Power Switch ON FPGA Program ON Console and Monitoring Device Are OK? Main Program ON Yes No Repair Console Input Safe Mode ON Speed and Force Limitation ON Power-Control Circuit OFF Power-Control Circuit ON No Repeat Five Times? No Error Alarm Electric Power Is OK? Yes Yes Yes Error Alarm No Error Alarm Battery Capacity Is Sufficient? No Error Alarm Motor Drivers Are OK? Yes No Error Alarm Sensor System Is OK? Console Input Safe Mode OFF/ Locomotion Mode ON Speed and Force Limitation OFF Console Input Locomotion Stop Locomotion in Real Environment * Battery Capacity * Electric Power * Motor Driver * Sensor System * Console * Monitoring Device Fault? No Yes Emergency Mode ON Power-Control Circuit OFF Main Control Program OFF Start-up Mode Safe Mode FPGA Program OFF Locomotion Mode Power Switch OFF Shutdown Mode Figure 4. The overall program processes consist of start-up mode, safe mode, locomotion mode, and shutdown mode. 80 * IEEE ROBOTICS & AUTOMATION MAGAZINE * DECEMBER 2017