Bicycle vibration monitoring

I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

On Dec 16, 5:44 pm, Ron wrote:
I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

I await Trevor's take ;-)

(You know th evalues will be different for every rider)

On Fri, 16 Dec 2011 17:44:30 -0800 (PST), Ron
wrote:

I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

Dear Ron,

You might see if the Specialized techs are willing to give you some
tips from what they did a few years ago--see page 11, where they
tested their damping:
http://www.specialized.com/OA_MEDIA/pdf/Witchcraft.pdf

Cheers,

Carl Fogel

"Ron" wrote in message
...
I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

Ron,
Lego makes an NXT programmable brick and has a 3-axis accelerometer sensor.
Total cost would be about $300. The programmable brick is about 4"x3"x2",
has internal battery power, and can be configured to store data for later
downloading to a PC or Mac for post-processing. Don't know if it's accurate
or sensitive enough for this application, but it's not much money, and great
fun for doing other things, too.
Kerry

On 17-12-2011 2:44, Ron wrote:
I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

Bruel & Kjaer has (or had) a handbook on the subject. Not muc h on
bicycles, but plenty on humans ;

The Oldenburg University had a bicycle department once:
http://lustaufzukunft.de/pivit/comfort/vibration.html
-
/Marten

info(apestaartje)m-gineering(punt)nl

In article
,
Ron wrote:

I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

You could geet an iPhone or an iPod Touch and run the Vibration app.
"Vibration is a true vibration spectrum analyzer using the built in
accelerometers inside the iPod Touch and the iPhone. It acquires and
displays time series data, optionally removes DC bias, applies a Hamming
window and performs an FFT on each channel to produce frequency spectra.
The 3-channel accelerometer has a sensitivity of approximately 0.02g and
a range of ±2g making the iPhone and iPod Touch sensitive enough to
analyze the vibration of most moving machinery."

On Dec 17, 1:41 pm, John White wrote:
In article
,



Ron wrote:
I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

You could geet an iPhone or an iPod Touch and run the Vibration app.
"Vibration is a true vibration spectrum analyzer using the built in
accelerometers inside the iPod Touch and the iPhone. It acquires and
displays time series data, optionally removes DC bias, applies a Hamming
window and performs an FFT on each channel to produce frequency spectra.
The 3-channel accelerometer has a sensitivity of approximately 0.02g and
a range of ±2g making the iPhone and iPod Touch sensitive enough to
analyze the vibration of most moving machinery."

They've sure come a long way from the original Sony Walkman.

On Sat, 17 Dec 2011 16:41:54 -0500
John White wrote:

You could geet an iPhone or an iPod Touch and run the Vibration app.
"Vibration is a true vibration spectrum analyzer using the built in
accelerometers inside the iPod Touch and the iPhone. It acquires and
displays time series data, optionally removes DC bias, applies a Hamming
window and performs an FFT on each channel to produce frequency spectra.
The 3-channel accelerometer has a sensitivity of approximately 0.02g and
a range of ±2g making the iPhone and iPod Touch sensitive enough to
analyze the vibration of most moving machinery."

I've tried using the accelerometer recording app on my Android phone (at
1/5th the cost of iPhone), but the inherent noise in the sensor was
greater than the signal I was looking for. (Bike's steering movement
and lean angle.)

By all means try it if you've already got an iPhone, maybe Apple fit
better accelerometers than Huawei.


Mike

On 18/12/11 08:41, John White wrote:
In article
,
wrote:

I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

You could geet an iPhone or an iPod Touch and run the Vibration app.
"Vibration is a true vibration spectrum analyzer using the built in
accelerometers inside the iPod Touch and the iPhone. It acquires and
displays time series data, optionally removes DC bias, applies a Hamming
window and performs an FFT on each channel to produce frequency spectra.
The 3-channel accelerometer has a sensitivity of approximately 0.02g and
a range of ±2g making the iPhone and iPod Touch sensitive enough to
analyze the vibration of most moving machinery."

Any idea what the sample rate and precision is?

--
JS.

In article ,
James wrote:

On 18/12/11 08:41, John White wrote:
In article
,
wrote:

I've been itching to do a personal project for sometime, for some
fun.

So I'd like to just get a perspective on what the RMS values of
acceleration (aka vibration) are on a bicycle, at key locations - say
the frame, handlebar etc. So the task would be to get appropriate
triaxial accelerometer, a DAS/power supply and a computer. I would
prefer that the accelerometer be digital and relay data to the DAS
which can dave the data for post processing on the computer. But if
the cost is going to go up for that, an analog sensor would be also
fine. Perhaps I can then look into designing my own circuit on a board
as well to process the signal. I'd like the sensor to be adhesive
mounted for flexibility (instead of drilling holes in my bicycle!).

So I have very rough ideas but no concrete specifications. I guess the
challenge is to understand what kind of frequencies are typically seen
in an application like this. Having a range, I can look for a sensor.

Could you help specify what is the best way I could go about doing
this and what kind of equipment would help me most? What kind of costs
am I looking at? Let me know what information you would need.

You could geet an iPhone or an iPod Touch and run the Vibration app.
"Vibration is a true vibration spectrum analyzer using the built in
accelerometers inside the iPod Touch and the iPhone. It acquires and
displays time series data, optionally removes DC bias, applies a Hamming
window and performs an FFT on each channel to produce frequency spectra.
The 3-channel accelerometer has a sensitivity of approximately 0.02g and
a range of ±2g making the iPhone and iPod Touch sensitive enough to
analyze the vibration of most moving machinery."

Any idea what the sample rate and precision is?

See http://itunes.apple.com/us/app/vibra...301097580?mt=8