Car model physics - Revision history

Duplode: Moving footnote to the end

2024-10-01T09:55:22Z

Moving footnote to the end

← Older revision		Revision as of 11:55, 1 October 2024
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	As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.		As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.

	{{Footn\|1}} Those experiments consist in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions gave a result of 1tl = 205ft, only marginally different from the real value of 1tl = (1024/5)ft.

	===Engine revolutions===		===Engine revolutions===
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	* [[Car files]], a general overview on file structure of a Stunts car.		* [[Car files]], a general overview on file structure of a Stunts car.
	* [[Car parameters]], a general-purprose tuning guide with concise descriptions of relevant CAR*.RES parameters.		* [[Car parameters]], a general-purprose tuning guide with concise descriptions of relevant CAR*.RES parameters.

			==Notes==

			{{Footn\|1}} Those experiments consist in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions gave a result of 1tl = 205ft, only marginally different from the real value of 1tl = (1024/5)ft.

	[[Category:Driving]]		[[Category:Driving]]
	[[Category:Modding]]		[[Category:Modding]]

Duplode: /* Model fundamentals and internal units */ Updating and correcting the length conversion

2024-10-01T09:54:28Z

Model fundamentals and internal units: Updating and correcting the length conversion

← Older revision		Revision as of 11:54, 1 October 2024
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	===Speed===		===Speed===

	Speed values are readily available, either through digital speedometer readings or evaluation screen top speed/impact speed data. ~~It is important to keep in mind, though,~~ that ~~these values are in miles per hour; and thus they are most likely not used directly by the game in~~ the ~~algorithms (as miles and hours are not convenient internal units). Furthermore, in-game~~ values are rounded down to the nearest integer, so in experiments ~~which require accurate knowledge of speed values the data may not be reliable~~. ~~Anyway~~, ~~mph speeds are relevant to the~~ game ~~mechanics~~ and ~~will be employed in~~ much ~~of the following discussions~~.		Speed values in miles per hour are readily available, either through digital speedometer readings or evaluation screen top speed/impact speed data. Note that the reported values are rounded down to the nearest integer, which puts a limit to the accuracy of various kinds of in-game experiments. Speed plays a crucial role in applying real units to Stunts physics, as it links time, which we know exactly in-game, and length, which is much harder to correlate with reality.

	===Length===		===Length===

	There are two main reference systems for defining length units in Stunts:		There are two main reference systems for defining length units in Stunts:
	* '''Track tiles''' are ~~useful as references~~ for ~~further exploration of game physics. Experiments for finding tile lengths consist simply in racing a car down a long straight at~~ a ~~constant and known speed and infer the travelled distance from the speed and the time elapsed~~. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions give a consistent result of '''1tl = 205ft''' (''tl'' ~~= tile length). Converting that result to meters gives~~ the ~~useful fact that one tile~~ length ~~is about 1/16th~~ of a ~~kilometre; since Stunts seems to use Imperial units mostly everywhere~~, ~~however~~, ~~we'll stick to the value in feet~~ for ~~now~~.
	* '''3D shape sizes''', which ~~can be accessed by [[stressed]],~~ for ~~instance~~. The graphic size unit in resources such as car1 and all objects at GAME*.3SH will be referred to as ''point'', or ''pt''. ~~It is easy to verify~~ a ~~track tile is made~~ of ~~1024pt; therefore, 1pt = (205/1024)ft, or, to a very good approximation,~~ '''1pt = 0.2ft''' . ~~These results may~~ be ~~useful to graphic designers; furthermore, points is a more reasonable possibility for unit used~~ in game ~~algorithms than most others (miles, tiles, feet, etc.). Another interesting fact is that trying to convert miles per hour to points per time step yield a surprisingly clean fraction:~~ '''1mph = (11/30)(pt/TS)'''		* '''Track tiles''', which provide are a natural unit for a driver. We will use ''tl'' as the symbol for the length of a tile, with the track area, for instance, being a 30tl x 30tl grid.

			* '''3D shape sizes''', which give us relative sizes for the objects in the game. The graphic size unit in resources such as car1 and all objects at GAME*.3SH will be referred to as ''point'', or ''pt''. Inspection with [[stressed]] readily shows that a '''1tl = 1024pt'''. The correlation between speed and length revealed by knowledge of the game internals implies that '''1pt = 0.2ft''', exactly. Furthermore, speed can be recast in internal game units using '''1mph = (11/30)(pt/TS)'''. These observations agree with the results of older, in-game experiments to find the conversion factor {{ToFoot\|1}}.

