I need someone to design a simple PCB for me

Discussion in 'The Projects Forum' started by Joe Black, Jan 5, 2016.

  1. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    I am working on a project to build peristaltic pumps and I have a need for someone to design a PCB to run the machine. It will have a small Step motor, like a NEMA 17. The basic functions will be On/Off, LCD Display, it will have a pneumatic foot switch, it needs to calculate the Rate being pumped and the Total volume based on the speed of the motor and display those numbers, control the speed of the motor, which will set the volume rate. Obviously, there are a number of details one would need to design this, but the PCB is the area I have no real knowledge to design. This would be the roadblock for my project, so I wanted to attack it first. I will be able to provide all of the specs needed. This isn't a rush issue. I am reverse engineering a pump, but the pumps I have have way too many functions on them and items that I do not need. I saw a YouTube video of a PCB a guy built using an Arduino board to control and display it. I cannot us an Arduino board in my machine, but it tells me this shouldn't be too difficult for someone who does this work, but I just don't know whom that would be. If I can get this done reasonably, we will build these to sell.

    Again, simple functions:
    On/Off switch (Power)
    Drive a Stepper Motor and control the RPMs
    Use a pneumatic switch and air bellows to operate the motor Off and On (like the ones in Spas)
    Count RPMs
    Calculate Dispensing Rate based on the RPMs
    Count Total Volume dispensed
    Display Rate being dispensed, and Total Volume dispensed.
    Prime Button (runs the pump at the highest RPMs to prime the tubing)
    Run a small cooling fan
    Reset button or Clear the system for a new job.
    I would also need some code written to run it. It may also, be good to have a way to fine tune or calibrate the machine in house, but not accessible to the customer, but that is a secondary option.

    Will be powered by a Transformer producing 12 DCV from variable ACV input. (90 - 240 AVC). Standard shelf product. All of the components will be Std off the shelf items. These are the same type machines used in labs everywhere. Once I have a design, I'm sure I can get these made most anywhere, but a referral for the production of the PCBs would be helpful as well.

    Thank you, Joe
     
  2. nerdegutta

    Moderator

    Dec 15, 2009
    2,517
    785
    Hi Joe, and welcome to AAC.

    In order to design a PCB, you'll need to design a schematic diagram. But before that, it is sometimes nice to make a block diagram. This will let you define what you want to do.

    The schematic diagram will give you a list of the components you need, and how they all are connected. The PCB is "only" placements of the components, but I'll guess you know that. It would be nice if you revealed your level of expertise.

    Have you installed a PCB software on you computer? I like to use EagleCAD. Some members here like to use KiCAD, DipTrace or ExpressPCB.

    If you make a schematic diagram over what you think will work, and post it here, you will be guided in the right directions.
     
  3. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    Thank you, nerdegutta. I actually, have No electronic experience. And, No I din't know that PCB meant the placement of the components. What I need is someone to do the schematic so I can get a board made. All I can really do is a basic block drawing of the parts in the machine (pump) and list the functions I need it to perform. I chose this site hoping to find someone who could do this for me. If I'm in the wrong place, I apologize. All I've turned up so far are people who will build the boards when I get a schematic for them. i need the schematic designed for me. I don't know where to begin, otherwise. Joe
     
  4. nerdegutta

    Moderator

    Dec 15, 2009
    2,517
    785
    OK, I see.

    Try to draw a detailed block diagram, covering the complete project, so the members know what to do / draw. Please also describe the software you need. Preferably with a flowchart. If you think of some kind of menu, flowchart it. If this is a long term project, take your time and be specific and detailed. I don't think this can be made in a hurry. :)
     
  5. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    OK, I think I can do that. Yes, this is a Long term project. It will be a year at least before I could begin building these my self.

    Should I just come back to this post or just start a new one, and in what category?

    Thanks for the help.

    Joe
     
  6. nerdegutta

    Moderator

    Dec 15, 2009
    2,517
    785
    I've moved the thread to the Projects forum.

    If you should start a new thread or continue this? It depends on when you will be back. If weeks go by, start a new thread, with a link to this. Then everybody has the opportunity to get up to speed. :)
     
  7. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    Very good! Thanks
     
  8. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    5,699
    905
    What do you plan to pay per hour for electronic design and PCB design work? Any business references?

    John
     
  9. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    Good question! First, yes we can supply plenty of business references. We've been in business as B&B for 8+ years and our previous company for >30 yrs.

    Again, not having any real knowledge of the process and work, I would need some kind of Ball Park as to the costs I may experience in this process. Like most people not in the business, I probably overly simplify things and other peoples work. I am figuring that this should be a rather simple task for someone that knows what they are doing. I have a friend who is a computer engineer and a couple of my son's college buds from GA Tech are electrical engineers. I probably should get some advice on how difficult this can be. I'm not as worried about the code as I know a slew of programmers, but, as I mentioned before, I know squat about designing a circuit board to run this pump. That said, is it fair to ask for quotes once I've submitted my basic plan? "By the hour" scares me. Cost + makes me feel a bit better. I just have no idea what it is I'm getting involved in, other than I saw a YouTube video where a guy did exactly what I needed done using a simple Arduino processor board. I've had some boards made for an endoscopic camera we built, but someone had already designed the board and we just had a company in FL to make them for is. I could not find who drew the schematics. We no longer make those cameras and the original owners are long gone.

    So, is it Kosher to submit my basic drawing and plan and get some quotes first?
     
  10. hp1729

    Well-Known Member

    Nov 23, 2015
    1,957
    219
    There are not such things on the market already?
     
  11. BR-549

    Well-Known Member

    Sep 22, 2013
    2,004
    394
    What will be the maximum lift required?

