Error in applying tensorrt_optimized model in driveworks-0.6 ./sample_object_detector


I got this error when I trying to apply the sample optimized model in sample_object_detector. Could you help me with this error?

./sample_object_detector --tensorRT_model=../../driveworks-0.6/data/samples/detector/optimized.bin
Program Arguments:

nvrm_gpu: Bug 200215060 workaround enabled.
Initialize DriveWorks SDK v0.6.67
Release build with GNU 4.9.2 from v0.6.0-rc7-0-g51bd3aa against Vibrante PDK v5.0.5.0
TimeSource: monotonic epoch time offset is 1526408382694795
TimeSource: PTP ioctl returned error. Synchronized time will not be available.
TimeSource: Could not detect valid PTP time source at 'eth0'. Fallback to CLOCK_MONOTONIC.
SDK: Resources mounted from /usr/local/driveworks-0.6/data/resources
SDK: Create NvMediaDevice
SDK: use EGL display as provided
SDK: number of GPU devices detected 2
SDK: currently selected GPU device discrete ID 0
SAL: identified board as DrivePX2-TegraA
SensorFactory::createSensor() -> camera.virtual, video=.././data/samples/sfm/triangulation/video_0.h264,yuv2rgb=cuda
CameraNvMedia: no seek table found at .././data/samples/sfm/triangulation/, seeking is not available.
Camera image with 1280x800 at 30 FPS
nvmEglStProducerCreateCommon: Entered
nvmEglStProducerCreateCommon: Entered
Initializing TensorRT Network: ../../driveworks-0.6/data/samples/detector/optimized.bin
sample_object_detector: cudnnEngine.cpp:640: bool nvinfer1::cudnn::Engine::deserialize(const void*, std::size_t, nvinfer1::IPluginFactory*): Assertion `size >= bsize && "Mismatch between allocated memory size and expected size of serialized engine."' failed.
Aborted (core dumped)