	As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.		As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.

			{{Footn\|1}} Those experiments consist in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions gave a result of 1tl = 205ft, only marginally different from the real value of 1tl = (1024/5)ft.

	===Engine revolutions===		===Engine revolutions===

Duplode: /* Engine revolutions */

2016-09-19T21:22:47Z

Engine revolutions

← Older revision		Revision as of 23:22, 19 September 2016
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	===Engine revolutions===		===Engine revolutions===

	It is quite evident from inspection ~~only~~ that the engine speed parameters in CAR.RES are given directly in rpm. Toying with maximum rpm parameters and the torque curve allows to prove beyond doubt that each byte in the torque curve corresponds to a 128rpm range. There is not much to add in this topic, except for mentioning that the conversion to SI units, 1rpm = (2pi/60)(rad/s), may occasionally be of some use.		It is quite evident from mere inspection that the engine speed parameters in CAR.RES are given directly in rpm. Toying with maximum rpm parameters and the torque curve allows to prove beyond doubt that each byte in the torque curve corresponds to a 128rpm range. There is not much to add in this topic, except for mentioning that the conversion to SI units, 1rpm = (2pi/60)(rad/s), may occasionally be of some use.

	===Gear ratios===		===Gear ratios===

Duplode: /* Length */

2016-09-19T21:22:05Z

Length

← Older revision		Revision as of 23:22, 19 September 2016
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	There are two main reference systems for defining length units in Stunts:		There are two main reference systems for defining length units in Stunts:
	* '''Track tiles''' are useful as references for further exploration of game physics. Experiments for finding tile lengths consist simply in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions give a consistent result of '''1tl = 205ft''' (''tl'' = tile length). Converting that result to meters gives the useful fact that one tile length is about 1/16th of a kilometre; since Stunts seems to use Imperial units mostly everywhere, however, we'll stick to the value in feet for now.		* '''Track tiles''' are useful as references for further exploration of game physics. Experiments for finding tile lengths consist simply in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions give a consistent result of '''1tl = 205ft''' (''tl'' = tile length). Converting that result to meters gives the useful fact that one tile length is about 1/16th of a kilometre; since Stunts seems to use Imperial units mostly everywhere, however, we'll stick to the value in feet for now.
	* '''3D shape sizes''', which can be accessed by [[stressed]], for instance. The graphic size unit in resources such as car1 and all objects at GAME*.3SH will be referred to as ''point'', or ''pt''. It is easy to verify a track tile is made of 1024pt; therefore, 1pt = (205/1024)ft, or, to a very good approximation, '''1pt=0.2ft''' . These results may be useful to graphic designers; furthermore, points is a more reasonable possibility for unit used in game algorithms than most others (miles, tiles, feet, etc.). Another interesting fact is that trying to convert miles per hour to points per time step yield a surprisingly clean fraction: '''1mph = (11/30)(pt/TS)'''		* '''3D shape sizes''', which can be accessed by [[stressed]], for instance. The graphic size unit in resources such as car1 and all objects at GAME*.3SH will be referred to as ''point'', or ''pt''. It is easy to verify a track tile is made of 1024pt; therefore, 1pt = (205/1024)ft, or, to a very good approximation, '''1pt = 0.2ft''' . These results may be useful to graphic designers; furthermore, points is a more reasonable possibility for unit used in game algorithms than most others (miles, tiles, feet, etc.). Another interesting fact is that trying to convert miles per hour to points per time step yield a surprisingly clean fraction: '''1mph = (11/30)(pt/TS)'''
	As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.		As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.

