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Among several typical energy storage methods, that flywheel energy storage has advantages such as high instantaneous power, high-performance and long service life, making it perfect secondary energy storage technology for traditional internal combustion engine vehicles. Although some progress has been made in the applied research of flywheel energy storage technology, there are no detailed studies at home and abroad that summarize its application in the vehicle applications. This paper searches the data on «flywheel energy storage», analyzes the research progress of flywheel energy storage in automotive industry, and analyzes the research progress of flywheel energy storage in vehicle applications. The search data show that flywheel energy storage technology for the vehicle applications has been studied for the last 20 years, although it is a niche research area. With respect to two typical flywheel hybrid systems, namely electric and mechanical drive, we have focused on the history of the study, research and validation of mechanical flywheel hybrid system in the automotive industry, as well as the structural characteristics of this system, the current state of research and future research trends.

Introduction: With the development of technology, the hydraulic control system for hydro-mechanical continuously variable transmission has also made rapid progress. However, the traditional control system for hydro-mechanical continuously variable transmission has drawbacks such as efficiency loss and slow response speed. The study fused the adaptive and pulse width modulation algorithms to solve these problems effectively, and they were applied to the hydraulic mechanical continuously variable drive control system. Method: First, the study analyzed the continuously variable transmission control of hydraulic machinery and designed the control scheme on the basis of the analysis. Then, a new scheme fusing adaptive and pulse-width modulation algorithms was proposed on the basis of the control scheme. Finally, simulation experiments and practical tests were carried out to verify the performance of the control scheme. Results: The results showed that the time to reach the maximum pressure was 2.15 s when the volume of the pilot valve cavity was 5 × 109/L. When the oil flow rate was 70 L/min, the corresponding maximum and minimum values of the main oil circuit pressure were 1.63 MPa and 0.37 MPa, respectively. The time to reach the maximum value of the pressure was 2.05 s, respectively. These values were in line with the design requirements and were better than the comparison values. Discussion: These results confirm that the system has important theoretical and practical significance, which has a positive promoting effect on the development of the hydraulic machinery industry. This article aims to provide a new approach for research and application in related fields. [ABSTRACT FROM AUTHOR]

Twisted string actuators, which are an emerging artificial muscle, efficiently convert rotary motor motion into linear load movement, with advantages like high transmission ratio, compliance, simple structure, and long-distance power transmission. However, the limited range of transmission ratio adjustment remains a challenge. Thus, this paper introduces a novel twisted string actuator design that automatically and continuously adjusts its transmission ratio in response to external loads. Utilizing lightweight hyperelastic slender rods, the twisted string actuator with continuously variable transmission achieves a simple, compact, and cost-effective design. By manipulating the distance between two twisted strings through rod deformation, the transmission ratio continuously adapts to varying load conditions. Mathematical models of the twisted string actuator with continuously variable transmission are derived and experimentally validated, demonstrating a 2.1-fold transmission ratio variation from 0.1 kg to 1.5 kg loads. Application in an anthropomorphic robot finger showcases a 6.2-fold transmission ratio change between unloaded and loaded states. Our twisted string actuator with continuously variable transmission offers unparalleled advantages in weight, cost, simplicity, compliance, and continuous transmission ratio adjustability, making it highly suitable for robotic systems. [ABSTRACT FROM AUTHOR]

With the rapid development and technological progress of the automobile industry, the performance testing and evaluation of the automobile powertrain system has become more and more important. This study designs an automotive powertrain test platform based on a photoelectric torque sensor. The study utilizes Kalman filtering to improve the photoelectric torque sensor and then establishes a power model based on the components of the automotive powertrain, such as the generator. Experimental verification is carried out using metal-belt continuously variable transmission. The loss rate of the proposed transmission system is 31% when compared to those of other transmission systems as 46% and 49% respectively. Compared with other driveline systems, the proposed power train system gave the least loss rate and smoother response data meaning the measured torque is more accurate. The proposed system also extends the service life compared with other systems due to better torque control. [ABSTRACT FROM AUTHOR]

