On Wed, 01 Sep 2010 02:16:22 -0500, in comp.arch.embedded "Darth"
<theforce_vader@n_o_s_p_a_m.hotmail.com> wrote:

>>Darth wrote:
>>> Hey guys, first time posting here. I'm new to PC104. At uni we are
>building
>>> a mini electric race car and the team decided to use a PC104 to run
>>> everything including data acquisition (don't know why they opted for a
>>> ground up system when there were packages available for noobs)

Just wondering how this project turned out.

On Wed, 1 Sep 2010 07:44:23 -0700 (PDT), linnix
<me@linnix.info-for.us> wrote:

>
>> They've also purchased a 1GB CF card that inserts to the side of the PC104
>> board. There is one problem with this. In order to make it bootable he made
>> a floppy disk image onto the card and as a result the 1GB card now only
>> reads 1.44MB. Using a laptop HDD doesn't seem like a good idea because of
>> its moving parts and the vibrations from the car. Looking into a USB atm.
>
>That doesn't make sense.  CF should behave exactly like HDD, but
>slower.  I have many systems booting off 1G or 2G CF.  Even if FDD
>image is needed.  If could be a virtual drive image within the ext2(or
>3) file system.  Alternatively, a 1MB partition 1 and a 0.99G
>partition 2.  Can you ask him to explain the need for the FDD format?

Yup.  The person might have thought to make it like a bootable CD/DVD
where the boot image loads drivers to access the rest.  But that
shouldn't be necessary here.

George

> They've also purchased a 1GB CF card that inserts to the side of the PC104
> board. There is one problem with this. In order to make it bootable he made
> a floppy disk image onto the card and as a result the 1GB card now only
> reads 1.44MB. Using a laptop HDD doesn't seem like a good idea because of
> its moving parts and the vibrations from the car. Looking into a USB atm.

That doesn't make sense.  CF should behave exactly like HDD, but
slower.  I have many systems booting off 1G or 2G CF.  Even if FDD
image is needed.  If could be a virtual drive image within the ext2(or
3) file system.  Alternatively, a 1MB partition 1 and a 0.99G
partition 2.  Can you ask him to explain the need for the FDD format?

> Some good news. I dropped by the lab where all the electrical parts are
> been worked on. The electrical engineer showed me some of his latest work.
> At the moment he is using xPC Target to run run the motors. A lot of the
> system has been designed in Matlab.

I have no experience with Matlab but I suspect there's a _big_ difference
between running it on a lab PC and an embedded Celeron.


> They've also purchased a 1GB CF card that inserts to the side of the PC104
> board. There is one problem with this. In order to make it bootable he made
> a floppy disk image onto the card and as a result the 1GB card now only
> reads 1.44MB.

This guy sounds like he knows enough to be dangerous, I don't know what's
involved but the CF should be able to be properly formatted.


Keep us informed of progress!


Nial. 

> I want to make something clear.  Most CS students, undergrad,
> aren't quite as skilled as you probably need -- even near the
> time of graduation.  However, EE students (and certainly CE
> students) will likely have programming experience (micros are
> everywhere) that is close to what you are looking for.  And
> they often take some of the CS classes.  They will have the
> physics, electronics, and math backgrounds that will really
> help shorten the time and remove barriers as you get this
> project moving along.  The CS department students... maybe.
> Very maybe.  If you can find one, get a CE or an EE student.


I doubt that they'll find an undergraduate with the experience
needed to jump right in.

To the OP, you're better looking for a postgrad doing robotics research
or a lecturer (they're all profs over there aren't they?) who's
running a robotics team.

They will have most of the background you need and should be able
to advise on the best approach.

If this is a final year project then finishing it probably isn't critical
for a good result (at least this was the case when I was studying) as
long as it's written up properly. Make sure you've got your bits
completed properly.