Duplode: /* Length */

2016-09-19T21:21:37Z

Length

← Older revision		Revision as of 23:21, 19 September 2016
Line 17:		Line 17:
	There are two main reference systems for defining length units in Stunts:		There are two main reference systems for defining length units in Stunts:
	* '''Track tiles''' are useful as references for further exploration of game physics. Experiments for finding tile lengths consist simply in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions give a consistent result of '''1tl = 205ft''' (''tl'' = tile length). Converting that result to meters gives the useful fact that one tile length is about 1/16th of a kilometre; since Stunts seems to use Imperial units mostly everywhere, however, we'll stick to the value in feet for now.		* '''Track tiles''' are useful as references for further exploration of game physics. Experiments for finding tile lengths consist simply in racing a car down a long straight at a constant and known speed and infer the travelled distance from the speed and the time elapsed. Performing these tests with high accuracy is not trivial, however, and usually requires CarBlaster trickery to lock the car into the desired speed. Repeating such runs under different conditions give a consistent result of '''1tl = 205ft''' (''tl'' = tile length). Converting that result to meters gives the useful fact that one tile length is about 1/16th of a kilometre; since Stunts seems to use Imperial units mostly everywhere, however, we'll stick to the value in feet for now.
	* '''3D shape sizes''', which can be accessed by [[stressed]], for instance. The graphic size unit in resources such as car1 and all objects at GAME*.3SH will be referred to as ''point'', or ''pt''. It is easy to verify a track tile is made of 1024pt; therefore, ~~'''~~1pt = (205/1024)ft~~'''~~, or, to a very good approximation, 0.2ft . These results may be useful to graphic designers; furthermore, points is a more reasonable possibility for unit used in game algorithms than most others (miles, tiles, feet, etc.). Another interesting fact is that trying to convert miles per hour to points per time step yield a surprisingly clean fraction: '''1mph = (11/30)(pt/TS)'''		* '''3D shape sizes''', which can be accessed by [[stressed]], for instance. The graphic size unit in resources such as car1 and all objects at GAME*.3SH will be referred to as ''point'', or ''pt''. It is easy to verify a track tile is made of 1024pt; therefore, 1pt = (205/1024)ft, or, to a very good approximation, '''1pt=0.2ft''' . These results may be useful to graphic designers; furthermore, points is a more reasonable possibility for unit used in game algorithms than most others (miles, tiles, feet, etc.). Another interesting fact is that trying to convert miles per hour to points per time step yield a surprisingly clean fraction: '''1mph = (11/30)(pt/TS)'''
	As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.		As a final note, it is useful to have in mind that 1mi = 5280ft = 2^553*11ft.

Duplode: /* Braking */

2012-06-05T02:39:40Z

Braking

← Older revision		Revision as of 04:39, 5 June 2012
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	Brakes in Stunts are a rather straightforward matter. Bytes 2Ah/2Bh define a linear scale of acceleration opposing to the car's movement that determines effectiveness of brakes. With 2Ah = 0 and 2Bh = 1 a car without aero drag will go from 169mph to a full stop in 8.45s. That corresponds to a deceleration of		Brakes in Stunts are a rather straightforward matter. Bytes 2Ah/2Bh define a linear scale of acceleration opposing to the car's movement that determines effectiveness of brakes. With 2Ah = 0 and 2Bh = 1 a car without aero drag will go from 169mph to a full stop in 8.45s. That corresponds to a deceleration of
	8.94m/(s^2), or 0.911g (1g = gravity acceleration at sea level); naturally, increments to 2Bh correspond to 1/256 of that amount. The use of acceleration instead of force here is not an oversight: ~~however naïve it may feel,~~ ''Stunts does not account for mass for braking!'' Aerodynamic drag will also slow down a car whenever the accelerator is not pushed (at least while the car is planted to the ground), that's why one gets the impression that brakes are more effective at higher speeds. Finally, a curious point is that if both brakes and aero drag are set to zero a car running on straight road will not slow down no matter what you do, due to the complete lack of opposing forces...		8.94m/(s^2), or 0.911g (1g = gravity acceleration at sea level); naturally, increments to 2Bh correspond to 1/256 of that amount. The use of acceleration instead of force here is not an oversight: ''Stunts does not account for mass for braking!'' Aerodynamic drag will also slow down a car whenever the accelerator is not pushed (at least while the car is planted to the ground), that's why one gets the impression that brakes are more effective at higher speeds. Finally, a curious point is that if both brakes and aero drag are set to zero a car running on straight road will not slow down no matter what you do, due to the complete lack of opposing forces...

