permitted to be used as an officiating aid in tennis. This is mainly used to detect the line-calling decisions. In 2007 MCC world cricket committee announces that the Hawk-Eye will be used in the Decision Review System used in cricket.   In 2011 Hawk-Eye was used in a Cricket World Cup for the first time in history. Also there are plans to use Hawk-Eye in Soccer. This is still at the testing stages of FIFA and if the results are successful, this will be used in 2014 world cup.

Technology


Camera Placement in Tennis
The Hawk-Eye uses six high speed vision processing cameras positioned at different places in the ground along with two broadcast cameras to calculate the trajectory of the ball. Although there are 8 cameras available only 5 cameras are used depending on the side of the wicket that’s been used. In tennis there are around 10 cameras to track the ball. These cameras obtain a 3D visualization of the path of the ball after it’s been bowled. There will be two trajectories for each ball one for releasing the ball by the bowler up to pitching and another one for pitching the ball up to hitting the batsmen. Using this technology the speed of the ball, the swing of the ball from the bowler’s hand to the pitching point, the pitching point, the bounce of the ball, the spin or deviation of the ball can be obtained. Based on the second trajectory the expected path of the ball will be calculated and used to determine whether it will hit the stumps. This is widely used to decide LBW decisions.


Controversies


Camera Placement in Cricket
When technology is used in a sport there will be three very important things to consider. First it should be accurate. Then it should be fast enough so that the momentum of the game is not lost due to technology and finally it should be economically and technically affordable to use in normal games.
Hawk-eye is financially feasible. It is a low cost solution which only needs several cameras and some computers to do the calculation. Since cameras will be always available in an international sporting event the installing cost is very low. Also the time taken to calculate the path of the ball is short but sometimes this may damage the momentum of the game. This is one reason that the number of challenges by the players against the normal decisions taken by umpires or referees is limited. In cricket this is two reviews per team in each inning. Also in tennis the player will get two incorrect challenges per and three challenges in a tie break.
But the problem with the Hawk-eye is its accuracy. Although in tennis they have proved that it has an accuracy of 3.6mm in line calling decisions Hawk-Eye has failed to obtain the trust among players, referees and the general public. Also there are few instances in cricket that the decision given by the hawk-eye system is different than what most of the people expected.