Muddy & Chippy on the road

Heute habe ich wieder das „Low-Budget-PnP-Tweeter-Upgrade“ vorgenommen, welches ich genauso schon in Chō eingebaut hatte…😎

Tweeter aus der Hertz-Cento-Serie… https://hertz-audio.com/product/c-26-oe/

IMG_0186.jpgIMG_1079.jpeg

Mit dem Dremel etwas nachgearbeitet

IMG_5047.jpgIMG_1075.jpg

Diesmal mit Wago-Klemmen, da ich gerade nix anderes zur Hand hatte…

IMG_1077.jpg

Klingt… passt👍🏻 Türen und Holme werden bei anderer Gelegenheit noch etwas gedämmt und die Löcher in der TMT-Verkleidung nachgebohrt. Mehr brauch ich nicht für einen passablen Klangteppich…

Zitat von Miatadriver

Erzähl mal mehr dazu.

Hast du das Bose-System verbaut?

Wie würdest du die Veränderung beschreiben?

Ich habe kein Bose-System verbaut. Das unterscheidet sich eklatant von dem Non-Bose. Insbesondere haben die einzelnen Lautsprecher-Chassis teilweise sehr verschiedene Impedanzen. Daher muss man die unterschiedlichen Umbaumaßnahmen sehr genau trennen…

Beim Non-Bose kann man mit verhältnismäßig wenig Aufwand einen ganz passablen Stereo-Klang hinbekommen. Mein Ansatz ist der Einfachste, da ich da nur die Hochtöner ersetze. Der originale TMT ist gar nicht so schlecht. In Verbindung mit Türdämmung und dem Aufbohren der vielen „Zierlöcher“ in der Türblende kommt da schon relativ knackiger Klang raus. Der serienmäßige HT ist IMHO der Flaschenhals, der den Klang sehr flach und unnatürlich klingen lässt. Habe diesen dann durch einen größeren und „angenehmeren“ ausgetauscht. Mit der beiliegenden 6db-Weiche und etwas Anpassung über die Klangoptionen im MZD und Spotify-Equalizer passt das für mich klangtechnisch…

Beim Bose kann man HT und TMT tauschen gegen Systeme mit passenden Impedanzen. Das klingt dann wohl auch besser. Richtig gut wird ein Bose nie klingen, aber das ist so eine grundsätzliche Geschichte. Die einen mögen es, die anderen kriegen Ohrenkrämpfe wegen dem grottigen Frequenzverlauf… ich zähle mich zu den letzteren und würde daher nie (mehr) eine Ausstattungslinie mit Bose-System kaufen.

Vom MAS noch 2 „Essentials“ mitgebracht und eingebaut… Stubby und schwarze LED-Blinker

IMG_1086.jpg

Zitat von Miatadriver

Das mit dem Bose sehe ich mittlerweile ähnlich, da ein Umbau sehr schwierig und nahezu immer mit Einschränkungen verbunden ist.

Ich hatte hier auch den Umbauthread gelesen, ein sauberes Ergebnis ist bei Non-Bose kein Problem, ich hab nun mal leider Bose drin.

Ich hatte auch mit einem Treiben HT-Umbau geliebäugelt, aber noch keinen passenden HT gefunden.

Daher meine Frage, obwohl mir die Impedanz schon zu hoch vorkam für Bose.

Ich glaube, beim Bose sind das 3Ohm Impedanz… und hier im Forum gibt es einen Thread zum Bose und Umbauvarianten, vielleicht findest Du da ja Anregung

Ich werde weiter unten meine subjektiven Erfahrungen zum KPC mitteilen… ganz bewußt an dieser Stelle, da es nur um meinen MX-5 gehen soll und ich keine neue Diskussionen zum KPC anstoßen will. Unter anderem aus dem Grund, dass man das so nicht verallgemeinern kann bei den verschiedenen Modellvarianten und Umbauten. Um das Ganze aber für den interessierten Leser etwas interessanter zu gestalten, hier die mühevolle Übersetzung des Papers der Entwickler in der letzten Technical Review als Grundlage…

Technical Review 2022 Kinematic Posture Control KPC

Übersetzung des pdf-Papers via Google Translate JAP-ENG: https://www.mazda.com/globalas…2022/files/2022_no031.pdf

1.First of all

As shown in Fig. 1, the authors developed and applied G-Vectoring Control Plus (hereinafter referred to as GVC Plus), which enabled the sprung body posture from corner turn-in to turn-out to be controlled by the driver's operation and feel. have been shown to affect the ring (1-3).

