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Greetings
I have replaced my two 'noisy' servo motors with a x40 stepper motor which has the concentric shaft for two needle gauges, and am running it with two Easydriver boards. (one for each needle)
I am using it for the PMDG B737 Duct Pressure gauge.
I have it all working but have noticed the needles in the sim, and hence the stepper needles move almost constantly with small changes as the duct pressure fluctuates during the flight.
Over time the needles loose their correct position as they have no way of confirming where they are in relation to what the sim is doing. The only way I can reset the stepper is to stop mobiflight and reset the zero position before running it again.
Is there a way to 'buffer' the stepper so it needs a bigger fsuipc offset change to activate a change in the stepper? Transform formula or other?
I already have a transform formula in place to convert the range : $*5.6875
Sim/Stepper: 3600 10240
Test value: 1365
Is there a way to 'buffer' the stepper so it needs a bigger fsuipc offset change to activate a change in the stepper? Transform formula or other?
I already have a transform formula in place to convert the range : $*5.6875
Sim/Stepper: 3600 10240
Test value: 1365
Hi
I have no valid data for these x40 Steppers with Easydriver. ( I normaly work with ULN2003 and BY40)
Whatever the Logic should be the same !
We have 2 Factors....
1. The real number of Steps, the motor need for a 360° Turn. I can not figure out if your 10240 is correct or if you adjust this, e.g. to reduce turning range of the gauge.
Important is.... A Motor can not make MORE single steps per 360° as this number.... Thats the "hard Limit" of the Motor itself!
2. The SIM Value. Here Mobiflight workes like in all other Configs with Full Numbers. So a Value of 1,01 and 1,99 is both shown as "1" . By a Multiply you can increase this .... e.g. $*100 occure in 1,01 = 101 1,99 = 199 ..... So we create 100 "more" Steps from Raw Value.
BUT This only work if the raw Value from sim is a Float Decimal.
Lets say the Sim gives only 1,2,3,4,5 .... Whatever we multiply it by 100 .... The highest now is 5*100=500 .... But we not have 500 more Steps.....
We only change the Output to 100,200,300,400,500 .
Means we can never gain more steps as the Raw Value support us by its count of different Situations !
Solution: Instead of other guys who need to increase there Raw Value ( to run the Motor smoother) YOU need inverted a Decrease of Numbers to avoid the small jumps.
Idea... i expect the raw Value give you 632 Values ( 3600/5.6875) Then simply divide the Number by 2 ( to half the raw steps)
Transform : ($*5.6875)/2 Sim Value 1800 ....
Or more extreme.... divide 4
Transform : ($*5.6875)/4 Sim Value 900 ....
Make a test.... How it looks like ! May its to hard without feeling smooth!
After a few months away from the sim I finally got a chance to try the solutions you suggested.
Dividing the raw data by 2 did not solve the problem, but after reading and re-reading your post, it got me thinking that you had actually provided the solution in your observations.
When you were confused with my 10240 stepper entry it got me thinking that it might be the cause of all the problems.
I went back to the drawing board and went through the setup process from step one. I found out that 10240 was indeed causing the issues. I changed the value to a much lower value (4000). This was found by a bit of research on the x40 stepper characteristics, what it was trying to replicate in the sim, and ALOT of trial and error.
I have now completed several long flights and both the needles hold the correct values for the duct pressures and do not 'creep' in any direction. Success!
I guess it is a lesson on sometimes if it don't look right, it probably isn't right.
My final config that works is: Sim/Stepper 1000 4000
Test Value: 1000, with interpolation settings 0 - 0
130 - 480 which works for me and the required sweep angle of the needle for the duct pressure gauge.
Many thanks for your insight and eventual solution to my problem.
Supporter
