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-   -   Hi, I Need your Opinion on a new piece of test Equipment (http://www.Wattflyer.com/forums/showthread.php?t=73401)

Misa Rakic 03-21-2014 01:24 PM

Hi, I Need your Opinion on a new piece of test Equipment
 
1 Attachment(s)
Hello everyone, I value every ones Opinion here, that's why I am asking for your Thoughts, here are a few questions that I have, I will list them.

1. Would a multi power system tester be of interest to E Power Pilots (something like the one in the picture).

2. if yes, what would be a fair price for this type of testing Equipment, what would you be willing to pay for a multi function Power System tester.

3. what should the max thrust/amp/volt limit be on the tester.

4. please ask questions, I want your feed back, because this tester is being designed for your needs as well as mine.

Thank you for your time (especially Chellie).

CHELLIE 03-21-2014 10:30 PM

I Like it :$ Just my thoughts, at least 100 AMP range, 1 to 2 Kw Range and have some mounting taps to bolt it down to a bench for lager motors, I think clubs and the serious racer would love this test stand, Good luck to you on your Project, Chellie

solentlife 03-22-2014 03:07 AM

mmmmm

Description of what the item is to deliver.

How it works

What units will results be presented in

How to mount different items for test



I look at the picture and assume that this basically tests motor / prop combo's for RPM, Thrust.

Two factors spring to mind :

a) No airframe drag factors as the rig is slim and does not emulate draggy airframe behind prop.
b) Having to mount differing systems ... I test tractor and pusher props as well as EDF's ...

The humble kitchen digital scale, an LED tacho suffices for 90% of the tests I do ... a fishermans digital scale and webbing strap the other 10%.
I also get my results relevant to the installed airframe.

My testing is to find Flight results - not bench theoretical.

I do not mean to be rude ... but I think we are trying to re-invent the Mouse-Trap here ...

10 out of 10 for trying though and I am sure you will achieve what you look for.

Nigel

CHELLIE 03-22-2014 03:44 AM

Quote:

Originally Posted by solentlife (Post 943265)
mmmmm

Description of what the item is to deliver.

How it works

What units will results be presented in

How to mount different items for test



I look at the picture and assume that this basically tests motor / prop combo's for RPM, Thrust.

Two factors spring to mind :

a) No airframe drag factors as the rig is slim and does not emulate draggy airframe behind prop.
b) Having to mount differing systems ... I test tractor and pusher props as well as EDF's ...

The humble kitchen digital scale, an LED tacho suffices for 90% of the tests I do ... a fishermans digital scale and webbing strap the other 10%.
I also get my results relevant to the installed airframe.

My testing is to find Flight results - not bench theoretical.

I do not mean to be rude ... but I think we are trying to re-invent the Mouse-Trap here ...

10 out of 10 for trying though and I am sure you will achieve what you look for.

Nigel

Hi Nigel :ws: Your right, the info needs to be here too, he has it on another thread, here you go.

http://www.wattflyer.com/forums/showthread.php?t=73373

CHELLIE 03-22-2014 03:46 AM

http://www.wattflyer.com/forums/images/icons/icon1.gif Motor Master 5000 - rpm, thrust, power, etc. meter and tester
OK, so I finally got sick of testing my motors/esc/props on make-shift test stands. I decided to make something that will be as close to finished product as possible and hopefully, if there is any interest I could make it into an official product.

Without further ado, I present Motor Master 5000 (as in 5000g max thrust). Here are the specs:

1) Max voltage - 28V (0.1V resolution)
2) Max current - 50A (0.01A resolution)
3) Max load - 5000g (1g resolution, ~175oz)
4) Max RPM - 30000 (for measuring performance without the prop)
5) Size - 50 x 35 x 10 cm (LxHxW ~ 20"x14"x4")
6) Weight - 2kg (~ 4lbs)

Right now It's a standalone product and it displays data on the color LCD and also sends data via serial connection to the computer where you can further analyze it.

It sends data in ASCII or binary format (to be interpreted in the client application e.g. Processing which I will post soon too). Here is the sample ASCII output that can be pasted in Excel and then you can do with it as you please.

MotorMaster 5000 ver 1.0.1
VCC[mV] 4935 Cell K 0.186423 Offset 2083.6311 RAM 972
Servo RPM Vb[mV] I[mA] Thr[g] Cell Eff[g/W]
1000 0 11229 0 2.49 2097 0
1000 0 11229 0 2.49 2097 0
1050 382 11200 114 4.17 2106 3.43
1050 410 11200 105 3.98 2105 3.68
1100 804 11200 168 24.49 2215 13.56
1100 813 11200 168 25.42 2220 14.11
1150 1081 11200 265 45.93 2330 15.81
1150 1082 11200 259 46.12 2331 15.91
1200 1362 11168 441 70.16 2460 14.30
1200 1369 11170 413 71.10 2465 15.45
...


I would like it to (eventually) become an open source project but for now I will keep polishing it until it is ready for "public scrutiny" :)

Here are some pictures (sorry for the lighting) and I will soon be posting more and some videos too.

Oh and yeah, good news is it's also an Arduino! (Pro Mini which was even cheaper than the ATMega328p chip and you can easily replace it or use elsewhere in a dire need)

I'm open for suggestions and comments so please feel free to write.

