New Technics SP10 motor controller specification

[Steerpike]

One or two more pictures & some more maths theory just updated.

The maths and measurements might be over the top for some, but I'm putting it all in, in case there's anyone who wants to do this sort of thing for OTHER models. They can then do the necessary calculations and tests for any motor.

[Steerpike]

I've just finished measuring the torque/voltage characteristic of the motor. It's rather satisfying when you get such a straight line, directly from the measurements! No curve fitting required.

[brianco]

STEERPIKE,

I have tried to mail you but, sensibly, your mail is "off"!

As you are doing such hard and time consuming work of interest to many of us, I am prepared to try and find you a correct platter for a Mk 11P as there are many here which have been robbed for other spares.


But some decent UK or other member who reads this may already have one which he will donate so that you have a 'proper' unit on which to base your research...ANYONE OUT THERE???

[Shaun]

I have a spare platter and housing (of which the original finish has been stripped). Steerpike, if you're interested drop me a PM.

[brianco]

Shaun:

Well, I think that is very kind, but then with Shaun as a name it is just what I wopuld expect! Good on you!!

[Shaun]

Originally posted by brianco
Shaun:

Well, I think that is very kind, but then with Shaun as a name it is just what I wopuld expect! Good on you!!

Hehe

Shaun/Sean, I presume...?

[brianco]

[Steerpike]

That is very magnanimous of you Shaun! And thanks Brianco for the happy thoughts.

(Cerainly getting something from Cape Town is easier and less prone to loss/damage than from overseas)

Something is wrong with the board mesaging service. My setting for emailing me are 'yes, allowed'. But I cannot message Shaun, just as Brianco you couldn't message me.

I will set an email link on my home page - in the SP10 writeup - later today. (I don't want to post an email address here in this message since once it's here, I cannot edit or erase it, if I need to)

[Steerpike]

Yay! Finally all the electromechanical constants for the motor measured

Ra = 12.8 Ohm
La = 0.038 Henry
B = 0.0031468 Nm/rad/sec
J = 0.0457 kg.m^2
K1 = 0.02963 Nm/v
Kbe = 17.99 v/rad/sec
kt = 0.379264 Nm/amp

I doubt these were ever published, so no way to see how close my motor matches the expected manufacturing tolerance. It's not particularly important, since the feedback loop vastly reduces the impact of variabilty in the 'model' on the final performance.

I think my pvt messging ought to work now; I set 'hide email address' to NO, and it seems it won't actually reveal my email address, but will allow messaging.Send me a private email message

[Shaun]

I am very impressed by how scientific your approach is, Steerpike. It only bodes well for the final outcome.

I have sent you a PM. I see that your email is also now enabled.