	===Cornering grip===		===Cornering grip===

Duplode: /* Stunts vs. real cars */

2012-06-05T02:38:58Z

Stunts vs. real cars

← Older revision		Revision as of 04:38, 5 June 2012
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	\|}		\|}

	Some interesting analysis can be done on the figures presented above. First of all, we see that at least one car, the NSX, both mass and drag are accurate. In fact, even the torque peak (5300rpm on the real car) is correctly positioned! However, even on this very favourable case peak torque is some 13% below the expected value, the understimation getting quite large for other cars (reaching 32.5% for the GTO). However, not all is lost. For all cars but the ZR1, the understimation of torque seems to go hand in hand to a strong understimation of aerodynamical drag (most strikingly for Countach and GTO), as if the developers, while balancing higher gear acceleration versus top speed, tried to compensate one thing with the other... Corvette seems to fail the trend, as its aerodynamics are actually ~~worst~~ than it should. However, the ZR1 torque curve looks very strange even for Stunts standards, as if the low-rpm half got artificially raised for some kind of correction, so it wouldn't be very surprising if the scale was more wrong than usual anyway. But there's still the 13% discrepancy for the NSX... that can be justified, however. The simple model we discussed up to now does not include a number of smaller effects which drain power from the engine output, such as rolling resistance (tire friction against the ground) and energy losses at transmission system. The most consistent way of accounting for these in the limited framework of Stunts car model is scaling down the torque curve, and 13% wouldn't be too bad of an estimate for such a correction.		Some interesting analysis can be done on the figures presented above. First of all, we see that at least one car, the NSX, both mass and drag are accurate. In fact, even the torque peak (5300rpm on the real car) is correctly positioned! However, even on this very favourable case peak torque is some 13% below the expected value, the understimation getting quite large for other cars (reaching 32.5% for the GTO). However, not all is lost. For all cars but the ZR1, the understimation of torque seems to go hand in hand to a strong understimation of aerodynamical drag (most strikingly for Countach and GTO), as if the developers, while balancing higher gear acceleration versus top speed, tried to compensate one thing with the other... Corvette seems to fail the trend, as its aerodynamics are actually worse than it should. However, the ZR1 torque curve looks very strange even for Stunts standards, as if the low-rpm half got artificially raised for some kind of correction, so it wouldn't be very surprising if the scale was more wrong than usual anyway. But there's still the 13% discrepancy for the NSX... that can be justified, however. The simple model we discussed up to now does not include a number of smaller effects which drain power from the engine output, such as rolling resistance (tire friction against the ground) and energy losses at transmission system. The most consistent way of accounting for these in the limited framework of Stunts car model is scaling down the torque curve, and 13% wouldn't be too bad of an estimate for such a correction.

	'''The bottom line:''' The unit system adopted works pretty well, and it allows to rationalize for some shortcomings of the original car models of Stunts. If one wishes to convert real values to Stunts, however, scaling down torque curves for about 15%-20% will probably be necessary.		'''The bottom line:''' The unit system adopted works pretty well, and it allows to rationalize for some shortcomings of the original car models of Stunts. If one wishes to convert real values to Stunts, however, scaling down torque curves for about 15%-20% will probably be necessary.

Duplode: /* Stunts vs. real cars */

2012-06-05T02:38:16Z

Stunts vs. real cars

← Older revision		Revision as of 04:38, 5 June 2012
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	\|}		\|}