IMG_0407.png

A common feature of the rear suspension geometry of rear-wheel drive (RWD) mass-produced vehicles such as the Roadster is that the rear roll center height is relatively higher than the front. As a result, the lifting force due to the jack-up effect of the front and rear outer wheels due to the tire lateral force becomes superior to the front. As a result of using this geometry effect, the front-down pitch at turn-in shown in Fig. 1 can be naturally realized. However, in a configuration with a high rear roll center, excessive jack-up force is produced in scenes with large lateral acceleration, causing heave motion in which the vehicle body lifts when turning, making the driver feel uneasy. There is Therefore, this time, we investigated a method to suppress the heave that increases in scenes where the turning lateral acceleration of the RWD vehicle is large. As a result, the anti-lift geometry of the rear suspension shown in Fig. 2 was improved.

Kinematic Posture Control (KPC) is a new vehicle motion control that stabilizes the posture of the sprung body by suppressing heave by using the force to pull down the sprung body and the anti-lift force generated by the combination of the steering wheel and the rear wheel braking inside the turn. developed. In this paper, we report an overview of the control and system configuration, as well as the results of an objective and quantitative evaluation of the effects of KPC.

IMG_0408.jpg

2. KPC concept

KPC is a vehicle motion control that realizes heave suppression by combining suspension geometry and braking force. Figure 3 shows an overview of the control logic. As the yaw rate r occurs during cornering, when Vdiff, which is the difference between the left and right rear wheel speeds VO,I, exceeds the control intervention threshold Vthreshhold, braking force FRin is applied to the inner rear wheels to suppress heave. The required anti-lift force FAL is applied to the bodywork. The control that applies braking force to the inner rear wheels of a turn using KPC is similar to Direct Yaw-Moment Control (14) (hereafter referred to as DYC: control that promotes yaw motion using the difference in braking and driving forces between the inner and outer wheels of a turn). However, the braking force FRin is limited to a small value that hardly promotes yaw motion. KPC is a control based on the concept of controlling only the heave without changing the plane motion of the vehicle.

IMG_0410.png

When it is implemented in a vehicle, the braking force FRin of the turning inner wheel is used as the control command value when the left and right wheel speed difference Vdiff exceeds the threshold as shown in Eq. (1). The magnitude of this braking force is determined according to the speed difference between the left and right wheels.

Taking a more specific driving scene as an example, at a corner with a large turning radius shown in Fig. 4(i), the difference in wheel speed between the left and right wheels is small, and the lateral acceleration generated in the vehicle is also small, so the heave of the vehicle is also small. . On the other hand, at a corner with a small turning radius shown in Fig. 4(ii), the vehicle heave increases due to the large wheel speed difference between the left and right wheels and the large lateral acceleration. Therefore, control that takes into account the difference in wheel speed between the left and right wheels automatically adjusts the amount of control according to the turning radius. In addition, by using the left and right wheel speed difference, even if the driver operates the steering wheel in the direction opposite to the turning direction, such as countersteering, it is possible to execute control in the appropriate direction for the turning direction of the vehicle.

IMG_0411.jpg

In addition, the difference in wheel speed between the left and right wheels depends not only on the driving scene, but also on differences in vehicle specifications. For example, a car with an open differential shown in Fig. 5(i) is equipped with a Limited Slip Differential (LSD), which is a limited slip differential shown in Fig. 5(ii). In addition to limiting the difference in wheel speed between the left and right wheels, yaw motion is suppressed by the difference in driving force between the left and right wheels, resulting in high stability and reduced anxiety about heave. KPC works weakly in LSD-equipped vehicles where the wheel speed difference is small. By referring to the wheel speed difference, not only the driving scene but also the characteristics of the vehicle to be installed are naturally taken into consideration, making it possible to calculate an appropriate control amount.

