Study of drive systems on underwater robot joint motor

HE Lei， XV Guo-hua， LIU Ya-ping
（School of Naval Architecture and Ocean Engineering， Huazhong University of Science and Technology，
Wuhan 430074， China）

Abstract： Aiming at the large volume and high power dissipation problems of the underwater robot joint motor drive system，according to analysis of the principle and architecture of the system，methods of high integrity devices，small packages，multi-layer PCBs，low-power devices，power management etc. were presented to reduce its volume and power dissipation. An underwater brushless DC（BLDC）motor drive system was developed，including a drive circuit，control algorithms and a control interface，area and power dissipation of the circuit were measured and speed servo experiment was made. The results indicate that，the area of the drive circuit is reduced to only 8.2 cm2，which enables the circuit to be placed into the motor directly. Static and dynamic power dissipation of the drive circuit are 0.24 W and 0.5 W respectively，which satisfy the power dissipation requirement of underwater operation. When placed into the manipulator and given a 120 r/min reference speed，the motor can track the reference speed in less than 1 s steadily and accurately，which shows that it can perform the underwater operation task.
Key words： underwater robot； joint motor； brushless DC（BLDC）motor； drive system