Investigation of an engine order noise cancellation system in a super sports car

Today’s cars must meet ever-higher acoustic standards, and so, to avoid compromising vehicle dynamics, handling performance and fuel consumption, standard passive methods alone do not provide sufficient performance. Active control solutions can provide a potential solution to this challenge, particularly at low frequency and such systems have been investigated for application to small cars, SUVs and luxury vehicles. These vehicles are generally characterised by fairly slow dynamics and limited noise emission and, therefore, this paper explores the challenging application of active noise control to a two-seat super sports car equipped with a naturally aspirated engine. This work aims to track and then control sounds characterised by extremely rapid frequency variation rates, up to peaks of over 80 Hz/s, and high sound pressure levels. A multi-channel, multi-order FxLMS based control system has been implemented, which has been modified to optimise performance for this application by including both convergence gain and leakage scheduling, to achieve effective control at the driver’s and passenger’s ears. To evaluate the performance of the controller, its performance has been simulated when applied to measurements taken under several vehicle manoeuvres, ranging from conventional constant engine speed to very fast engine run-ups. From the presented results, it is shown that the system can obtain high levels of control during the manoeuvre set, with the controller reducing the overall sound pressure level by more than 10 dB at certain frequencies when analysing a single order, and it reduces the overall loudness by around 5% in all of the analysed cases

Investigation of an engine order noise cancellation system in a super sports car

Today’s cars must meet ever-higher acoustic standards, and so, to avoid compromising vehicle dynamics, handling performance and fuel consumption, standard passive methods alone do not provide sufficient performance. Active control solutions can provide a potential solution to this challenge, particularly at low frequency and such systems have been investigated for application to small cars, SUVs and luxury vehicles. These vehicles are generally characterised by fairly slow dynamics and limited noise emission and, therefore, this paper explores the challenging application of active noise control to a two-seat super sports car equipped with a naturally aspirated engine. This work aims to track and then control sounds characterised by extremely rapid frequency variation rates, up to peaks of over 80 Hz/s, and high sound pressure levels. A multi-channel, multi-order FxLMS based control system has been implemented, which has been modified to optimise performance for this application by including both convergence gain and leakage scheduling, to achieve effective control at the driver’s and passenger’s ears. To evaluate the performance of the controller, its performance has been simulated when applied to measurements taken under several vehicle manoeuvres, ranging from conventional constant engine speed to very fast engine run-ups. From the presented results, it is shown that the system can obtain high levels of control during the manoeuvre set, with the controller reducing the overall sound pressure level by more than 10 dB at certain frequencies when analysing a single order, and it reduces the overall loudness by around 5% in all of the analysed cases

Real-world candidacy to mavacamten in a contemporary hypertrophic obstructive cardiomyopathy population

Aims: In the EXPLORER-HCM trial, mavacamten reduced left ventricular outflow tract obstruction (LVOTO) and improved functional capacity of symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients. We sought to define the potential use of mavacamten by comparing real-world HOCM patients with those enrolled in EXPLORER-HCM and assessing their eligibility to treatment. Methods and results: We collected information on HOCM patients followed up at 25 Italian HCM outpatient clinics and with significant LVOTO (i.e. gradient ≥30 mmHg at rest or ≥50 mmHg after Valsalva manoeuvre or exercise) despite pharmacological or non-pharmacological therapy. Pharmacological or non-pharmacological therapy resolved LVOTO in 1044 (61.2%) of the 1706 HOCM patients under active follow-up, whereas 662 patients (38.8%) had persistent LVOTO. Compared to the EXPLORER-HCM trial population, these real-world HOCM patients were older (62.1 ± 14.3 vs. 58.5 ± 12.2 years, p = 0.02), had a lower body mass index (26.8 ± 5.3 vs. 29.7 ± 4.9 kg/m2 , p < 0.0001) and a more frequent history of atrial fibrillation (21.5% vs. 9.8%, p = 0.027). At echocardiography, they had lower left ventricular ejection fraction (LVEF, 66 ± 7% vs. 74 ± 6%, p < 0.0001), higher left ventricular outflow tract gradients at rest (60 ± 27 vs. 52 ± 29 mmHg, p = 0.003), and larger left atrial volume index (49 ± 16 vs. 40 ± 12 ml/m2 , p < 0.0001). Overall, 324 (48.9%) would have been eligible for enrolment in the EXPLORER-HCM trial and 339 (51.2%) for treatment with mavacamten according to European guidelines. Conclusions: Real-world HOCM patients differ from the EXPLORER-HCM population for their older age, lower LVEF and larger atrial volume, potentially reflecting a more advanced stage of the disease. About half of real-world HOCM patients were found eligible to mavacamten

Real-world candidacy to mavacamten in a contemporary hypertrophic obstructive cardiomyopathy population

Aims In the EXPLORER-HCM trial, mavacamten reduced left ventricular outflow tract obstruction (LVOTO) and improved functional capacity of symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients. We sought to define the potential use of mavacamten by comparing real-world HOCM patients with those enrolled in EXPLORER-HCM and assessing their eligibility to treatment.Methods and results We collected information on HOCM patients followed up at 25 Italian HCM outpatient clinics and with significant LVOTO (i.e. gradient >= 30 mmHg at rest or >= 50 mmHg after Valsalva manoeuvre or exercise) despite pharmacological or non-pharmacological therapy. Pharmacological or non-pharmacological therapy resolved LVOTO in 1044 (61.2%) of the 1706 HOCM patients under active follow-up, whereas 662 patients (38.8%) had persistent LVOTO. Compared to the EXPLORER-HCM trial population, these real-world HOCM patients were older (62.1 +/- 14.3 vs. 58.5 +/- 12.2 years, p = 0.02), had a lower body mass index (26.8 +/- 5.3 vs. 29.7 +/- 4.9 kg/m(2), p < 0.0001) and a more frequent history of atrial fibrillation (21.5% vs. 9.8%, p = 0.027). At echocardiography, they had lower left ventricular ejection fraction (LVEF, 66 +/- 7% vs. 74 +/- 6%, p < 0.0001), higher left ventricular outflow tract gradients at rest (60 +/- 27 vs. 52 +/- 29 mmHg, p = 0.003), and larger left atrial volume index (49 +/- 16 vs. 40 +/- 12 ml/m(2), p < 0.0001). Overall, 324 (48.9%) would have been eligible for enrolment in the EXPLORER-HCM trial and 339 (51.2%) for treatment with mavacamten according to European guidelines.Conclusions Real-world HOCM patients differ from the EXPLORER-HCM population for their older age, lower LVEF and larger atrial volume, potentially reflecting a more advanced stage of the disease. About half of real-world HOCM patients were found eligible to mavacamten