In China's Yangtze River and Yellow River basin cotton-growing regions, the complex terrain, scattered planting areas, and poor adaptability of the existing machinery have led to a mechanized cotton harvesting rate of less than 10%. To address this issue, we designed a crawler chassis for a brush-roller cotton harvester. It is specifically tailored to meet the 76 cm row spacing agronomic requirement. We also conducted a theoretical analysis of the power transmission system for the crawler chassis. Initially, we considered the terrain characteristics of China's inland cotton-growing regions and the current cotton agronomy practices. Based on these, we selected and designed the power system and chassis; then, a finite element static analysis was carried out on the chassis frame to ensure safety during operation; finally, field tests on the harvester's operability, stability, and speed were carried out. The results show that the inverted trapezoidal crawler walking device, combined with a hydraulic continuously variable transmission and rear-drive design, enhances the crawler's passability. The crawler parameters included a ground contact length of 1650 mm, a maximum ground clearance of 270 mm, a maximum operating speed of 6.1 km/h, and an actual turning radius of 2300 mm. The maximum deformation of the frame was 2.198 mm, the deformation of the walking chassis was 1.0716 mm, the maximum equivalent stress was 216.96 MPa, and the average equivalent stress of the entire frame was 5.6356 MPa, which complies with the physical properties of the selected material, Q235. The designed cotton harvester crawler chassis features stable straight-line and steering performance. The vehicle's speed can be adjusted based on the complexity of the terrain, with timely steering responses, minimal compaction on cotton, and reduced soil damage, meeting the requirements for mechanized harvesting in China's inland small plots. [ABSTRACT FROM AUTHOR]

The wheel motor drive has the problem of insufficient power at low speeds when climbing hills. In this study, a new planetary roller wheel continuously variable transmission (CVT) is developed, which achieves independent variable speed drive of the wheel hub by means of multiple sets of roller friction drives. The inner ring of the wheel is an internal gear ring, driven by multiple planetary distribution gears to increase the wheel drive power. The actual working radius of the centre and distribution wheels is changed by controlling the angle of oscillation of the friction rollers to achieve continuity and stability of the speed change process. Motion simulation experiments using Adams software conclude that the CVT has a smooth and continuous speed, high transmission efficiency and smooth motion.

In order to improve the speed stability of tractors equipped with hydro-mechanical continuously variable transmission (HMCVT) during field operations, the speed regulation characteristics, torque characteristics, and power diversion characteristics of HMCVT are analyzed. And a comprehensive control strategy for HMCVT output speed is proposed by analyzing the factors affecting the fluctuation of output speed, which combines engine speed control and displacement ratio control of hydraulic speed control system. This strategy adopts fuzzy control to regulate the engine speed to maintain the stability of engine operation. Moreover, adopting feed forward compensation control for speed compensation enhances the anti-interference ability of the hydraulic speed control system. And combined with model predictive control, adjust the swash plate swing angle of the variable pump to reduce the fluctuation of HMCVT output speed. By establishing joint simulation model, the effectiveness of the control strategy was verified using tractor acceleration mode and step load disturbance mode. The results show that the strategy can reduce the fluctuation rate of engine speed and impact degree, shorten the adjustment time, and improve the stability of tractor operating speed. [ABSTRACT FROM AUTHOR]

The multi-degree-of-freedom characteristics of the planetary gear electronic continuously variable transmission (ECVT) configuration in series-parallel hybrid tractors impose more complex requirements for energy management strategies under variable load conditions. For a high-power hybrid tractor, this paper takes the hybrid tractor output-split (OS)-ECVT configuration as the research object and describes the principles of stepless transmission and power-splitting within the configuration. In order to improve the fuel economy of high-power hybrid tractors and the running status of power components, an energy management strategy focused on ploughing conditions based on the Bellman minimum dynamic programming (DP) algorithm is proposed in this paper. Second, equivalent fuel consumption is selected as the performance index for energy-saving control, and the solving principle of the energy management strategy based on the dynamic programming algorithm is established to facilitate the resolution process of the energy management strategy. Finally, the energy-saving control simulation is completed under ploughing conditions. The results show that compared with the energy management strategy based on the optimal operating line (OOL), the energy management strategy based on DP fully utilizes the benefits of low-cost electric energy and enables the hybrid power system to have a wider range of stepless transmission performance. In addition, the hybrid power system has the advantages of enhanced decoupling of speed and torque, higher efficiency, and more economical secondary energy conversion. As a result, the whole machine has enhanced power-split performance, greatly improving the running conditions of the power components. The equivalent fuel consumption values of the energy management strategies based on DP and OOL are about 3.1238 L and 4.2713 L, respectively. The equivalent fuel consumption based on DP is reduced by about 26.87%, which effectively improves the fuel efficiency of hybrid tractors. [ABSTRACT FROM AUTHOR]