Nial 

>Darth wrote:
>> Hey guys, first time posting here. I'm new to PC104. At uni we are
building
>> a mini electric race car and the team decided to use a PC104 to run
>> everything including data acquisition (don't know why they opted for a
>> ground up system when there were packages available for noobs)
>>
><snip -- already posted>
>
>Darth,
>
>This looks like a very cool project.  It is great that you are helping 
>out -- it appears that it is not your "baby," but nonetheless you are 
>offering assistance in your field of expertise.
>
>Your Universty computer department will probably point you in the 
>correct direction for resources in the embedded area -- keep us posted 
>on the progress.  Henry Ford once said that he did not necesarily know 
>about a field of expertise -- but he knew how to locate a person that 
>had it in a few minutes ... No worries.
>
>Stay cool.
>
>Don
>

Cheers guys and thanks Don for your encouragement. 

Some good news. I dropped by the lab where all the electrical parts are
been worked on. The electrical engineer showed me some of his latest work.
At the moment he is using xPC Target to run run the motors. A lot of the
system has been designed in Matlab. 

The stack of boards include a PC104, Power Supply board for PC104, 2 x I/O
boards (I think for all signals) and 2 x PWM boards. I mentioned to him
what people have posted here about one board not enough to run both motors
and he said that's why there is 2 PWM boards (9ch each). 

He said once he has finished all the modeling, he will put all matlab files
into once master file and change the format of it (somehow) so it can be
sent to the PC104. He was confident of this as he said he has sent small
programs to the PC104 and they seemed fine. 

They've also purchased a 1GB CF card that inserts to the side of the PC104
board. There is one problem with this. In order to make it bootable he made
a floppy disk image onto the card and as a result the 1GB card now only
reads 1.44MB. Using a laptop HDD doesn't seem like a good idea because of
its moving parts and the vibrations from the car. Looking into a USB atm.

So far, positives looks to be no need for embedded work if transferring the
Matlab file to PC104 works fine. 

	   
					
---------------------------------------		
Posted through http://www.EmbeddedRelated.com

Darth wrote:
> Hey guys, first time posting here. I'm new to PC104. At uni we are building
> a mini electric race car and the team decided to use a PC104 to run
> everything including data acquisition (don't know why they opted for a
> ground up system when there were packages available for noobs)
>
<snip -- already posted>

Darth,

This looks like a very cool project.  It is great that you are helping 
out -- it appears that it is not your "baby," but nonetheless you are 
offering assistance in your field of expertise.

Your Universty computer department will probably point you in the 
correct direction for resources in the embedded area -- keep us posted 
on the progress.  Henry Ford once said that he did not necesarily know 
about a field of expertise -- but he knew how to locate a person that 
had it in a few minutes ... No worries.

Stay cool.

