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Punching Power Meter

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#1 Guest_Dennis-Guest_*

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Posted 01 April 2005 - 05:35 PM

Hi there. I've been doing some research trying to come up with the best way to build a machine that measures the punching power of a boxer. What I want to do is have them hit a speedbag, and be able to get a numerical readout on a PC (the harder they hit the higher the number). This number by itself will have no meaning - it doesn't have to reflect PSI or anything like that - but will be accurate in relative terms to someone else hitting the speed bag. For example Mike hits the bag and gets a reading of 100, and then Bill hits the bag 3 times as hard he should get a reading of 300. I assume I would have to insert a pressure sensor inside the speedbag, and have it relay information to the Labjack, and subsequently to the PC. Once the bag is struck, I would like it to take a continuous sample over about a two second period and the number it ends up displaying would be the peak pressure/force measured over that period. Can anyone suggest a sensor that would do this an interface with the Labjack? Here is an example of what I am looking at doing (only with a much more simplistic design, and a PC interface)


Any advice would be appreciated.


#2 LabJack Support

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Posted 04 April 2005 - 11:23 AM

I think an accelerometer might be your best bet. They are inexpensive and easy to use. Analog.com has some good ones:


Freescale.com is another source. They also have good pressure sensors (the "integrated" series), but pressure seems more like you would just be measuring the deflection of the bag and this might not correlate that well with punch force.

By putting an accelerometer in the center (or perhaps on the back side surface) of the punching bag, you could easily get a plot of acceleration versus time. With some simple physics you could calculate lots of interesting data for a single punch, a group of punches, or an entire workout. You could do average, maximum, total, etc. for:


#3 Guest_Dennis_*

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Posted 04 April 2005 - 02:47 PM

So would a low g or high g accelerometer be more appropriate in this case?

#4 LabJack Support

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Posted 04 April 2005 - 02:58 PM

I have no idea how much acceleration a person can create on a punching bag. A safe bet is to start with a high-g sensor, and once you get a feel for the maximum acceleration you can select a final sensor which is better suited for that range. Another consideration is whether the bag can rotate. If it can rotate, you will need a 2-axis accelerometer, but if you can define a strike target at one spot on the bag you should be OK with a 1-axis accelerometer. You could use a 2- or 3-axis accelerometer to measure the vertical acceleration effect as the bag tilts, but I think you could just handle this in calculations if you need that much detail.

#5 Neal730

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Posted 02 October 2008 - 03:46 AM

Hi, i am an electrical apprentice, and have to design, and if possible produce, a project for my college course. I too am hoping to make a device capable of giving a visual representation of the force produced by a strike upon an object, and am considering using an accelerometer, that can be interfaced with a PC. I am currently undergoing the design process, and was hoping that perhaps i could find some help as to the best way to go about my project

#6 LabJack Support

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Posted 02 October 2008 - 09:18 AM

First, get a bag (I suspect lighter and stiffer is better since we are talking about measuring acceleration). Do some rough tests to estimate how much acceleration you expect. From the earlier topics, I would just define a specific punch spot on the bag and then use a 1-axis accelerometer. Now you can pick an accelerometer, connect it to a U3 or UE9, and take some measurements:


#7 GuitarFX

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Posted 09 January 2011 - 04:06 AM

The links does not work! Alternatively I know that some ac/meters have build-in digital-USB output...

#8 LabJack Support

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Posted 10 January 2011 - 12:48 PM

I fixed the links, but if Analog Devices changes them in the future just go to analog.com and select Products=>MEMS. Yes, some DMMs have a computer connection of some sort. In general a DMM will just have 1 channel and will be much slower than a LabJack.

#9 kevin franklin

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Posted 13 November 2011 - 03:12 AM

I am the inventor of StrikeMate designed to commercially measure punching power as a training aid. Please have a look at the technical overview on my web site to see how I concluded the best approach.I am happy to respond to all questions. www.strike-research.org

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