Data Acquisition Device (DAQ) is an electronic component used in formula student vehicles. To optimize the performance of the formula student vehicle and its driver, it is necessary to analyze and ...monitor the data acquisition system. Parameters acquired on the car include the position of the brake pedal/throttole and wheel speed.DAQ system has 5 input channels namely 3 analog input pins and 2 digital input pins, and 3 output channels, which is the controller pin, fault pin, and brake light pin. The DAQ system in this research is designed and made using Teensy 3.6, a signal conditioning circuit consisting of an RC low pass filter, voltage follower, non-inverting amplifier, and logic level shifter. DAQ system uses CANBUS to read and process sensor data. DAQ system can acquire data from the KTC Linear Motion Position sensor PZ-12-A-50P with an accuracy value of 99,91%; Hall-effect Rotary Position sensor RTY120LVNAX with an accuracy value of 99,94% for both the first and second sensors; and Proximity sensor LJ12A3-4-Z/BX with an accuracy value of 99,58% for the first sensor and 99,46% for the second sensor. DAQ is able to run controller signal processing, detect faults, and activate brake light signal according to FSAE rules.
The ways to reduce the number of wires suitable for the main control unit were considered. A block diagram of the algorithm of actions of the created special device is proposed, which allows ...minimizing the number of wires. The format of CAN-messages containing data from all polled sensors and an electrical circuit diagram is presented. A general view of the developed device is presented, which made it possible to reduce the number of signal wires running through the entire vehicle to two pieces.
The proliferation of electric vehicle (EV) technology is an important step towards a more sustainable future. In the current work, two-layer feed-forward artificial neural-network-based machine ...learning is applied to design soft sensors to estimate the state of charge (SOC), state of energy (SOE), and power loss (PL) of a formula student electric vehicle (FSEV) battery-pack system. The proposed soft sensors were designed to predict the SOC, SOE, and PL of the EV battery pack on the basis of the input current profile. The input current profile was derived on the basis of the designed vehicle parameters, and formula Bharat track features and guidelines. All developed soft sensors were tested for mean squared error (MSE) and R-squared metrics of the dataset partitions; equations relating the derived and predicted outputs; error histograms of the training, validation, and testing datasets; training state indicators such as gradient, mu, and validation fails; validation performance over successive epochs; and predicted versus derived plots over one lap time. Moreover, the prediction accuracy of the proposed soft sensors was compared against linear or nonlinear regression models and parametric structure models used for system identification such as autoregressive with exogenous variables (ARX), autoregressive moving average with exogenous variables (ARMAX), output error (OE) and Box Jenkins (BJ). The testing dataset accuracy of the proposed FSEV SOC, SOE, PL soft sensors was 99.96%, 99.96%, and 99.99%, respectively. The proposed soft sensors attained higher prediction accuracy than that of the modelling structures mentioned above. FSEV results also indicated that the SOC and SOE dropped from 97% to 93.5% and 93.8%, respectively, during the running time of 118 s (one lap time). Thus, two-layer feed-forward neural-network-based soft sensors can be applied for the effective monitoring and prediction of SOC, SOE, and PL during the operation of EVs.
Abstract The study concerns the life cycle assessment (LCA) of a prototype electric racing car, Formula Student, developed by students of the Poznan University of Technology under the name of eVarta. ...The main objective of this study is to identify critical environmental points and indicate key elements of the vehicle's life cycle, along with the impact of the assumptions made. In the first part of the work, a literature review and standard review are conducted to organise the information and methodological steps for the LCA components and their application in the subsequent stages of the study. The work focusses on defining the right assumptions, the process of data collection and its appropriate aggregation, as well as the creation of a functional structure for the object under study. SimaPRO software is used to perform the assessment. The results of the evaluation show the high importance of the vehicle transportation stage in the entire life cycle and the significant impact of the transport-related processes, mostly considering the fact that the eVarta is a concept racing car, used only in specific conditions of Formula Student races around the world. Most of the distances between races are covered using external transport means, and eVarta is used only for racing. The second main source of environmental impacts is related to the use of resources associated with the production of the high-voltage traction battery and the use of aluminium and related processes. eVarta is a custom concept race car, designed and built by the team of students from different faculties at Poznan University of Technology (Poland). As a prototype, eVarta demonstrates high levels of environmental burden related to the production of materials and techniques. The proportion of these impacts may be limited by using a 3D CAD model to improve the information flows regarding the production of all parts. Moreover, the reduction of the environmental impacts may be reached by: (a) enhancement of production of traction battery, (b) substitution of construction materials, and (c) improvements during use, e.g. implementation of energy recovery systems during braking. Graphical Abstract
The current impact attenuator used by the Formula Student team of University of Lisbon is an out-of-shelf solution consisting in an aluminum honeycomb. The competition regulations defined for the ...impact attenuator's design allow room for innovation, which can be used to build more efficient structures and explore new materials. The main objective of this work is to design and optimize a composite impact attenuator lighter than the solution currently used by the team. Experimental results and numerical models presented in previous works are considered in the development of a new approach. Several design parameters are studied and their influence on the behavior of the impact attenuators are taken into account. Direct Multisearch (DMS) algorithm directly coupled to Abaqus software is used to perform the optimizations. The lighter solutions' mass is compared to the baseline aluminum structure's and detailed descriptions are presented for chosen optimal designs, which constitute an improvement regarding the baseline's mass.
Composite sandwich structures are widely used in transport and energy applications because of their excellent specific strength and fatigue damage resistance. However, the mechanical properties of ...the joint area rely on the structural design. This paper proposes a novel carbon fiber-reinforced polymer sandwich joint in the context of a Formula Student monocoque. A stiffener is introduced to connect carbon fiber panels on both sides, and the geometry of the aluminum honeycomb connecting core is adjusted to improve the stress distribution in the joint panels. A finite element model under a three-point bending load is established based on the progressive damage model and the cohesive zone model. The mechanical properties were compared with conventional joints based on Formula Student three-point bending tests. Specimens were fabricated and tested using t700 carbon fiber prepreg and 3003 aluminum honeycombs to verify the joint’s performance and the accuracy of the finite element model. Experimental results showed that the three-point bending strength of the novel joint increased by 52.27
%
, and the stiffness increased by 101
%
compared to the conventional design. The simulated strength errors of the novel joint and the conventional joint were 4.66
%
, and 13.7
%
, respectively, and the failure modes were consistent with the experimental results, indicating the validity of the finite element model. The novel joint profile is less protruding than the conventional joint and could be widely used for joining or repairing automotive and aircraft components.
This paper deals with the design of an upright using a topological optimization. This type of optimization is a relatively young and rapidly evolving area of computational mechanics that seeks to ...make multiple material savings that cannot be achieved by conventional methods. The optimized upright was utilized in a fully functional prototype of the student formula within the Formula Student competition. The main objective of the optimization was to meet the requirements of the physical properties, weight, stiffness, and strength of the upright. The initial model of the upright was iteratively optimized using topological optimization and a finite element static analysis to obtain the final model. Using the finite element analysis, its behavior in operation within individual load cases was predicted. Symmetry was used to mirror the finished model to obtain the opposite upright of the other side of the car. Finally, the topologically optimized upright was compared with an upright made by conventional methods.
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