Don

"Darth" <theforce_vader@n_o_s_p_a_m.hotmail.com> wrote in message 
news:mZKdnSaWLZUIHubRnZ2dnUVZ_uSdnZ2d@giganews.com...
> >Darth wrote:
>>
>>> Hey guys, first time posting here. I'm new to PC104. At uni we are
>>> building a mini electric race car and the team decided to use a PC104
> to
>>> run everything including data acquisition (don't know why they opted for
> a
>>> ground up system when there were packages available for noobs)
>>>
>>> We are using two brush less DC motors integrated with 2 inverters (DC to
> 3
>>> phase AC) and IGBT switch. The controller is:
>>> Advantech PC/104
>>> Model: PCM-3380F-M0A2E
>>> Processor: Celeron M 600MHz
>>>
>>> Lots of sensors such as wheel speed, motor speed/torque, temperature,
>>> current, voltage.
>>>
>>> My question here is that can we install a windows operating system such
> as
>>> XP in the PC/104 and and use that as our interface?
>>>
>>> Also, what software is needed for programming the board once the OS is
>>> installed? So far we've a stack of about 6 boards for motors, DAQ,
>>> inverters etc.
>>>
>>> The DAQ board has a 1GB card, is it possible to save data from sensors
> on
>>> the car to the 1GB card and transmit it simultaneiusly to a remote pc
>>> using Xbee?
>>>
>>> Appreciate any advice/suggestions as we are running short of time and
> have
>>> very limited knowledge of electronics. All parts have been purchased,
> its
>>> just that we have to make it work!
>>>
>>> Cheers
>>
>>I know you are still learning, but it is time to get real here. At the
>>present time it is sounding like the other members of your "team" have the
>
>>made the hardware choices and you are the software guy who will carry the
>
>>can for failure if it doesn't work. Weren't you in on the organisation and
>
>>selection of the hardware? Did the team do a proper evaluation prior to
>>selection of the hardware or did they just browse from a catalogue for
> bits
>>that could just plug together. Were the "noob" kits adequate or did they
>>have short-comings? If I were the tutor marking your efforts, I would want
>
>>to see some evidence that the choices you made had reasonable grounding
>>logic behind them.
>>
>>Forget running Windows (of any flavour) as that will most definitely be so
>
>>non-real time. Then sit down and really have a think and sketch out (in a
>
>>mind-mapping sort of way) what you really do need in the system
> (function-
>>wise). This diagram should include the user interactions with the system.
>
>>Until you have done this you cannot be sure you have all the assets
>>required. The system structure will start to show itself to you and you
> can
>>assign the resources properly to each part. Test the adequacy of the
> design
>>at all the steps to getting the best design structure.
>>
>>Then answer the safety questions. Like, if the processor is controlling
> the
>>motor speed, what have you in place preventing the vehicle running away at
>
>>an uncontrollable speed? I am sure you will start seeing more such
> questions
>>too. Re-arrange your structure to accommodate the ansers to the safety
>>questions and test adequacy of the design again.
>>
>>Consider that you may need to put in more than one processor (personally I
>
>>usually configure a minimum of one processor per actuator). The processing
>
>>load and safety aspects may be too much for one processor.
>>
>>Up-front design organisation is a more valuable commodity than even the
> most
>>expensive super-fast processor. Quite often my designs are achieved with a
>
>>collection of small, inexpensive, processors and peripherals. Those
> projects
>>that have a GUI interface will tend to be done such that the GUI is on a
>>Thin Client and has no way of impacting the normal safe operation of the
>>rest of the system.
>>
>>-- 
>>********************************************************************
>>Paul E. Bennett...............<email://Paul_E.Bennett@topmail.co.uk>
>>Forth based HIDECS Consultancy
>>Mob: +44 (0)7811-639972
>>Tel: +44 (0)1235-510979
>>Going Forth Safely ..... EBA. www.electric-boat-association.org.uk..
>>********************************************************************
>>
>>Thanks for your reply guys. I was actually helping out with another part
> of the car and have finished so thought I should lend a hand to the
> electrical side as they are struggling. I should also point out that we 
> are
> all mechanical and automotive students and apart from me, everyone else in
> the team are working in this project as their final year thesis, i.e.
> suspension, steering, chassis etc. The parts were ordered at the start of
> the year by the person in charge of the electrical stuff and we are over
> the budget atm as batteries were over $12,000. Honestly, not sure how/why
> they decided to take this route.
> This is most of the parts:
> *40Ah, 3.7V Battery Cell (lots)
> *PC104 Board
> *PC104 PWM
> *Voltage Transducer
> *Current Transducer
> *Power Supply PC104
> *IGBT
> *Resister
> *High Power Wire
> *Copper cable lug
> *Hall Effect Throttle Box
>
> So far, we've managed to get one motor spinning using matlab on a pc
> (simulink I think). Ideally, we would want both motors spinning while
> applying throttle (using a potentiometer).
>
> Can someone kindly tell me in the simplest form how we could achieve this?
> What I mean is how to make use of the PC104. Do we program it, or install 
> a
> OS and put the program in there? What programming software to use? How to
> integrate the sensors? what is real-time?
>
> I hope I'm making sense. Please correct me if something is out of context.
>
> Once again, really appreciate any help.

