You only need a router if you connect via infrastructure (connected to your network via the router) otherwise you can connect adhoc (or AP mode....directly to your PC)... So the answer is depending on the way you connect you don't necessarily need a router....

im very confuse about the EZB4 because it is called "Brain of the EZ-Robot" ... if it is the brain of the robot why do i still need to use a computer/laptop for processing the data came from sensors as input and to output like servos for robotic arm etc... because like human brain it is capable of storing data and processing data... my question is why it is called brains of EZ-robot?

The ezb4 controls your robot, sends back sensor data to the PC..... Then the PC (ARC) uses that data and tells the EZB4 what to do and when to do it... So basically the EZB4 is the PCs eyes, hands, legs, ears, mouth etc.... The PC is the boss and the EZB4 is the worker... Remember a PC can process information many, many times faster than the EZB4 can... but the PC is too big, too heavy, too power hungry and doesn't have that much in the way of sensor or servo ports, etc... ... If you put your laptop on your robot, how are you going to plug in servos, ping sensors, IR sensors, motors etc? So using the EZB gives you the next best thing... small, light, low power but with the processing help of a PC...

By the way, without a PC you wouldn't have a camera or voice control...

Welcome to the way that robotics is going. Even the Rapiro (which is a very limited robot) uses this model. It has a controller board and a processor board. All of the robots that are considered powerful today use this model. The thing that sets the ez-b apart is that it gives you the option to use either a remote computer or an on board computer connected via wifi. This let's you decide where the computer will be.

If the computer is on board, I wouldn't use a router. If the robot will always be near the computer, I wouldn't use a router. If the robot will be able to move autonomously throughout a building, I would use a router. If the robot needs to be able to be connected to from other locations outside the building, I would use a router but there are ways around using a router. If you are taking your robot around to areas that either dont have a wifi network or you dont have access to their wifi network, you could use your own router or run the robot without a router.

The choice is yours and depending on what the robot is doing, you might need to use a router, or might not have access to a router.

I would say that the ez-b is more like the brain stem of the robot.

The Learn section has videos how to connect in either wifi mode.

thank you guys!