13 research outputs found

    Dynamika układu tylnego zawieszenia pojazdu z silnikami elektrycznymi wbudowanymi w koła

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    The dynamics analysis of the rear suspension system of the Fiat Panda III with electric motors mounted in wheels is presented in the paper. The simplified model of this system modeled using the multibody system dynamics method and the MSC. Adams package is proposed. In order to validate the proposed numerical model, the road tests were carried out consisting on passing the vehicle without motors in wheels at constant speed through the obstacle. The vertical displacement of the center of the vehicle wheel was measured during the tests. During the validation, parameters of the wheel-to-road contact, stiffness coefficients of springs and shock absorber damping coefficients of the suspension of the simulation model were modified so that the numerical results were consistent with the experiment. Further, such a tuned model was used to simulate the motion of suspension with the motors mounted into the wheels. The obtained results were validated, obtaining the accepted compatibility. In the following, a series of calculations was carried out in order to analyze the influence of stiffness coefficients of springs and shock absorber damping coefficients on the dynamic response of the suspension.W artykule przedstawiono analizę dynamiki układu tylnego zawieszenia samochodu Fiata Panda III z silnikami elektrycznymi wbudowanymi w koła. Uproszczony model układu uzyskano przez zastosowanie metod dynamiki układów wieloczłonowych i ich implementacji programowej w postaci pakietu MSC.Adams. W celu walidacji zaproponowanego modelu symulacyjnego wykonano testy drogowe polegające na przejeździe pojazdu bez silników wbudowanych w koła przez przeszkodę ze stałą prędkością. Podczas badań mierzono pionowe przemieszczenia środków kół pojazdu. W procesie walidacji modyfikowano parametry kontaktu koła z nawierzchnią, współczynniki sztywności sprężyn zawieszenia oraz współczynniki tłumienia amortyzatorów, tak aby otrzymać akceptowalną zgodność wyników numerycznych z eksperymentem. Dostrojony model symulacyjny został dalej użyty do symulacji ruchu zawieszenia z silnikami wbudowanymi w koła. Otrzymane wyniki dalej porównano z badaniami uzyskując akceptowalną zgodność. W pracy wykonano również szereg symulacji mających na celu zbadanie wpływu współczynników sztywności sprężyn zawieszenia i współczynników tłumienia amortyzatorów na odpowiedź dynamiczną układ tylnego zawieszenia

    Analysis of the Influence of Motors Installed in Passenger Car Wheels on the Torsion Beam of the Rear Axle Suspension

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    The influence of mounting motors in wheels’ hubs and flexibility of the twist beam rear suspension on their dynamics and strength is presented in the paper. The international roughness indicator (IRI) is applied to assess the overcoming of road unevenness. This indicator is a combination of a shape of the road unevenness and of overcoming velocity. The movement of a wheel’s axis during obstacles overcoming is described. For the needs of the dynamics analysis, the mathematical model of the rear suspension system with embedded motors is developed using the MSC.Adams-ANSYS interface. The discrete model of the twist beam is prepared in the ANSYS software, which is used in the next step to construct the dynamics model of the rear suspension system using the MSC.Adams program. The vertical components of displacement and acceleration of the wheel’s centre, forces in the suspension’s springs and dampers, as well as forces in the joints are analyzed. The analysis of the suspension beam’s stress during the road unevenness overcoming is also carried out

    Analysis of the Influence of Motors Installed in Passenger Car Wheels on the Torsion Beam of the Rear Axle Suspension

    No full text
    The influence of mounting motors in wheels’ hubs and flexibility of the twist beam rear suspension on their dynamics and strength is presented in the paper. The international roughness indicator (IRI) is applied to assess the overcoming of road unevenness. This indicator is a combination of a shape of the road unevenness and of overcoming velocity. The movement of a wheel’s axis during obstacles overcoming is described. For the needs of the dynamics analysis, the mathematical model of the rear suspension system with embedded motors is developed using the MSC.Adams-ANSYS interface. The discrete model of the twist beam is prepared in the ANSYS software, which is used in the next step to construct the dynamics model of the rear suspension system using the MSC.Adams program. The vertical components of displacement and acceleration of the wheel’s centre, forces in the suspension’s springs and dampers, as well as forces in the joints are analyzed. The analysis of the suspension beam’s stress during the road unevenness overcoming is also carried out

