Punch Bag Data Logging

I think it would be cool to put an accelerometer in a punch bag and calculate the force of punches and kicks, maybe to give a score Has anyone done this or anything like this? What accelerometer modules would people recommend for this? The ones I've looked at all seem to max out at about 6g, I'm not sure if this would be high enough (although I'm not Chuck Norris)

Matt, I'm looking at the same issue, but more from a kicking stand approach for TKD. There are a few 3 axis accelerometers which go up to 10-16 g. I just can't put my fingers on the info right now. I'll keep following and contributing to this thread. Doc

I'm looking at the same issue, but more from a kicking stand approach for TKD.

Cool. That's like a wooden pole with a target right? Could you use some sort of strain gauge on the bottom of the pole to detect the hits? Not sure how accurate that would be for measuring the actual force though.

There are a few 3 axis accelerometers which go up to 10-16 g. I just can't put my fingers on the info right now.

After I posted last night I had a look at some resistance force meters on sparkfun. They seem to be OK up-to 10KG weight (or 10 g) but they are only 5% accurate (under ideal conditions) and the datasheet said to expect around 25% accuracy. That is still plenty good enough to decide WHERE on the bag you hit/kicked though

(hit it's weak spot for MASSIVE DAMAGE! ).

I'm thinking that it might be possible to have them actually embedded in the canvas/filler of the bag, maybe 5-10cm or so under the surface, and use the change in resistance to detect pressure applied through the bag filler from the surface.

Having padding between the impact and the sensor could help survivability.

As far as accelerometers go, I think I'd have one either in the centre of the bag (In a project box buried in the filler) or attached to the bottom. I'm thinking of using a heavy bag, and I'm not sure I'd be-able to accelerate it much over 6 's anyway

I'm going to have more of a look around the web for similar projects and post back anything I find here.

Take a look at http://videos.analog...elopment-Board/

You can get one for $30 here: http://www.analog.co...ts/product.html

This board runs on 2 AA batteries and logs the data to an SD card. After your workout session you could put the SD card into your Netduino Plus and do whatever with the data.

Matt,

I'm looking at the same issue, but more from a kicking stand approach for TKD.

There are a few 3 axis accelerometers which go up to 10-16 g. I just can't put my fingers on the info right now.

I'll keep following and contributing to this thread.

Doc

Doc, I can't recall which hogu's my dojang bought for tournaments (I believe they are made by a company in Germany), but the ones we use are electronic with a force meter. They talk to the computer over a serial Bluetooth link.

IIRC the force sensing is done via a thin tube (closed at one end) which runs through the strike zone. The tube is then connected to the box which does force sensing and all the communication (one way).

I believe the force is measured in Joules (don't quote me on that though, its been a while).

Dan, let me know if you come across any information on the company that makes the equipment. I'll check it out.