    And accuracy of flow rate?
     
  12. Picbuster

    Member

    Dec 2, 2013
    374
    50
    This is a complex project with lots of if then else situations and human interface, how to detect and handle errors and safety issues, EMC and EC marking. It will take al least 8-12 working weeks to have a working proto. But if it remains in lab used by one person (designer) you can skip a lot.
     
  13. BR-549

    Well-Known Member

    Sep 22, 2013
    2,004
    394
    Working in several labs over the years, Unless you understand and can build it yourself, I don't think you can compete with the existing market. Have you checked existing prices for similar equipment?

    I have done many site surveys for discharge permits for the EPA and state epas.

    These are flow weighted sample surveys lasting from one week to three months.

    A processor controlled peristaltic pump, temperature controlled container(for samples), and strip chart flow recorder. Plus a air bubbler and air collared weir plate for flow measurement. All powered with 12 v battery. This whole assembly could be placed into a manhole and hung there. We could sample 15-20 ft. heads. Some wet wells are very deep.

    Of course nowadays the equipment would be smaller and all digital and results recorded on a thumb drive.

    With your set up......available power, and non potability, should cost you less, but will still be expensive.

    Just the word "lab" makes the lab equipment business a racket.
     
  14. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    it varies with the speed of the pump, but being a peristaltic pump it is rather consistent. I can get the flow from one of our current pumps, but to be totally accurate, I'd need to build one of our own and measure the flow rate. The current pump I am using does 550 ml/minute at 300 RMPs (normally used) and 1100 ml/minute at 600 RMPs (max speed). Very consistent. The counter is just a back-up and only needs to be consistent. This will be a medical device and the Doc watched the IV bag more than the display. The display is more so they can set an approximate rate.
     
  15. wayneh

    Expert

    Sep 9, 2010
    12,145
    3,055
    No offense but I think you're way out of your league. As BR-549 noted, there are many commercial devices available to choose from. I've used several myself. I wouldn't dream of reinventing such a thing.

    Add on to that a medical requirement and it's way beyond a DIY project. The hurdles in between any of those fine commercial products and a classification as a medical device are daunting. Lots of paperwork, testing, expense, lawyers and so on. It's why a medical pump costs 10 times what a lab pump costs. It may be the same pump, but it's certified.

    IV pumps already exist. Why reinvent one?
     
  16. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    Actually, this will me a medical device. We will have it tested by a lab for IEC 60601-1-2 (FDA 510K requirement and CE), and possibly TUV/UL certification. All of the electronic parts otherwise shouldn't be a problem there. My two Chinese pumps passed fine. There may be a "Shelf Product" out there, but I don't really know where to look for it. These are really, basic functions that the Lab machines all have. Due to the FDA testing requirements, none of the lab device manufacturers have the proper certification, so I'm back to square one again. That's why we are looking to build our own.
     
  17. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    Actually, this will me a medical device. That makes it even more expensive. I understand everyone's' concerns, but as far as the device itself, I know what I am doing and have the ability and knowledge to put this altogether. The missing piece is the board to operate it. Everything else, except for the case itself, are off-the-shelf items. I just need the PCB to run it.
     
  18. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    There is, for lab use, but this will have to be approved for Medical use. And, that is a totally different realm. Somewhat like the difference in aircraft devices for General Aircraft and and devices for NASA. The General Aircraft parts may work well for NASA, but could not be certified by NASA standards. The manufacturer would have to be certified to make them in advance and most shops aren't going to do that unless they are going to make a lot of those type parts. The market for these pumps in the medical field is small. We are small, so we can pull it off, I believe. I just need some help on one part of the project.
     
  19. Picbuster

    Member

    Dec 2, 2013
    374
    50
    Ball park figure for the design and proto cost without all the certification will be mimimum150000 Euro.
    User manual 3 weeks.
    Description of the complete unit inclusive software 3 a 4 weeks.
    Certification for medical usage will be above the 200000 euro
    EMC and Ce at minimum 6000 euro.
    Corrections 1 week.
    I do agree with wayneh and the others; If no business plan( market) is justifying this project stay away don't burn your back site unless you have a unlimited source of money and like spending it.
    Again do not see this as offending or pissing it off . I am 40 years designing measure and control equipment for government and major companies and I have being lucky that I was surrounded by good people with knowledge to advice and discuss the risks.
    I can ensure that they saved our ass more than once.
     
  20. Joe Black

    Thread Starter Member

    Jan 5, 2016
    48
    1
    No offense, but it sounds like you are out of your expertise. If there were many devices of this nature out there, I rather doubt I'd be trying to do this. You are preaching to the choir! I fully understand all of what is involved, but this is not a one-off DYI project. We will manufacture these devices. I have built endoscopic cameras used in surgery, and once you have the parts, it's like Tinker Toys assembling them. Been there done that. What I do not have the expertise in is building a PCB to run it. I'm a bit taken back at the lack of expertise I find on this site to design a simple PC board. A guy built one on YouTube with an Arduino board and it did exactly what I needed. I cannot use Arduino parts, but maybe I should be talking to "Instructables" and YouTube people. And, what makes yo think it's an IV pump? You can't use a peristaltic pump for IV use. You'd kill someone. And, as a business man, why would I buy retail and try to sell it for a profit? There is no future in that! And a ten fold increase from Lab to Medical is a bit of exaggeration. We'd love to get that kind of margin, but we can't. But, yes, due to the testing, certifications, arcane government regulation and abusive Federal Taxes, Yes, medical stuff does cost a lot more, it's just there is not that much profit left in them as one would like to think.
     
Loading...