In recent years, the adoption of alternative fuels and hybrid vehicles has necessitated radical changes to meet the energy needs of the automotive sector. Hybrid electric vehicles are used as a perfect step between traditional fossil fueled internal combustion engines and fully electric vehicles. Deeply related to this, complicated industry and manufacturers need simulation programs to reduce both the cost of test sets and to use time with the highest efficiency. Before the production, especially in automotive sector, the simulation and prototyping procedure is playing an indispensable role. For this study, the AVL-Cruise simulation tool was chosen. Due to its capability to keep up with evolving technological structures, this program can be easily implemented in hybrid vehicle simulations. In this study, a hybrid engine model was created based on a 1.5 L, four-cylinder gasoline engine and a 10 kW electric motor. Energy analysis, based on the variations in the CVT and AMT transmissions of a hybrid motor, was conducted under three different driving cycles and compared in detail. Additionally, energetic balance like exergy is executed for this model. Sankey diagrams were employed to illustrate the differences and energy consumptions of the vehicle based on the selected modeling criteria. As a result, the CVT is slightly better behaviors than AMT both fuel consumption (2.5–4%), emission reducing (1.5–4.6%) and energetic balances (3.6–5%). • Hybrid vehicles energy analyses are determined with Sankey diagrams. • Effects of CVT and AMT transmission to HEVs energetic outputs were compared. • Effects of various driving cycles on HEV components were discussed detailed. • CVT is slightly better than AMT with reducing the fuel consumption and emissions. • For this study, CVT is more energetic efficiency with 5% improvement vs AMT. [ABSTRACT FROM AUTHOR]

During the mode-switching process of a hybrid tractor equipped with a hydraulic-mechanical continuously variable transmission (HMCVT) device, the separation and combination of the clutch will cause transient shocks, affecting the smoothness and driving comfort of the entire vehicle. This article conducts simulation and experimental research on the impact problem when switching from pure electric drive mode to hybrid-power speed coupling mode. Firstly, establish a system dynamics model in SimulationX 3.5 software and build a hardware-in-the-loop (HIL) experimental platform. Secondly, a strategy of "clutch oil pressure fuzzy control + motor torque compensation" is proposed to solve the problem of the slow dynamic response of the engine. Finally, the orthogonal experiment range analysis method and variance analysis method are used to optimize the quality of mode switching, with six clutch-switching time sequences as experimental factors. The simulation results show that adopting the strategy of "clutch oil pressure fuzzy control + motor torque compensation" and optimizing the clutch-switching timing can effectively reduce the amplitude of output shaft speed reduction, dynamic load coefficient, and impact, and shorten the switching time. The comparison between the HIL test results and the simulation results shows that there is a certain difference between the two, but the overall trend is consistent, which verifies the effectiveness of the proposed control strategy and method. [ABSTRACT FROM AUTHOR]

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This paper presents a novel Continuous Variable Transmission (CVT) design. CVT is highly beneficial for actuators with rotary output as it can improve the energy efficiency of the actuators by providing an optimum transmission ratio. This property of CVT is highly beneficial for fossil-fuel-based vehicles, electric vehicles, wind turbines, industrial robots, etc. With the exception of Spherical CVT and DH CVT, all known CVTs like push belt CVTs, toroidal CVTs, Milner CVTs, etc., require additional gear sets and clutches for direction reversal and neutral gear ratio. However, Spherical CVT and DH CVT have low torque capacity due to a single traction point constraint. Foregoing in view, a new CVT named CAD CVT has been developed. The paper presents the design conception, the operating principle, the transmission ratio, the torque capacity, frictional losses, and experimental verification of the basic functionality by manufacturing a Proof of Concept (PoC). The proposed CVT is the only CVT capable of independent direction reversal and high torque capacity as it can transmit torque through multiple traction points. The new CVT will significantly impact high-torque applications in different engineering applications, especially land transport consisting of heavy vehicles like trucks, buses, and trailers. [ABSTRACT FROM AUTHOR]

