to this subject i may be one of your allies, i not only work with and fit vehicle monitoring devices, but also have to repair and calibrate them for work, equally i see a good number of industrial plant units via instrumentation,
so if you want a much larger starting point look up "tachographs" a speed / rpm chart recorder, in NSW they are legally required for transit vehicles "TV-xxxx" plates, most buses and trucks manufactured in europe will generally come with one pre-installed, either as a separate unit mounted in the dash, or acting as the main speedometer / tachometer, they have a stylus for speed / tacho, but also a stylus that follows a triangle wave pattern for traversed distance, and a lower sytlus that scores a mark every 200m, that way if one of the styluses wher to be bent or inhibited the remaining data could be worked out from the other 2, they use wax coated charts, and the stylus etches a fine line revealing the black backing colour giving the impression of a fine black line,
next up would be the pen plotters, these are either flatbed or cicrular and were only in the past 2 decades popular in instrumentation before becoming obsolete, effectively a motor or clock-spring slowly wound the chart around at a fixed rate and recorded the input value in most cases taking a voltage signal of 1-5V or 4-20mA and making it represent a span on the chart,
these are still in use in some businesses for units that can still have either the wax charts are made for the model, or they have been able to refill the ink storage depending on how they are built,
and then onto the modern era, as tech became cheaper and some of the circa 1950/1960 units stopped having charts or ink or spare parts supplied, other companies began pushing for newer electronic units to be developed, and as they are to function as both a real time display and a recording device in most cases it resulted in some very interesting designs, though i will focus on one of the higher end circa early 1980's units i have had to play around with recently, firstly, it has both an internal storage element and a floppy disk drive built into the unit, allowing for long term logging like is expected with most of these systems, they store the data be it a chart a floppy or a file somewhere, so if there is an issue they can follow it back up,
the device has a 5 pin array that makes up its input selections, from memory supporting, voltages 0-200mV (pretty much all thermocouples with internal scaling factors) 1-5V (standard signal) resistance, e.g. a PT100, a resistance based temperature probe, 4-20mA and a few other odd ones, e.g. +-1V with 3 banks of those inputs, with one interesting feature in the current input, it uses a current mirror to maintain the smallest possible voltage drop on the external signal, which is rare to see even in fairly modern units, (generally use a 250 ohm resistor, 20mA x250 = 5V drop at full signal)
internally the newer unit supports scaling, custom ranging, and basic math to apply custom units to the percentage of the input, e.g. 44% = 213 beers per minute,
it also allows you to set dampening and integral responses on the input signal, allowing noise and spiking to be ignored, etc, something rare to see with the mechanical units, generally requiring a modification to the measuring element or for it to have the options available, (not common in the 1980's)
equally the device has a fixed sampling speed of about 1 second, however you can set the "chart feed rate" (remembering this was new at the time) for how often it actually stores a sample,
and as a quirky feature as it had to compete being new tech at the time, it also has a rather pronounced feature that calculates how much it has saved in ink and charts through using it,
the very new units get similar to digital storage oscilloscopes, for more math has been added, network, usb and memory card support added, even in some units some control elements added as they combine with controllers being most of the tech required is pretty much the same, though they generally get re-termed recording controller then,
ask any questions you may have, i might have more to chip in