Internal batteries

This page explains about the power supply of the robot. The robot has three battery systems. They are for control circuit, servomotors and radio receiver.
I am always using Ni-MH battery and Ni-Cd battery because of following characteristics.
• They are easy to get.
  
• They are not expensive.
  
• Their running cost is low.
  
• They have enough current capability for the robot.
  

  This picture shows Ni-MH batteries. 8.4V 120 mAh, 4.8V 550 mAh(1.2V * 4), 4.8V 1300 mAh(1.2V * 4).

  [Control] [Actuators] [RC receiver]

For the control circuit

Configuration 1: A switching regulator supplies 5V stabilized current. Output capability of the regulator is 6A.
Configuration 2: Ni-Cd battery (7.2 V 1400 mAh) supplies power and it is stabilized with regulator IC 7805.
Configuration 3: Ni-MH battery (8.4 V 120 mAh) supplies power and it is stabilized with regulator IC 7805.

For the actuators

4.8 V 1300 mAh Ni-MH battery supplies power to the servomotors. The output current is not stabilized. The servomotors cannot generate MAX torque but it is enough for the robot. The robot can walk about half an hour with this battery.

For the RC receiver

Four AAA batteries supply power to the receiver. The output is not stabilized. The circuit around the receiver is separated from control circuit to avoid interference of digital noise.