: Dynamic speed can often cause the fluctuations of unmanned agricultural machines in farmland slopes. Agricultural operations can be significantly impacted, such as seeding and fertilizer application. The stability of planting and the precision of fertilizer application can depend mainly on the driving speed of driverless tractors in undulating farmland. Particularly, the absence of visual cues from the driver can lead to inevitable pre-control of the throttle when tractors operating. In this study, the robust control system of steady speed was proposed using the Digital Elevation Model (DEM). An advanced feed-forward control was also utilized at the longitudinal slopes. A systematic investigation was then made to assess the influence of farmland slope on the tractor speed. The occurrence of slope acceleration was induced by gravity during both uphill and downhill maneuvers in the tractor driving. The new control of the tractor was also used to predict the terrain slope ahead. Consequently, the speed of the tractor was adjusted for the target speed, as the terrain slope increased. An extended duration was avoided to reach the preset velocity. Alternatively, the speed readily surpassed the target speed on the decreasing slopes, resulting in frequent braking and adverse effects on the dynamics of vehicles. DEM data was utilized to extract elevation information from the terrain. The longitudinal slope feed-forward control was also introduced to dynamically obtain the prescanning distance. The pre-scanning time was configured to integrate with the current driving speed. At the same time, the slope value of the subsequent driving path was calculated to determine the compensation of speed on the slope. Ultimately, effective control of the tractor's speed was achieved to adjust the target speed in real time. The optimal performance and stability were obtained across diverse terrain gradients. DF1204 CVT tractor was taken as a test platform. Three tests were conducted with different target speeds for uphill, flat, and downhill at the Yantai Research Institute of China Agricultural University. The test results showed that when the tractor was traveling at the target speeds of 4.0, 6.0, and 8.0 km/h, the mean values of the measured speeds were 4.03, 5.94, and 7.85 km/h for uphill driving, 4.04, 6.02, and 8.03 km/h for level driving, and 4.00, 6.10, and 8.19 km/h for downhill driving, respectively. The speeds closely approached the target values, indicating the efficacy of the control system to regulate the tractor speeds. The speed accuracy was also improved with the mean speeds of the experimental group notably closer to the target speeds for both uphill and downhill driving scenarios. Moreover, the root mean square errors (RMSE) were reduced under all driving conditions, with decreases of 46.63%, 21.92%, and 37.15% for uphill, level ground, and downhill driving, respectively, compared with the control group. The speed stability was enhanced to reduce the speed fluctuations, thereby improving the overall tractor performance and operational efficiency in agricultural settings. The feedforward control of longitudinal gradient speed also surpassed the original, in terms of the speed stability and path tracking. The steady speeds with high precision were maintained in the autonomous agricultural machinery under undulating farmland environments. The tractor efficiency was then promoted to reduce the operational fluctuations in practical agricultural operations. The optimal speeds can be used to realize smoother and more productive farming in the various tasks of streamlining, such as planting and fertilization. Moreover, the operational disruptions can be minimized to maintain high-performance standards. The finding can greatly contribute to the overall quality and reliability of agricultural machine operations. Technical support can also be offered to improve agricultural productivity and sustainability in sustainable production. [ABSTRACT FROM AUTHOR]

Transmission efficiency is a key characteristic of Hydro-mechanical Continuously Variable Transmission (HMCVT), which is related to the performance of heavy-duty tractors. Predicting the HMCVT transmission efficiency is beneficial for the real-time adjustment of transmission ratio during heavy-duty tractor operations, so as to obtain better performance. Aiming at the problems of accurate method, low accuracy, and high noise in the prediction of HMCVT transmission efficiency, this paper proposes a method based on Variational Mode Decomposition (VMD), Particle Swarm Optimization (PSO), and Back Propagation (BP) neural networks to improve the quality of transmission efficiency prediction. Firstly, a simple theoretical model was established to obtain the influencing factors of transmission efficiency. Then, based on these factors, the transmission efficiency was tested on the bench under multiple conditions and the influence degree of each factor on transmission efficiency was divided using Partial Least Squares (PLS) method. Finally, the VMD method was used to denoise the test data, and a BP model, which was improved using the PSO method, was established to predict the processed data. The results showed that transmission efficiency of HMCVT is most affected by output speed, followed by power, and least by input speed. The VMD method can accurately extract effective signals and noise signals from the original data, and reconstruct signals, reducing the noise proportion. Using three conditions, the prediction regression accuracy of the PSO–BP model is 7.02%, 7.88%, and 9.26% higher than that of the BP model, respectively. In the three prediction experiments, the maximum differences in the MAE, the MAPE, and the RMSE of the PSO–BP model are 0.002, 0.463%, and 0.004, respectively, which are 0.006, 0.796%, and 0.003 lower than those of the BP model. [ABSTRACT FROM AUTHOR]