IMG_0422.png

Vehicle with KPC and implementation

3.1 Vehicle specifications and suspension geometry

KPC is a control method that can be applied to various vehicles depending on the rear suspension geometry. In this paper, as an example, the Roadster, which is one of the vehicles in Table 1, (Fig.6) shows the results of verification with KPC installed.

IMG_0413.pngIMG_0414.png

3.2 Implementation of KPC

Fig.7 shows the system configuration diagram of KPC. Vehicle status through the vehicle's Controller Area Network (CAN) number

detected and expressed in the formula in the Powertrain Control Module (PCM).

Calculations based on the KPC concept in (1) are performed, and Brake

Outputs control commands to the Control Unit (BCU). Electronic sideslip prevention device that must be installed on commercial vehicles

Stability Control (ESC) is used, and no additional equipment is required to install KPC.

IMG_0415.jpg

… weiter im nächsten Post

4. Verification by full vehicle simulation

4.1 Verification by full vehicle simulation

(1) Vehicle motion model

In order to verify the effectiveness of the KPC concept described in Chapter 2, a full vehicle simulation was performed using the vehicle motion model of previous research”). It is a dynamic model that reproduces the suspension mechanism, and can analyze the roll, pitch, and heave of the sprung body caused by the longitudinal and lateral forces of the tires being transmitted to the body through the suspension.

The vehicle specifications used in the simulation are the same as those in Table 1.

(2) Simulation results

As shown in Fig. 8, the simulation conditions were to enter at a vehicle speed of 54 [km/h], cut the steering angle to 80 [deg], and then turn back. With KPC, the peak value is approx.

of the braking force was applied to the inside rear wheel of the turn.

In order to confirm the transitional changes in the planar motion of the vehicle and the sprung body posture during steering, the vehicle motion parameter changes in the turning-on state relative to the turning-side steering angle of 60 degrees. are shown in Table 2.

IMG_0416.jpgIMG_0417.jpg

The yaw rate increases by 0.08% when the steering angle is 60 degrees, and there is almost no change with KPC ON/OFF. In addition, the roll angle and pitch angle decreased by 0.34% and increased by 0.55%, respectively, and remained almost unchanged with KPC ON/OFF. On the other hand, heave decreased by 3.16%, which is larger than other changes. Looking at the relationship between the yaw rate and heave for steering on the turning side using the Lissajous waveform, there is almost no difference in yaw rate between KPC ON and OFF, but the heave is smaller with KPC ON (Fig.9). In this way, it was confirmed that only the heave can be suppressed without changing the yaw, roll, and pitch movements by generating a braking force on the inside rear wheel within a range in which the yaw rate response to the steering operation during a turn is small.

IMG_0418.jpg

Table 3 shows the results of an investigation of the yaw, roll, pitch, and heave motion when a braking force similar to that of the KPC was applied to the wheels other than the inner rear wheels to which the braking force was applied by the KPC.

shown in In the case of the front wheels inside and outside the turn, the pitch angle increased by about 3 to 4%, and there was almost no change in heave. but out of turn

For the rear wheels, the heap was reduced by 4.70% and the

Larger than the rear wheels (approximately 1.1 times), and the yaw rate is also reduced by 0.37% (approximately 4.6 times), so while it is possible to suppress heave in the same way as the inner rear wheels, the force that damps yaw motion is also possible. is known to occur easily.

IMG_0419.jpg

From the above results, when the braking wheel is the inside rear wheel, a certain braking force is applied.

It was confirmed that only the heave can be suppressed without changing the yaw, roll and pitch motion within the power range. As shown in Table 1, the vehicle equipped with KPC this time has a large rear anti-lift angle of 22.2 [deg], so a small amount of braking force generates a large anti-lift force. Therefore, heave of the vehicle body can be suppressed without changing the yaw motion.

4.2 Verification by actual running measurement

(1) Driving mode

As in the desktop simulation in section 4.1, the approach vehicle speed is 54

[km/h], maximum steering angle of about 80 [deg], KPC effect was verified in actual driving in a U-turn. The vehicle speed is adjusted while driving straight before entering the vehicle, and after that, the accelerator opening is kept constant with a dedicated device for measurement, and the driver only operates the steering wheel to turn. After obtaining informed consent, the subjects were instructed to run as much as possible in the same manner as the experiment. Fig. 10 shows the measured running trajectory. KPCON

is indicated by a red line, and KPC OFF is indicated by a black line.

