Car temperature / fuel / Tacho gauges

[lesthegrngo]

Hi All, for my race sim I used to use a set of cheapo Chinese made gauges connected via SimHub to output game data for an instrument binnacle that was a stand off replica of the Ferrari 312T4 dash. They worked very well, driven by a module controlled by an Arduino, which I believe used a PWM output to drive the gauges. Of course, when I went to VR it was shelved

For some of the DCS gauges I was wondering if I could use those types of instrument to show certain gauges, on the basis of it having smoother movement. So first question I have is what these gauges use for the mechanism - it is clearly not a stepper, and from my limited knowledge seems to be a coil and a sprung needle. What are these types of devices called, and are they available as bare mechanisms for me to have a play with to see what I could do? I could break open one of the gauges I already have but that would be an expensive way of doing it

I realise that they would have limited range of movement compared to the steppers, but maybe by gearing I can overcome that, and even then there are some gauges that don't require a great range. I know it wont replace steppers for all but maybe for smaller range more active devices it may be an option 

Les

[No1sonuk]

Sounds like a galvanometer or a moving coil meter.
You can buy them, but they're getting expensive because steppers or digital meters are replacing them.

[lesthegrngo]

Thanks- and yes, they are not cheap, so incredibly cannibalising the old Chinese car gauges may actually be cheaper!

I'll give it a go and see it it is worth it on one of them

Les 

[Vinc_Vega]

Hi Les,

Have a look at this guy's project!

https://hackaday.io/project/186478-arduino-weighing-machinescale-with-analog-showin

He uses an analogue 5V voltmeter, steered by Arduino PWM signals (remember: 0 to 5 Volts), to fake a weight scale.

Within his code the output simply reads

analogWrite (6,WEIGHT);

while 6 is the output pin and WEIGHT is the PWM value from 0 to 255.

https://cdn.hackaday.io/files/1864787978274752/CODE FINAL.txt

There seems to be no need for a library

So if your gauges are designed to work with 5V or less, it should be possible to move the pointers. It's than more or less a question of their calibration.

Regards, Vinc 

Edited September 2, 2024 by Vinc_Vega

[No1sonuk]

You have to make sure to use a PWM-capable output, though.