Twisted string actuators, which are an emerging artificial muscle, efficiently convert rotary motor motion into linear load movement, with advantages like high transmission ratio, compliance, simple structure, and long-distance power transmission. However, the limited range of transmission ratio adjustment remains a challenge. Thus, this paper introduces a novel twisted string actuator design that automatically and continuously adjusts its transmission ratio in response to external loads. Utilizing lightweight hyperelastic slender rods, the twisted string actuator with continuously variable transmission achieves a simple, compact, and cost-effective design. By manipulating the distance between two twisted strings through rod deformation, the transmission ratio continuously adapts to varying load conditions. Mathematical models of the twisted string actuator with continuously variable transmission are derived and experimentally validated, demonstrating a 2.1-fold transmission ratio variation from 0.1 kg to 1.5 kg loads. Application in an anthropomorphic robot finger showcases a 6.2-fold transmission ratio change between unloaded and loaded states. Our twisted string actuator with continuously variable transmission offers unparalleled advantages in weight, cost, simplicity, compliance, and continuous transmission ratio adjustability, making it highly suitable for robotic systems.

In this study, a design method of driving controller based on nonlinear model predictive control (NMPC) is presented for internal-combustion-engine (ICE) vehicles equipped with continuously variable transmissions (CVTs). The clutch-engaged and -released modes and engine-on and -off modes are considered, along with the engine-braking effect. The switching characteristics of the vehicle system dynamics are relaxed into continuous transitions. This allows for the use of standard NMPC software packages to solve the NMPC problem. Numerical examples indicate that the designed controller is capable of achieving real-time driving control based on NMPC.

The large majority of electric cars have a single-speed gearbox, because electrified powertrains provide maximal power across a wide operating range, and single-speed simplifies construction and reduces capital costs. Nevertheless, multi-speed transmissions have also been developed for electric cars, and some of them have recently appeared as commercial products. This paper aims to compare, through some practical examples, solutions with single-speed and dual-speed transmissions. In particular, given the very smooth driving of electric cars, for dual-speed solutions, a dual-clutch gearbox was considered. Finally, a continuously variable transmission (CVT) was also used. Different solutions were analyzed from a technical–economic point of view, based on a simulation of the vehicle under standardized driving cycles, thus evaluating the capital and running electricity costs. The obtained results show that the comparison between the two solutions is very open, and in the majority of cases, the advantages in terms of efficiency overcome the disadvantages due to the additional capital costs. For a rather low battery cost of 150 €/kWh, the total cost reduction moves from about 100–150 € up to 1500–2000 €, depending on the electricity cost, along the whole vehicle lifespan. [ABSTRACT FROM AUTHOR]

Pipelines are embedded in industrial sites and residential environments, and maintaining these pipes is crucial to prevent leakage. Given that most pipelines are buried, the development of robots capable of exploring their interiors is essential. In this work, we introduce a novel in-pipe robot utilizing Continuously Variable Transmission (CVT) mechanisms for navigating various pipes, including vertical and curved pipes. The robot comprises one air motor, three CVT mechanisms, and six wheels at the end of six slider-crank mechanisms, including three active and three idler ones. The slider crank and spring mechanism generate a wall press force through the wheel to prevent slipping inside the pipe. This capability allows the robot to climb vertical pipes and adapt to various pipe diameters. Moreover, by combining CVT mechanisms, whose speed ratios between the driver and driven pulleys are passively adjusted by the position of the slider, the robot achieves independent and continuous speed control for each wheel. This enables it to navigate pipes with various geometries, such as straight–curved–straight pipes, using only one motor. Since active control of each wheel is not needed, the complexities of the robot controller can be significantly reduced. To validate the proposed mechanism, MATLAB simulations were conducted, and in-pipe driving experiments were executed. Both simulation and experimental results have shown that the robot can effectively navigate curved pipes with a maximum speed of 17.5 mm/s and a maximum traction force of 56.84 N. [ABSTRACT FROM AUTHOR]

In order to analyze the vibration mechanism of a metal belt continuously variable transmission, the nonlinear torsional dynamic model of two-stage planetary gear is established by using the lumped parameter method. The dynamic response is solved by using the fourth-order Runge-Kutta method. The dynamic simulation is carried out by using ADAMS software. The dynamic response is verified and the CVT shaking table test is carried out.The results show that the fourth-order runge-kutta method is basically consistent with the dynamic response results obtained by ADAMS dynamic simulation. The bench test results show that when the forward speed is 2500 r/min, the maximum vibration acceleration at the axial position of the input shaft of the low-speed gear is 0.623 m/s², and when the speed is 1000 r/min, the maximum acceleration at the axial position of the input shaft of the low-speed gear is 0.309 m/s2 . Under the condition of reverse gear, when the rotational speed is 2500 r/min, the maximum vibration acceleration of the axial position of the reverse gear input shaft is 0.703 m/s² . When the rotational speed is 1000 r/min, the maximum acceleration of the axial position of the reverse gear input shaft is 0.504 m/s² . The amplitude of vibration acceleration under reverse gear condition is 12.85 % higher than that under forward gear condition. The vibration signals of 54.4 and 108.8 orders in the reverse gear order spectrum are the most obvious. The increase of the meshing times and the meshing clearance of the two-stage planetary gear during the gear shifting process are the main reasons for the increase of the vibration of CVT in the reverse gear power [ABSTRACT FROM AUTHOR]

