Kim Seong Han, Lee Kang In
School of Intelligent Mechatronics Engineering, Sejong University, 209 Neungdong-ro, Gunja-dong, Gwangjin-gu, Seoul 05006, Korea.
R&H Research Lab, Hyundai Motor Company, 150, Hyundaiyeonguso-ro, Namyang-eup, Hwaseong-si, Gyeonggi-do 18280, Korea.
Sensors (Basel). 2020 Mar 16;20(6):1648. doi: 10.3390/s20061648.
Vehicle wheel alignment inspection is generally carried out using a computer vision-based system. Due to its inspection mechanism using four wheel centers, the computer vision-based system cannot be applied to the wheel alignment inspection of suspension module units. However, when a vehicle suspension module is being developed, there is no complete car ready for wheel alignment inspection even though it is a very important procedure for suspension property tests. This study proposes a novel and efficient way to inspect vehicle wheel alignment for suspension modules. Two laser modules and several mechanical jigs were employed for wheel alignment inspection, allowing the toe and camber angles of the suspension module to be measured. For accurate wheel alignment results, calibration of the laser modules was performed prior to the inspection. This calibration procedure adjusts the yaw and pitch angles of the laser module so that they can be orthogonal to the mounting jig. For the calibration, a novel method of using laser straightness was adopted and, consequently, 0.02 degrees of orthogonality was achieved. The wheel alignment inspection results were determined then verified using a vision system with two cameras. In order to use this vision system, two cameras were used and a new method of modifying the measurement mechanism was developed. According to the verification results, the proposed wheel alignment inspection provided very high measurement accuracy. The wheel alignment inspection mechanism proposed in this study can not only give very reliable results but also provide a cost-efficient method of inspecting the wheel alignment of suspension modules to automakers.
车轮定位检查通常使用基于计算机视觉的系统来进行。由于其基于四轮中心的检查机制，基于计算机视觉的系统无法应用于悬架模块单元的车轮定位检查。然而，在开发车辆悬架模块时，即使车轮定位检查对于悬架性能测试是一个非常重要的程序，也没有完整的车辆可用于此项检查。本研究提出了一种新颖且高效的方法来检查悬架模块的车轮定位。采用了两个激光模块和几个机械夹具进行车轮定位检查，从而能够测量悬架模块的前束角和外倾角。为了获得准确的车轮定位结果，在检查之前对激光模块进行了校准。该校准程序调整激光模块的偏航角和俯仰角，使其能够与安装夹具正交。在校准过程中，采用了一种利用激光直线度的新颖方法，从而实现了0.02度的正交度。然后确定车轮定位检查结果，并使用具有两个摄像头的视觉系统进行验证。为了使用该视觉系统，使用了两个摄像头，并开发了一种修改测量机制的新方法。根据验证结果，所提出的车轮定位检查具有非常高的测量精度。本研究中提出的车轮定位检查机制不仅能够给出非常可靠的结果，而且为汽车制造商提供了一种经济高效的悬架模块车轮定位检查方法。
