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Abstract(s)
Com a necessidade crescente da produção de automóveis, gerada pelo aumento populacional em junção com as tentativas de inovação e introdução de novas tecnologias na indústria automóvel, verifica-se um surto de novas funcionalidades disponibilizadas ao consumidor. A maioria destas têm como principal foco a segurança rodoviária, uma preocupação em crescimento dado que mais pessoas circulam nas estradas públicas diariamente, aumentando as chances de possíveis acidentes. Algumas das funcionalidades que vêm a surgir incluem, por exemplo, aviso de colisão, deteção de ângulo morto e assistência à mudança de faixa, um conjunto de funcionalidades com grande dependência de sistemas de deteção. Atendendo a que alguns sistemas de deteção já são considerados comuns em veículos, para auxílio ao estacionamento, por exemplo, o conceito não é novo, mas os sistemas já existentes apresentam limitações quanto ao clima, alcance e resolução, entre outros. Para ultrapassar estas dificuldades, a indústria automóvel iniciou a implementação de sistemas baseados em radar. A tecnologia radar é capaz de cobrir a maioria das necessidades da indústria automóvel para sistemas de deteção e, considerando o foco acrescido que tem sido dado pelos fabricantes automóveis aos sistemas avançados de auxílio à condução (ADAS), outras tecnologias são também consideradas e usadas em junção com o radar, como é o caso do LiDAR, uma solução com custos mais elevados e mais apropriada para desenvolvimentos na área dos veículos autónomos e não tanto para os veículos orientados ao consumidor. Com o crescimento da procura por radares automóveis, os fabricantes dos mesmos procuram também sistemas de testes para os seus produtos. Tendo em conta o potencial do mercado do radar automóvel, múltiplos desenvolvedores de testadores procuram uma forma de incorporar testadores de radar nas fábricas dos seus clientes, um desafio para este tipo de sistemas. Para cumprir com as normas europeias de teste, um engenheiro de testes deverá encontrar complicações com o tamanho da câmara anecoica necessária para realizar os testes, assim como as larguras de banda necessárias. As dimensões elevadas da câmara anecoica aumentam o testador para tamanhos inapropriadas à inserção em linhas de produção e a solução, tipicamente, requer ignorar as indicações ergonómicas para operação do sistema, um problema por si só. Para ultrapassar este problema, este documento propõe uma solução automatizada para deslocamento da unidade, disponibilizando posições ergonómicas e reduzindo as dimensões da máquina. Apesar do quão vantajosas sejam estas funcionalidades, este tipo de implementação adiciona complexidade ao sistema, dificultando o desenvolvimento e aumentando o custo para o cliente final. Apesar do desagradável aumento no preço, o tamanho mais compacto e a conformidade com as normas europeias são razões suficientes para considerar este tipo de sistema de teste em detrimento de outros. Para validar o conceito do testador, o mesmo deve ser capaz de gerar objetos para o radar detetar durante o teste num ambiente de espaço aberto simulado, como numa câmara anecoica blindada. Para simular estes objetos, é necessário utilizar um gerador de objetos radar, um dispositivo capaz de ser colocado próximo do radar e de gerar objetos mais distantes. Este é também essencial para garantir que a totalidade da largura de banda da unidade é testada, sendo que tipicamente estão disponíveis nas duas larguras mais usadas nos radares automóveis: 76-77 GHz e 77-81 GHz. Neste documento, os radares AWR1642 da Texas Instruments e o ARS408-21 da Continental são utilizados para validação do testador. Alguns testes iniciais são necessários em bancada de teste onde é expectável maior ruído e um rácio signal-to-noise pior. Outros testes deverão ser realizados com os restantes componentes do testador, como a espuma absorbente de RF, a câmara anecoica blindada e o gerador de objetos radar. Deverão ser identificadas melhorias em cada fase e, em última instância, o comportamento no interior do testador deverá ser claramente superior aos testes iniciais.