	Some interesting analysis can be done on the figures presented above. First of all, we see that at least one car, the NSX, both mass and drag are accurate. In fact, even the torque peak (5300rpm on the real car) is correctly positioned! However, even on this very favourable case peak torque is some 13% below the expected value, the understimation getting quite large for other cars (reaching 32.5% for the GTO). However, not all is lost. For all cars but the ZR1, the understimation of torque seems to go hand in hand to a strong understimation of aerodynamical drag (~~reaching near-comical proportions~~ for Countach and GTO), as if the developers, while balancing higher gear acceleration versus top speed, tried to compensate one thing with the other... Corvette seems to fail the trend, as its aerodynamics are actually worst than it should. However, the ZR1 torque curve looks very strange even for Stunts standards, as if the low-rpm half got artificially raised for some kind of correction, so it wouldn't be very surprising if the scale was more wrong than usual anyway. But there's still the 13% discrepancy for the NSX... that can be justified, however. The simple model we discussed up to now does not include a number of smaller effects which drain power from the engine output, such as rolling resistance (tire friction against the ground) and energy losses at transmission system. The most consistent way of accounting for these in the limited framework of Stunts car model is scaling down the torque curve, and 13% wouldn't be too bad of an estimate for such a correction.		Some interesting analysis can be done on the figures presented above. First of all, we see that at least one car, the NSX, both mass and drag are accurate. In fact, even the torque peak (5300rpm on the real car) is correctly positioned! However, even on this very favourable case peak torque is some 13% below the expected value, the understimation getting quite large for other cars (reaching 32.5% for the GTO). However, not all is lost. For all cars but the ZR1, the understimation of torque seems to go hand in hand to a strong understimation of aerodynamical drag (most strikingly for Countach and GTO), as if the developers, while balancing higher gear acceleration versus top speed, tried to compensate one thing with the other... Corvette seems to fail the trend, as its aerodynamics are actually worst than it should. However, the ZR1 torque curve looks very strange even for Stunts standards, as if the low-rpm half got artificially raised for some kind of correction, so it wouldn't be very surprising if the scale was more wrong than usual anyway. But there's still the 13% discrepancy for the NSX... that can be justified, however. The simple model we discussed up to now does not include a number of smaller effects which drain power from the engine output, such as rolling resistance (tire friction against the ground) and energy losses at transmission system. The most consistent way of accounting for these in the limited framework of Stunts car model is scaling down the torque curve, and 13% wouldn't be too bad of an estimate for such a correction.

	'''The bottom line:''' The unit system adopted works pretty well, and it allows to rationalize for some shortcomings of the original car models of Stunts. If one wishes to convert real values to Stunts, however, scaling down torque curves for about 15%-20% will probably be necessary.		'''The bottom line:''' The unit system adopted works pretty well, and it allows to rationalize for some shortcomings of the original car models of Stunts. If one wishes to convert real values to Stunts, however, scaling down torque curves for about 15%-20% will probably be necessary.

Duplode: /* Stunts vs. real cars */

2012-06-05T02:36:08Z

Stunts vs. real cars

← Older revision		Revision as of 04:36, 5 June 2012
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	So far, so good - we already have the keys to translate a number of CAR*.RES parameters in terms of real physics units. However, in order to do actual modeling from real-world data, we must be sure that the values we calculate indeed have the consistence we expect. The best way to do that is, arguably, contrasting the data on original cars modeled in Stunts with their real counterparts - even if the Stunts models are no standard for accuracy, they apppear to match the real cars reasonably well. As before, the main source of information here will be the CarTest 4.5 database.		So far, so good - we already have the keys to translate a number of CAR*.RES parameters in terms of real physics units. However, in order to do actual modeling from real-world data, we must be sure that the values we calculate indeed have the consistence we expect. The best way to do that is, arguably, contrasting the data on original cars modeled in Stunts with their real counterparts - even if the Stunts models are no standard for accuracy, they apppear to match the real cars reasonably well. As before, the main source of information here will be the CarTest 4.5 database.

