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Making the Memsense Mag3 IMU Wireless?

I am trying to figure out a way to wirelessly transmit the output of a memsense Mag3 Inertial Measurement Unit to a receiver up to 30 feet away, while maintaining the smallest possible footprint on the transmitting end. I was originally thinking a "Mote" would be the answer, but motes don't seem to be able to transmit enough data fast enough. I don't know if the product or technology will be wifi, bluetooth, cellular, etc. but I would really appreciate any advice or someone who can point me in the right direction to find the answer or suggest a product or technology that could interface with the Mag3 and transmit its output wirelessly to a receiver.

Here is a link to the Mag3 datasheet:

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Thanks in advance,

Matt

Reply to
Matt
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What is the data rate (and so the band width) requirement of the 30 feet transmission?

How much this Mag3 costs?

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Reply to
<many gates>

Thanks for the reply Many. The bandwidth as listed on the datasheet is 50hz. Do you think you have a solution?

The Mag3 runs about $930.

Matt.

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Reply to
Matt

Matt,

What I understand from the doc. is that unit provides analog outputs. So I assume you need to digitize the analog signals for the transmission. Depending on your sampling rate, number of channels, Analog to Digital Conversion Reolution and error check/correction mechanism for your digital transmission you may end up something like the following equation for your bandwidth (bits/sec) requirement (50Hz) x (2) x (number of channels) x (ADC resolution + Start/Stop+CRC) You should find this figure before searching 30ft transmission.

Regards,

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Reply to
<many gates>

Many,

Yeah, I will definitely need an ADC. I am not sure if I am able to solve that equation at this point, maybe you can help me. I want a tranceiver that can transmit the Mag3 output at full capacity. Couldn't I output everything over one channel? As far as the ADC resolution and Start/Stop and CRC I don't know these values yet, since I haven't selected the ADC. Thanks for your help.

Matt

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Reply to
Matt

This really looks like a neat part.

Yes, you can transmit everything over a single channel.

However, This means all data will be sent serially, One after the other. If you were to have an 12 bit ADC, as mentioned : (50Hz) x (2) x (number of channels) x (ADC resolution + Start/Stop+CRC)

Thats a lot of bits to send in 20 millaseconds (50 Hz)

Also how small is your "small footprint" ?

I think the analog output of each channel can drive a voltage-to-freq converter. Multiple PWM transmitter and receiver circuits could be used to decode each channel.

Build one and repeat. Adjust freq for each channel.

google for voltage-to-frequency converters.

hamilton

Reply to
hamilton

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