I think you're working at way too low a level. Before you even start to look 
at bits and pieces or flowcharts, you have to have a proper *project* plan 
in place, if you don't you'll just spin your wheels and fail to deliver 
anything. Unfortunately, IME academic institutions are often woefully 
deficient in that department, so you may want to find a friend or relly that 
works managing technical projects, who can help you through the process. You 
need to define an *achievable* objective, which may well be a lower target 
than you originally envisaged if you've lost time and are struggling with 
understanding. Then you need to identify the resources you need, which will 
include gaining familiarity with the technology. Then you need to break the 
work down into clear stages, with outcomes that you can manage and measure, 
and assign the tasks.

Given what you've described so far, I'd expect that setting up the platform 
and maybe prototyping some basic interfaces such as the motor drives may be 
as far as you can get. That's cool if it's reality, be up front with your 
supervisor and have them involved in the process. If s/he is dissatisfied 
with that, then go higher.

If you really do need to accelerate the process, then the correct approach 
is to engage the appropriate knowledgeable resources and review the project 
plan. Flogging yourself or others won't work.

I'd like a dollar for every uni (= college) project that I've seen go this 
way. The cause is almost always incompetent and negligent leadership by the 
institution. 

Paul E. Bennett wrote:
> Rob Gaddi wrote:
> 
> [%X]
> 
>>> Here is a link to a summary of the electrical system:
>>>
>>> http://img202.imageshack.us/img202/4190/electricalsystem.jpg
> 
> To those who have arrived late in the thread, I suggest you read back to the 
> OP's original post. You are asking some of the same questions that have 
> already been answered.
> 
> It is obvious the team have no real plan in place which is why they are 
> struggling but random suggestions of software are not really going to help. 
> They need on-the-spot assistance and hopefully they will find it in the 
> Computer Engineering department if the college runs Embedded Systems 
> Courses.
> 
> So far we do not fully appreciate their time-scale but it sounds like it is 
> fairly short. The car has to be big enough for the PC104 system to be seen 
> as a viable central controller with enough battery power to move it.
> 
> We are all going to struggle to help them at this remote distance so I hope 
> they find the people they need closer to their location.
> 

I've tried to give a little advice (I wouldn't say /random/ 
suggestions...).  But I thoroughly agree with your points here - the 
best help has to come from people who can see what they've got and talk 
to the team rather than from halfway around the world.

Robert Adsett wrote:
> On Aug 31, 2:38 pm, "Paul E. Bennett" <Paul_E.Benn...@topmail.co.uk>
> wrote:
>> David Brown wrote:
>>> You need to minimise the amount of programming you do - since none of
>>> your team are programmers, you won't be able to learn enough to do a
>>> good implementation of motor control in the time scope of your project.
>>>   Thus you need to buy in a ready-made motor controller.
>>> Look at this device:
>>> <http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MC3PHAC>
>>> If you can figure out a way to use this to control your motor(s), you
>>> can use the PC/104 system to provide the control signals to this chip,
>>> and to sample and record data if you want.  That way you might be able
>>> to salvage something out of your badly planned project.
>> I think you will find they already have that bit covered (check their list
>> and diagram).
> 
> It doesn't appear to include a motor controller.  Rather the pieces
> needed to make one.  I also think the Freescale device isn't complete
> enough for their needs.
> 
> Robert

I also failed to see any sign of a real motor controller - just points 
where their "controller" will connect to their drivers and sensors, and 
a quaint belief that a PC/104 board is a motor controller without the 
slightest idea how to implement it.

The MC3PHAC is a cheap and simple device that is easy to use.  I agree 
that it doesn't have all the features that such a car would need.  But a 
controller that would do everything they want would cost more than they 
can afford, and be more complex to use.  With the MC3PHAC, they have at 
least some chance of getting the car moving.