	Detailed comparisons of gear ratios and torque curve shapes won't be presented here in order to avoid excessive cluttering of the discussion. It can be said, however, that gear ratios are surprisingly accurate for most cars, at least to the extent we can evaluate them - that is, quotients between different ratios for the same car, as opposed to absolute values, which ~~analysis~~ wouldn't make sense anyway since final drive ratios or tire radius are not in the model. The same can not be said of torque curve shapes, however. Probably the most striking example is LM002: the real car used Countach engines (see [http://en.wikipedia.org/wiki/Lamborghini_LM002 Wikipedia] on that subject), yet the torque curves for the LM002 and Countach are completely different. Also, maximum rpm, torque and power peak positions normally do not coincide with the real car data, the difference often being in the order of 1000rpm or more. Alongside with the rather wild discrepancies in mass seen for Audi, Lancia and LM002, that suggests quite a bit of improvisation by the guys at DSI during the modeling process... Anyway, some further insight on that matter can be gained by comparing masses, maximum torques and overalll drag coefficients for a few cars. Data will be presented in real units, with corresponding values in Stunts internal units (which as discussed before simply represent byte values for the appropriate parameters) enclosed in brackets. Drag constants were calculated from info available on CarTest as well, but since for some cars frontal section area was missing there is some degree of guessing in them (somewhat less than ~10% in worst cases, hopefully).		Detailed comparisons of gear ratios and torque curve shapes won't be presented here in order to avoid excessive cluttering of the discussion. It can be said, however, that gear ratios are surprisingly accurate for most cars, at least to the extent we can evaluate them - that is, quotients between different ratios for the same car, as opposed to absolute values, analysis of which wouldn't make sense anyway since final drive ratios or tire radius are not in the model. The same can not be said of torque curve shapes, however. Probably the most striking example is LM002: the real car used Countach engines (see [http://en.wikipedia.org/wiki/Lamborghini_LM002 Wikipedia] on that subject), yet the torque curves for the LM002 and Countach are completely different. Also, maximum rpm, torque and power peak positions normally do not coincide with the real car data, the difference often being in the order of 1000rpm or more. Alongside with the rather wild discrepancies in mass seen for Audi, Lancia and LM002, that suggests quite a bit of improvisation by the guys at DSI during the modeling process... Anyway, some further insight on that matter can be gained by comparing masses, maximum torques and overalll drag coefficients for a few cars. Data will be presented in real units, with corresponding values in Stunts internal units (which as discussed before simply represent byte values for the appropriate parameters) enclosed in brackets. Drag constants were calculated from info available on CarTest as well, but since for some cars frontal section area was missing there is some degree of guessing in them (somewhat less than ~10% in worst cases, hopefully).

	{\| style="padding:0.5em; margin:1em; width: 80%; text-align: center; background:#fafafa; border:1px solid grey"		{\| style="padding:0.5em; margin:1em; width: 80%; text-align: center; background:#fafafa; border:1px solid grey"
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	'''The bottom line:''' The unit system adopted works pretty well, and it allows to rationalize for some shortcomings of the original car models of Stunts. If one wishes to convert real values to Stunts, however, scaling down torque curves for about 15%-20% will probably be necessary.		'''The bottom line:''' The unit system adopted works pretty well, and it allows to rationalize for some shortcomings of the original car models of Stunts. If one wishes to convert real values to Stunts, however, scaling down torque curves for about 15%-20% will probably be necessary.


	==Additional parameters and effects==		==Additional parameters and effects==

Duplode: /* Torque and mass */

2012-06-05T02:31:41Z

Torque and mass

← Older revision		Revision as of 04:31, 5 June 2012
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	The race cars (Indy and IMSA) were excluded due to the lack of reliable data, while [[Audi Quattro Sport\|Audi]], [[Lancia Delta Integrale\|Lancia]] and [[Lamborghini LM-002\|LM002]] aren't here for they in-game mass is strongly underestimated (far above the average error margin on the table above) in comparison to the other cars. Anyway, from the table it is apparent the 28h values are reasonably consistent, and that an unit byte increase equals roughly 100lb. Now, if we take 1msu = 100lb and substitute back into the previous result we get, after some unit manipulations, 1tsu ~= 3,87 lbfft (lbfft, usually quoted as just "lb-ft", is the most common Imperial unit for measuring a car's torque). Considering the mass values on the table are always somewhat higher than 100lbbyte_28h and the correspondence between mass values is not extremely accurate anyway, it seems reasonable to round the tsu value to 4lbfft for added convenience. That leaves us with the useful relations we had be looking for:		The race cars (Indy and IMSA) were excluded due to the lack of reliable data, while [[Audi Quattro Sport\|Audi]], [[Lancia Delta Integrale\|Lancia]] and [[Lamborghini LM-002\|LM002]] aren't here for they in-game mass is strongly underestimated (far above the average error margin on the table above) in comparison to the other cars. Anyway, from the table it is apparent the 28h values are reasonably consistent, and that an unit byte increase equals roughly 100lb. Now, if we take 1msu = 100lb and substitute back into the previous result we get, after some unit manipulations, 1tsu ~= 3,87 lbfft (lbfft, usually quoted as just "lb-ft", is the most common Imperial unit for measuring a car's torque). Considering the mass values on the table are always somewhat higher than 100lbbyte_28h and the correspondence between mass values is not extremely accurate anyway, it seems reasonable to round the tsu value to 4lbfft for added convenience. That leaves us with the useful relations we had been looking for:

	'''1tsu = 4lbf*ft'''		'''1tsu = 4lbf*ft'''