The rising need for more cars to be produced, induced by the population growth, allied to the attempts at innovation and introduction of new technologies in the automotive industry, originated the surge of new features available to the consumer. Most of these are road safety focused, a growing concern as more people circulate in the public roads daily, increasing the likelihood of accidents. Some of those features include, for example, collision warning/prevention, blind-spot detection and lane-change assist, a group of features which rely heavily on detection systems. With some forms of detection systems already common in vehicles, for parking assistance, for instance, the concept isn’t new, but the existing systems have limitations related to weather, range and resolution. To overcome these issues, the automotive industry implemented detection systems based on radar. Radar covers most needs in the automotive industry for detection systems and, as such, becomes a growing presence in cars, being a core component in new and improved features. Having advanced driver assistance systems (ADAS) become such a major focus for cars developers and manufacturers, some other technologies are also considered and implemented in conjunction, like LiDAR, a more expensive solution, best suited for autonomous driving development and not consumer-focused vehicles. As the demand for automotive radars rises, so does the demand for radar test systems by the manufacturers. Considering the potential growth for the automotive radar market, multiple tester developers are focusing in the most efficient way to incorporate such a tester into their clients manufacturing plants, a challenge for this type of systems. A test engineer who wishes to comply with the European standards for automotive radar testing faces complications with the required anechoic chamber size where the tests will be carried out and the frequency bandwidths required. Its large dimensions tend to grow the test system into sizes not suited for a manufacturing plant and the solution is typically to disregard ergonomic guidelines for the system operation, an issue in itself. To overcome the size issue, this paper presents a proposed solution based on automated unit transposing, allowing for the operator to work in ergonomic positions and for the machine to reduce in size. As advantageous as these features may be, this type of implementation adds complexity to the system, increasing the difficulty in development and the cost for the final client. Despite the non-appealing increase in price, the more compact size and standard compliance, are enough reasons to consider the system over others. In order to assure the concept for the tester is a valid one, the tester must be capable of generating targets for the radar sensor under test to detect in an emulated open-space environment, i.e. inside a shielded anechoic chamber. The objects generated must cover most of the sensor’s range, which can typically reach the hundreds of meters. To emulate these objects, a radar echo generator must be used, a device capable of being placed close to the radar sensor and generating targets further away. These devices are also the core component to assure the entirety of the radar frequency bandwidth is tested, as they are usually available in the two most used in automotive radar: 76-77 GHz and 77-81 GHz. To test the correct functioning of the system, a radar sensor must be inserted in the system and its data analysed, throughout the entirety of development. For this paper, the Texas Instruments’ AWR6142 and Continental’s ARS408-21 radar sensors are used to evaluate the tester performance. Some initial tests must be carried out in a testbench where clutter and a worse signal-to-noise ratio are expected. Some other tests must then be done with the gradual introduction of tester components, i.e. RF absorbent foam, shielded anechoic chamber and radar echo generator. Improvements must be seen in each phase and, ultimately, the performance inside the full tester must be clearly superior to the initial tests.
The rising need for more cars to be produced, induced by the population growth, allied to the attempts at innovation and introduction of new technologies in the automotive industry, originated the surge of new features available to the consumer. Most of these are road safety focused, a growing concern as more people circulate in the public roads daily, increasing the likelihood of accidents. Some of those features include, for example, collision warning/prevention, blind-spot detection and lane-change assist, a group of features which rely heavily on detection systems. With some forms of detection systems already common in vehicles, for parking assistance, for instance, the concept isn’t new, but the existing systems have limitations related to weather, range and resolution. To overcome these issues, the automotive industry implemented detection systems based on radar. Radar covers most needs in the automotive industry for detection systems and, as such, becomes a growing presence in cars, being a core component in new and improved features. Having advanced driver assistance systems (ADAS) become such a major focus for cars developers and manufacturers, some other technologies are also considered and implemented in conjunction, like LiDAR, a more expensive solution, best suited for autonomous driving development and not consumer-focused vehicles. As the demand for automotive radars rises, so does the demand for radar test systems by the manufacturers. Considering the potential growth for the automotive radar market, multiple tester developers are focusing in the most efficient way to incorporate such a tester into their clients manufacturing plants, a challenge for this type of systems. A test engineer who wishes to comply with the European standards for automotive radar testing faces complications with the required anechoic chamber size where the tests will be carried out and the frequency bandwidths required. Its large dimensions tend to grow the test system into sizes not suited for a manufacturing plant and the solution is typically to disregard ergonomic guidelines for the system operation, an issue in itself. To overcome the size issue, this paper presents a proposed solution based on automated unit transposing, allowing for the operator to work in ergonomic positions and for the machine to reduce in size. As advantageous as these features may be, this type of implementation adds complexity to the system, increasing the difficulty in development and the cost for the final client. Despite the non-appealing increase in price, the more compact size and standard compliance, are enough reasons to consider the system over others. In order to assure the concept for the tester is a valid one, the tester must be capable of generating targets for the radar sensor under test to detect in an emulated open-space environment, i.e. inside a shielded anechoic chamber. The objects generated must cover most of the sensor’s range, which can typically reach the hundreds of meters. To emulate these objects, a radar echo generator must be used, a device capable of being placed close to the radar sensor and generating targets further away. These devices are also the core component to assure the entirety of the radar frequency bandwidth is tested, as they are usually available in the two most used in automotive radar: 76-77 GHz and 77-81 GHz. To test the correct functioning of the system, a radar sensor must be inserted in the system and its data analysed, throughout the entirety of development. For this paper, the Texas Instruments’ AWR6142 and Continental’s ARS408-21 radar sensors are used to evaluate the tester performance. Some initial tests must be carried out in a testbench where clutter and a worse signal-to-noise ratio are expected. Some other tests must then be done with the gradual introduction of tester components, i.e. RF absorbent foam, shielded anechoic chamber and radar echo generator. Improvements must be seen in each phase and, ultimately, the performance inside the full tester must be clearly superior to the initial tests.
Description
Keywords
Radar automóvel Sistema de testes ADAS RCS Ergonomia AREG100A Testador ETSI Automação Gerador de objetos radar Linha de produção Laboratório Automotive radar Test system ErgonomicAutomation Tester Radar target generator Production-line Laboratory