Cheers,
Misa


Attached Thumbnails http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479
http://www.wattflyer.com/forums/atta...1&d=1395168479

solentlife 03-22-2014 04:11 AM

Quote:

1) Max voltage - 28V (0.1V resolution)
2) Max current - 50A (0.01A resolution)
3) Max load - 5000g (1g resolution, ~175oz)
4) Max RPM - 30000 (for measuring performance without the prop)
5) Size - 50 x 35 x 10 cm (LxHxW ~ 20"x14"x4")
6) Weight - 2kg (~ 4lbs)
mmmmmm

1) Max voltage - 28V (0.1V resolution) - OK good

2) Max current - 50A (0.01A resolution) - That's 50% of my models excluded then.

3) Max load - 5000g (1g resolution, ~175oz) - OK good

4) Max RPM - 30000 (for measuring performance without the prop) - That excludes a few of my models also.

5) Size - 50 x 35 x 10 cm (LxHxW ~ 20"x14"x4") - OK

6) Weight - 2kg (~ 4lbs) - Too light if what you are testing is as per 3) - needs bolting down ...

PC part ? Maybe for some - but for most - they only want to know they are getting thrust / amps suitable for the combo they are building.
The other factor as I said already is the lack of drag of the set-up. It will give static unimpeded thrust / airflow based results. Significantly different to installed airframe results.

Will it test EDF units ? That is a market that is ripe for sorting out. Props are covered so well by historical data available from even lowly Hobby King ! EDF's are another ball game though and even a small change on blade count or KV will have a serious effect on thrust / amps etc.

But of course we get back to uninstalled vs installed again ...

If OP wants to sell this - I reckon I'm a hard sell ... so c'mon convince me.

Honestly - I'm not trying to be rude or bad - I'm actually trying to make OP look at it and analyse what it is so he can develop a tool that can sell ...

Nigel

Misa Rakic 03-22-2014 12:55 PM

Quote:

Originally Posted by solentlife (Post 943270)
mmmmmm

1) Max voltage - 28V (0.1V resolution) - OK good

2) Max current - 50A (0.01A resolution) - That's 50% of my models excluded then.

3) Max load - 5000g (1g resolution, ~175oz) - OK good

4) Max RPM - 30000 (for measuring performance without the prop) - That excludes a few of my models also.

5) Size - 50 x 35 x 10 cm (LxHxW ~ 20"x14"x4") - OK

6) Weight - 2kg (~ 4lbs) - Too light if what you are testing is as per 3) - needs bolting down ...

PC part ? Maybe for some - but for most - they only want to know they are getting thrust / amps suitable for the combo they are building.
The other factor as I said already is the lack of drag of the set-up. It will give static unimpeded thrust / airflow based results. Significantly different to installed airframe results.

Will it test EDF units ? That is a market that is ripe for sorting out. Props are covered so well by historical data available from even lowly Hobby King ! EDF's are another ball game though and even a small change on blade count or KV will have a serious effect on thrust / amps etc.

But of course we get back to uninstalled vs installed again ...

If OP wants to sell this - I reckon I'm a hard sell ... so c'mon convince me.

Honestly - I'm not trying to be rude or bad - I'm actually trying to make OP look at it and analyse what it is so he can develop a tool that can sell ...

Nigel

Hey Nigel, you're not rude, just giving your opinion which is exactly what I was asking for. Here's what I think:

PC is not mandatory, you can read all the data from the screen, take a look.

As for the drag, Dr Kiwi was just arguing that there is too much of it in the "pull" configuration and that it should be pusher. No problem, you can mount it either way. Check you this link (http://www.rcgroups.com/forums/showthread.php?t=2126004) hope it's not a problem it's from a different forum.

Also, this is static thrust test; drag is less of a problem there. For actual dynamic (still test bench) tests you will need a wind tunnel. You are welcome to build that one :) until someone comes up with a product.

EDFs are possible, but that would require a different stand mounting bracket.

2) Current to 100A is not a problem
4) What is the actual max RPM you are looking for?
6) Absolutely too light (shipping needs to be low too, no) but there will be simple clamps to attach it to the end of the table (or screw down through he same hole if you prefer more permanent setup)

Look, of course everyone is making their own setup; obviously we all need the actual data. Simulations look great but it is nothing until you really test it. However it's a pain building a hardware which by the way is often less than professional and often flimsy (I had one myself and that is when I finally decided I want to have something sturdy and longer lasting :)).

As far reading data is concerned, you need to set your servo controller to specific throttle ($5-$10 for that, but what is the value actually in uS?, for that you need a "reader") and then read multiple values from multiple devices: RPM from (hopefully) optical sensor ($11-$25, must hold it properly) measure thrust on digital scales ($7-$15, depending on the setup there can be a systematic error due to small error in geometry), measure voltage, current, power (power meter $20 - $50, wait for the values to display, cheap ones circle through them due to basic LCD), write it down and finally calculate efficiency or whatever else you need. Yes, read the temperature ($10 - $15 still not sure how important that is but I like to know, some ESCs overheat well below their limit)

This is all *after* you spent hours building your own test stand which is more easy/difficult depending how handy one is...

Dollar amount wise just for the equipment you are well in the $60-$100 even without the stand. Even if you build it all for less than $99 you will still put *hours* of work into it...

Again, most of us on these forums *love* building things but I prefer to use up that time flying :)

And when you try to put it away, good luck with that since it was not really a concern when you started building it...

Alternative is: pay $99, put your motor/ESC/prop on click a button and read values, or open data in Excel and go deeper.

Please let me know your thoughts, this is how I see it.


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