    Selected mechanical aspects of a car driven by electric wheel hub motors

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    The dynamics of the Fiat Panda III rear suspension system with electric motors built into the wheel hubs is presented in the paper. The results of the dynamics analysis presented in the article are a continuation of the authors' work on the impact of unsprung masses (here in the form of electric motors mounted in the wheel hubs) on the behavior of the rear suspension system and entire vehicle in various road conditions. The analyzes were carried out using multibody dynamics methods implemented in the MSC.Adams software. In previous works, the simulation model was validated by comparison numerical results with road tests, resulting in a verified numerical model with correctly selected physical parameters. This paper focuses on the analysis of the impact of the medium and high speed of passing over an obstacle ( υ ={30,60,120}km/h ) in the form of a rectangular bump and hole on the accelerations of wheel centers without motors and with electric motors embedded in the wheel hubs. Accelerations of the wheel centers are analyzed in the time and frequency domain.W artykule przedstawiono dynamikę układu tylnego zawieszenia samochodu Fiata Panda III z silnikami elektrycznymi wbudowanymi w koła. Przedstawione w niniejszym artykule wyniki analizy dynamiki są kontynuacją prac autorów nad wpływem mas nieresorowanych (w postaci silników elektrycznych wbudowanych w piastach kół), na zachowanie się układu tylnego zawieszenia, a rezultacie całego pojazdu w różnych warunkach drogowych. Analizy przeprowadzono stosując metody dynamiki układów wieloczłonowych (UW) zaimplementowane w oprogramowaniu MSC.Adams. We wcześniejszych pracach dokonano walidacji modelu symulacyjnego, poprzez porównanie wyników numerycznych z testami drogowymi, otrzymując w rezultacie zweryfikowany model numeryczny z poprawnie dobranymi parametrami fizycznymi. W niniejszej pracy skupiono się na analizie wpływu średnich i dużych prędkości przejazdu ( υ = {30,60,120 km/h} ) przez nierówność w postaci prostokątnej wypukłości oraz wgłębienia w jezdni o tych samych wymiarach na przyspieszenia środków kół bez silników oraz z silnikami elektrycznymi wbudowanymi w piastach kół. Przyspieszenia analizowano w dziedzinie czasu oraz w dziedzinie częstotliwości

    Analysis of the work of an electric wheel hub motor for selected driving parameters of car

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    Artykuł przedstawia konstrukcję silnika trakcyjnego do zabudowy w piaście koła samochodu osobowego. Autorzy przedstawili obliczone parametry pracy silnika dla dwóch następujących po sobie etapów przejazdu. Pierwszy dotyczył jazdy z prędkością równą 150 km/h. Drugi etap obejmował jazdę z prędkością 50 km/h po powierzchni o nachyleniu 20%. W artykule zostały przedstawione parametry pracy silnika dla każdego z etapów oraz wyniki analizy termicznej silnika w trakcie przejazdu.The article presents the construction of a electrical wheel hub traction motor for passenger car. Authors presented calculated parameters of operation for two consecutive ride stages. The first one concerned driving at a speed of . The second stage involved riding at on a slope. The article presents parameters of motor work for each stage and the results of thermal analysis of the motor during the ride

    Mitochondrial BK Channel Openers CGS7181 and CGS7184 Exhibit Cytotoxic Properties

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    Potassium channel openers (KCOs) have been shown to play a role in cytoprotection through the activation of mitochondrial potassium channels. Recently, in several reports, a number of data has been described as off-target actions for KCOs. In the present study, we investigated the effects of BKCa channel openers CGS7181, CGS7184, NS1619, and NS004 in neuronal cells. For the purpose of this research, we used a rat brain, the mouse hippocampal HT22 cells, and the human astrocytoma U-87 MG cell line. We showed that CGS7184 activated the mitochondrial BKCa (mitoBKCa) channel in single-channel recordings performed on astrocytoma mitoplasts. Moreover, when applied to the rat brain homogenate or isolated rat brain mitochondria, CGS7184 increased the oxygen consumption rate, and can thus be considered a potentially cytoprotective agent. However, experiments on intact neuronal HT22 cells revealed that both CGS7181 and CGS7184 induced HT22 cell death in a concentration- and time-dependent manner. By contrast, we did not observe cell death when NS1619 or NS004 was applied. CGS7184 toxicity was not abolished by BKCa channel inhibitors, suggesting that the observed effects were independent of a BKCa-type channel activity. CGS7184 treatment resulted in an increase of cytoplasmic Ca2+ concentration that likely involved efflux from internal calcium stores and the activation of calpains (calcium-dependent proteases). The cytotoxic effect of the channel opener was partially reversed by a calpain inhibitor. Our data show that KCOs under study not only activate mitoBKCa channels from brain tissue, but also induce cell death when used in cellular models