IMG_0421.png

(2) Measurement results

The measurement results are shown in Fig. 11. The heave was obtained from the measured values of height gauges attached to the four corners of the vehicle, and the KPC flag in the PCM was measured in synchronization with other measured values.

As in Fig. 10, KPC ON is indicated by a red line, and KPCOFF is indicated by a black line.

is working. Comparing the heave during KPC operation, the heave is small with KPC ON. After suppressing heave, the operation after 7 seconds is different depending on KPC ON/OFF.

In the case of KPC ON, the return is smooth, but in the case of KPC OFF, the initial return is sharp. As for the yaw rate, the steering angle changes after 7 seconds, but there is almost no difference before the KPC is activated. The left figure of Fig.12 shows the relationship between steering angle and yaw rate.

It can be seen that there is no difference in On the other hand, the heap on the right shows a clear difference between KPCON/OFF, and it can be seen that KPC reduced the heap by about 1 [mm].

As described above, as a result of comparing U-turn turning with KPC ON/OFF, it was confirmed that the yaw rate does not change much with KPC and the heave becomes smaller with KPC, similar to the full vehicle simulation results in section 4.1. In addition, the reduction in heap changes the driver's steering behavior, and the KPC operation also has the effect of smoothing the return steering. We were able to confirm that by suppressing heave during cornering, the driver is able to operate the steering wheel with a sense of leeway without having to steer sharply, including at high frequencies.

IMG_0423.pngIMG_0424.png

4.3 Verification on general road driving

As in Section 4.2, ground height gauges were attached to the four corners of the vehicle.

We ran on a winding road in the suburbs of Europe.

Sprung vehicle during cornering (lateral acceleration = 0.45 [C])

Fig. 13 shows a contour diagram showing the body posture, and Fig. 14 shows the vertical movement of the vehicle center point at that time. It can be seen that the turning posture of the car body is reversed from the floating direction to the sinking direction by KPC. It was confirmed that the heap control effect as intended was achieved even on ordinary roads.

IMG_0425.pngIMG_0426.png

In addition, vehicle speed that reproduces the severe road environment of European general roads,

High lateral turning acceleration and many road undulations

KPC ON/OFF the time-series waveform when driving the Nirburgring

Fig. 15 shows the results of the comparison in . In part A of the figure, when the black line shows the KPC OFF, the driver feels uneasy when the vehicle lifts and pulls off the accelerator pedal. I confirmed that I was able to accelerate toward exiting the corner without correcting the accelerator pedal.

IMG_0427.png

Based on these results, sensory evaluations were conducted by comparing the presence or absence of KPC on a large number of drivers in Japan and overseas, including general drivers. The comments obtained are described below. As the vehicle dynamics concept shown in Fig. 1 was aimed at, it can be confirmed that by suppressing heave during turns, the driver has more leeway to operate the vehicle and is able to operate the vehicle with self-reliance.

KPC evaluation comments)

* From corner turn-in to exit, the roll in the floating direction is suppressed, and you can feel the effect of improving the grounding feeling.

* The feeling of ground contact on the inner wheel side is improved in corners with undulations.

* Good controllability in S-shaped corners.

* Because the rear is stable when exiting the corner, you can step on the accelerator.

5. Conclusion

We have developed a KPC that controls the vehicle body posture according to the difference in left and right wheel speeds at the rear during cornering. DYC gives a yaw moment due to the difference in braking/driving force between the left and right wheels, but KPC produces a significantly smaller braking force due to braking. Therefore, the yaw moment generated in the vehicle is small and the yaw motion hardly changes. On the other hand, for the heap, the amplification effect combined with the suspension geometry

It was confirmed by simulation results and actual vehicle measurements that it was reduced. By suppressing heap, KPC stabilizes the vehicle posture that the driver feels and has the effect of smoothing the steering. As described in previous research (), longitudinal acceleration and

In addition to the pitch, it was confirmed that the heave also affected the driver's operation.