Ultimate MSXR 3/4DOF

[Riton]

mini j7
http://support-omron.fr/pdf/J7%20Manuel ... sation.pdf
I have 0 acceleration / deceleration is the best setting.
add acceleration / deceleration degrades performance.

yes motors are in Delta .

15 RPM, I test tomorrow, but this is not the solution!
I'd like to test with 0 dead zone to see if the performance
is different.

it's hard as a change? can you provide on the AMC 128?
you could put the dead zone that starts at 0.
0 no dead zone at all


on the servo motor, there is no dead area on the sensor

[tronicgr]

I'll be doing something even better. I'll be using a little bit of fuzzy logic. What is does, is to vary the rate of the PID along the speed variation. I'll include this for testing in the next firmware as well (in a few days).

Its not hard to add 0 deadzone. But your motor minimum "step" should not overlap it as then it will keep trying to seek the position.

[Riton]

my english is bad, I am not understanding...

[Riton]

ah yes I can be understood ...

if the engine continues to seek the position, it maintains a current and therefore keeping the load on the position.

in the dead zone, the current is not maintained, so the load drives the motor until the position value 5%.

at this moment it was the load on the position ...

True?

as long as there is no load on the engine or when the engine maintains the charge, there is no problem with the dead area I think.

the engine at stop or so, but the charge is maintained by the gearbox with wheel

but with a load, the engine must remain different power to hold the load.

and the dead zone is cut for a while.
this time increases the reaction time of the PID loop?

[Riton]

Its not hard to add 0 deadzone. But your motor minimum "step" should not overlap it as then it will keep trying to seek the position.

My minimum engine speed is 0 in the settings.
normally the PID does the job?

it must maintain position with just the minimum speed.
as the position is close he just needs to hold the load.

[Riton]

potentiometer support new development.
adjusting the tension of the belt

[Riton]

I hope I will soon replace the engines with more powerful engines.
My first test shows a lack of power.

inertia and high speed requires more power.

the first tests were done with 30 rpm motor 0.55 kw.

I will go to 1.1 kw motor 30 rpm, to a linear velocity of 480 mm / s

I have this time a reserve capacity!

I will soon weld the final elements, and the parts of the changes I made​​.

[tronicgr]

Hi Richard,

I don't tell people to "over-engineer" a little bit on the selection of motors for no reason. You see yourself its better to spend a few more bucks to have a good solution that will provide reserve power when needed (inertia, dislocation of load, extra equipment loaded on the platform cockpit later).

Thanks!
Thanos

[Riton]

yes, you right, I totally agree !!
I knew that the current engine would be just with power.
0.55kw is perfect for a 2-DOF with pivot.

for a 3 DOF suspended without spring 0.75 kw could perhaps be enough, but to play it safe I decided to choose a margin with 1.1kw.

because I want 30 rpm, and my cams 240 mm, giving 480 mm / s ! i need torque and speed.

the price difference is not significant.

the problem with the AC motor, when there is not enough power, they drop !!
DC motors force, slow speed,
we see less the lack of power
watch the video:
at 1.30 :with inertia :

[Riton]

first test with AMC128USB
480mms