Help with the OpenFES Project

[bikeracer]

Hey disco01,

I havent seen an update from matt in a while, so not sure how his project is coming along. I'm also working on a FES cycling project which i am determined to finish before its two year aniversary in april 2009. Its almost there I'm just having issues with time / interest / procrastination.

BR

[Nightmare]

I dont think its really going to tell you a lot about the super technical stuff....

[bikeracer]

Nightmare,

What super technical stuff are you referring to?

FES in its basic form is fairly simple in that it just requires a mono-phasic(or bi-phasic) electrical pulse at the correct pulse width (duration), frequency and power (volts / milliamps) to stim the muscle group.

I have a fully working 6 channel FES unit built, but admittedly it is version 4 and I still keep fiddling rater than just locking down the specification. I have also built and tested the ergometer (set of pedals). I have also written the control program for the FES unit.

I just need to get my ass in gear and try it out, which is proving more of a challenge than designing the thing in the first place!!

I suspect it will not work first time out, and in some ways this is probably why I have lost a little interest - the fear of failing - but not completing it is just as bad so I will get it done in the near future.

BR

[mattblan]

What's up! Forgive me for not posting, I barely survived finals. The OpenFES project is alive and well. We are looking at adding a new engineer during the break. This semester is the first one with an advisor, so my grade is actually on the line now. We have been blessed with a few more donations. Most notably, a medical grade power supply for our FES unit. I am taking a few days off for the holidays, but I will post some schematics soon.

Bikeracer, have you looked into Labview? It makes data aquisition and control extremely easy. Unfortunately, it is not open source so we cannot use it. I might be able to put you in touch with someone who can get you a copy

We will be done with computer control of the stackable channel FES unit by the end of Spring '09 Semester. The power supply we use can handle up to 10 x 1 channel modules and a decent low power CPU at the same time.

Happy Holidays!

Matt

[bikeracer]

Hey Matt good to see you back!

That Labview looks like a great bit of kit but way to complicated for my simple setup, so I will stick with my home brew software - thanks for the offer of the trial (ahem ) copy of the software.

Have a good new year,

BR

[mattblan]

Few updates:

I put up a flicker page here with a few photos of the dev board, power supply, and embedded system. The single channel FES proof of concept is very close to being complete. We just need to drop in a missing IC and solder a capacitor and we will be ready to turn it on. I have decided to ditch the chain driven system on the Powertrainer for a couple of electic motors. Using these motors, we can adjust resistance, detect user torque, and even passively pedal the bike if neccessary. We are sizing up the bike tomorrow to see exactly which motors we want to go with.

On the system level, I have been trying like crazy to get the OpenFES Linux distribution compiled. I thought I had solved all of the issues last night, but I woke up to a broken build. I started the build again on my laptop, only to have the partition run out of space. When I get it done, I will upload it to the at91sam9261 development board and set to work on data aquisition and control.

Here is the dev board as of 1-5-09. It's just a proof of concept, so the controls are analog (the giant potentiometers you see). Once we prove it works, we will replace the analog pots with digital, add serial communication and a few other goodies, then send it off to be fabricated.

[bikeracer]

Nice job Matt, its good to get the first one built!

I will post a picture of the circuit I have working, good to see its not just mine that looks a little cluttered!!

BR

[bikeracer]

For those interested in pictures of wires and stuff!!

Power supply. USB interface and Stim Channels 1-3 (lots of wires!!)




Stim Channels 4-6

[mattblan]

Updates 3/2/09:

-Wiki has moved to http://www.openfes.org
-Microcontroller Schematics are being uploaded.
-FES Unit Schematic is being finalized.
-CPLD's for FES Control Logic are arriving this week.
-User Interface Shell is completed.
-Optical Encoder (to determine crank cangle, RPM, etc) is being ordered this week.

The first project presentations will be held middle of May. All Video and Documentation will be available on the website shortly thereafter.

Matt

[edqman]

I'm a C7 quad. I live in Northern Ca and a Sac State Grad. Just recently injured February 17, 09. I am interested in talking to you about your machine. Can you email me? edqman@yahoo.com. Thanks

[mattblan]

Email sent, looks like we are neighbors =)

We finished our initial Bandit prototype and we will be giving a presentation Tuesday night at CSU Sacramento. Video will be posted shortly after and we will be updating our wiki with more details.

Basically here's what we accomplished so far:

1. Designed a PCB single channel TENS Circuit with digitally controllable pulse width and current amplitude while providing feedback of actual current amplitude attained.

2. Mounted a rotary encoder to a passive upper/lower body trainer (SciFit) to obtain crank angle and calculate RPM.

3. Designed an algorithm that takes current RPM and sends firing commands to 6 TENS circuits to maintain angular velocity.

4. Designed a simple socket graph that displays current RPM against the pulse count for each muscle group in real time.

Matt

[kevinj1]

I too, would be interested in trying your machine. I'm a C5 quad that is fairly knowledgable in FES
www.kevinjmullin.com
that is me

you can email me at kjmullin@yahoo.com

thanks,
Kevin

[mattblan]

Thanks Kevin. I really liked your site and I sent you an email. For everyone else, Summer is here again and there are many talented people who may be coming up on some free time. If you are looking for a worthwhile cause, why not donate your expertise to the OpenFES project?? =)

We completed our prototype FES cycle and we are looking to make a bunch of improvements in the coming months. In the winter, our major engineering tasks will be adding two DC motors, shrinking and fabricating our digitally controlled 8-channel TENS unit, and enhancing the user interface.

A separate engineering team has plans to incorporate brain machine interface (BMI) technology to provide a rider neuro control of the TENS unit while competing in a simulated racing environment. In other words, they want to use brain feedback to pedal the bike instead of letting the computer algorithm do all the work.

If anyone is interested in Google Android, I plan on redesigning the OS using the Android SDK over the Summer and I would love to get a few Java guys on the UI team!

I will update openfes.googlecode.com as soon as I can so that everyone can see exactly what we have, where we are going, and how exactly we plan to get there. Feel free to leave comments on the site.

Regards,

Matt

[w23s]

hi matt,
i know your no longer interested in fes rowing i'm and currently taking part in a f.e.s rowing trial in the u.k. if its any interest i can put you in touch with the guy leading the project or if you need any other info i'd be happy to help.

[bradzz]

If anyone is interested in Google Android, I plan on redesigning the OS using the Android SDK over the Summer and I would love to get a few Java guys on the UI team!
Regards,

Matt

Interested in helping, am a java coder and embedded systems know how.

http://developer.apple.com/ipod/apply.html