    Single-Channel Properties of the ROMK-Pore-Forming Subunit of the Mitochondrial ATP-Sensitive Potassium Channel

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    An increased flux of potassium ions into the mitochondrial matrix through the ATP-sensitive potassium channel (mitoKATP) has been shown to provide protection against ischemia-reperfusion injury. Recently, it was proposed that the mitochondrial-targeted isoform of the renal outer medullary potassium channel (ROMK) protein creates a pore-forming subunit of mitoKATP in heart mitochondria. Our research focuses on the properties of mitoKATP from heart-derived H9c2 cells. For the first time, we detected single-channel activity and describe the pharmacology of mitoKATP in the H9c2 heart-derived cells. The patch-clamping of mitoplasts from wild type (WT) and cells overexpressing ROMK2 revealed the existence of a potassium channel that exhibits the same basic properties previously attributed to mitoKATP. ROMK2 overexpression resulted in a significant increase of mitoKATP activity. The conductance of both channels in symmetric 150/150 mM KCl was around 97 ± 2 pS in WT cells and 94 ± 3 pS in cells overexpressing ROMK2. The channels were inhibited by 5-hydroxydecanoic acid (a mitoKATP inhibitor) and by Tertiapin Q (an inhibitor of both the ROMK-type channels and mitoKATP). Additionally, mitoKATP from cells overexpressing ROMK2 were inhibited by ATP/Mg2+ and activated by diazoxide. We used an assay based on proteinase K to examine the topology of the channel in the inner mitochondrial membrane and found that both termini of the protein localized to the mitochondrial matrix. We conclude that the observed activity of the channel formed by the ROMK protein corresponds to the electrophysiological and pharmacological properties of mitoKATP

    Carbon monoxide released by CORM-401 uncouples mitochondrial respiration and inhibits glycolysis in endothelial cells : a role for mitoBK_{Ca} channels

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    Abstract Carbon monoxide (CO), a product of heme degradation by heme oxygenases, plays an important role in vascular homeostasis. Recent evidence indicates that mitochondria are among a number of molecular targets that mediate the cellular actions of CO. In the present study we characterized the effects of CO released from CORM-401 on mitochondrial respiration and glycolysis in intact human endothelial cells using electron paramagnetic resonance (EPR) oximetry and the Seahorse XF technology. We found that CORM-401 (10-100 μM) induced a persistent increase in the oxygen consumption rate (OCR) that was accompanied by inhibition of glycolysis (extracellular acidification rate, ECAR) and a decrease in ATP-turnover. Furthermore, CORM-401 increased proton leak, diminished mitochondrial reserve capacity and enhanced non-mitochondrial respiration. Inactive CORM-401 (iCORM-401) neither induced mitochondrial uncoupling nor inhibited glycolysis, supporting a direct role of CO in the endothelial metabolic response induced by CORM-401. Interestingly, blockade of mitochondrial large-conductance calcium-regulated potassium ion channels (mitoBKCa) with paxilline abolished the increase in OCR promoted by CORM-401 without affecting ECAR; patch-clamp experiments confirmed that CO derived from CORM-401 activated mitoBKCa channels present in mitochondria. Conversely, stabilization of glycolysis by MG132 prevented CORM-401-mediated decrease in ECAR but did not modify the OCR response. In summary, we demonstrated in intact endothelial cells that CO induces a two-component metabolic response: uncoupling of mitochondrial respiration dependent on the activation of mitoBKCa channels and inhibition of glycolysis independent of mitoBKCa channels
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