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Tennis Court Speed Measurement

  1. Feb 3, 2012 #1
    Hello everyone!

    I'm part of a student team currently developing a piece of equipment to measure the speed of tennis courts. The brief for the project is given below;

    Sports Labs Ltd is a consultancy practice specialising in synthetic surfaced sports facilities design, procurement, project management and testing services. As part of their work to measure the pace of tennis courts, they currently sub-contract work utilising a Wassing sestee << Link removed by Moderator >> device. The sestee is used in conjunction with a compressed air powered ball cannon.

    The equipment utilises two pairs of laser arrays to calculate the speed and trajectory of the ball. This set-up has a number of issues: the time to assemble and calibrate the unit is considerable, it consists of a number of separate parts, and it is very large and bulky meaning transport is problematic.

    A prototype device has been constructed that is designed to be more practical and easier to transport than the existing Wassing device. The aim of this project is to review its current status, then progress the embodiment and mechanical detailing of the product so that it can be assembled and operated robustly. This work will also involve optimising the electronics and mechatronics of the laser arrays to verify that that device is giving accurate readings. Finally, the product packaging should be addressed so that it can be transported and used by Sports Labs staff.

    The prototype mentioned in the brief is rubbish and is to be redesigned. The main area we are having trouble in is the alignment of the laser arrays. Currently the Wassing device uses 4 arrays of single red lasers, each of which is aligned with its own receiver diode which you might imagine, are difficult to align with each other. The idea is that as the tennis ball cuts the laser beams, it activates the receiving diodes. There are 2 arrays before, and 2 after the ball bounces on the court to measure velocity before and after and also the trajectory of the ball.

    We have decided to replace the normal red lasers with line generating lasers which will minimise the number needed. Then, with the use of lenses, collimating the laser beam in to a parallel sheet of light for the tennis ball to cut.

    http://img339.imageshack.us/img339/9415/lasersheet.jpg [Broken]

    Hopefully the image above gives you a better idea.

    Can anyone see any problems we may have with this setup?
    And if not, can anyone recommend a good catalogue to buy lenses and lasers from?

    Any input appreciated,

    Last edited by a moderator: May 5, 2017
  2. jcsd
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