The aim of this paper is to assess the performance parameters of the cam-type pulse continuously variable transmission, which is a first attempt to investigate this issue in the presented manner. The transmission under investigation comprises two cams in cooperation with two units, each consisting of rollers connected to swing rods mounted on overrunning clutches. To accomplish this, a test stand was built and a detailed testing program was developed takes into consideration the influence of gear ratio, rotational speed, and load on the uniformity of motion and efficiency. Analysis of the obtained results leads to the conclusion that the tested transmission is particularly sensitive to changes in operating conditions, and its overall performance deteriorates as the reduction ratio increases. The best results were achieved with a load below the nominal one, at low rotational speeds and a low speed reduction. The transmission's structure design and operational principle result in significant power losses, as evidenced by an efficiency rating of less than 60%. [ABSTRACT FROM AUTHOR]

The multi-degree-of-freedom characteristics of the planetary gear electronic continuously variable transmission (ECVT) configuration in series-parallel hybrid tractors impose more complex requirements for energy management strategies under variable load conditions. For a high-power hybrid tractor, this paper takes the hybrid tractor output-split (OS)-ECVT configuration as the research object and describes the principles of stepless transmission and power-splitting within the configuration. In order to improve the fuel economy of high-power hybrid tractors and the running status of power components, an energy management strategy focused on ploughing conditions based on the Bellman minimum dynamic programming (DP) algorithm is proposed in this paper. Second, equivalent fuel consumption is selected as the performance index for energy-saving control, and the solving principle of the energy management strategy based on the dynamic programming algorithm is established to facilitate the resolution process of the energy management strategy. Finally, the energy-saving control simulation is completed under ploughing conditions. The results show that compared with the energy management strategy based on the optimal operating line (OOL), the energy management strategy based on DP fully utilizes the benefits of low-cost electric energy and enables the hybrid power system to have a wider range of stepless transmission performance. In addition, the hybrid power system has the advantages of enhanced decoupling of speed and torque, higher efficiency, and more economical secondary energy conversion. As a result, the whole machine has enhanced power-split performance, greatly improving the running conditions of the power components. The equivalent fuel consumption values of the energy management strategies based on DP and OOL are about 3.1238 L and 4.2713 L, respectively. The equivalent fuel consumption based on DP is reduced by about 26.87%, which effectively improves the fuel efficiency of hybrid tractors.

Climate change and air pollution are two significant challenges facing our society and represent a major driver for new developments in the transport sector. As a consequence, automotive manufacturers have focused on the electrification of vehicle propulsion systems and offer a wide range of hybrid and full-electric vehicles in different classes. However, in the world's most densely populated metropolitan areas, small and lightweight vehicles are key for the mobility of millions. Traditionally these vehicles have provided cost-effective transportation which is difficult to preserve with vehicle electrification. Many of these light vehicles, such as scooters and all-terrain vehicles, use internal combustion engines in combination with a continuously variable rubber belt transmission which provides a simple, comfortable and cost-effective transmission technology but with poor efficiency and high maintenance costs. In this contribution, a novel full hybrid powertrain concept is proposed that offers a similar driving experience to conventional continuously variable transmissions while providing significantly improved performance and fuel economy combined with low system complexity. In its basic configuration, the hybrid powertrain can operate without active actuators and even with mechanical throttle control of the internal combustion engine. This minimalist approach reduces system costs and helps to create a competitive solution for price-sensitive markets. The hybrid system is based on a planetary gear set that combines the internal combustion engine and an electric motor. It is complemented by a centrifugal clutch and one-way clutch, resulting in different operating modes for low and high speeds as well as for electric driving. This paper describes the mechanical design and control approach of the proposed hybrid powertrain layout. In order to evaluate the basic functionalities, a prototype vehicle was built and tested. This contribution shows the integration of the hybrid powertrain concept in a prototype vehicle and proves the fulfilment of all required full hybrid functionalities. [ABSTRACT FROM AUTHOR]