newbie clawbot problem

VEX V5 General Discussion Technical Discussion
#1

Good Morning. I bought the Clawbot starter kit for my son. we assembled the kit as per instructions. When we turn on the cortex, the motors all continuously rotate. So we shut off the Cortex and did the “Getting started” first program. On trying to load it into the Cortex we were told to upgrade the firmware, so we did that. The program seemed to load, however the robot behavior remains the same.

Any ideas where we have gone wrong?

Of note:

  1. the instructions seem to ask for a USB to serial adaptor. We only received a USB to USB cable in our kit. The cortex has a usb connector on it. This is what we have used.

  2. When first turning on the device, all the motors want to continually rotate. the motors are plugged in as follows:
    -left motor into motor port 3
    -right motor into motor port 4
    -arm motor into motor port 7
    -claw motor into motor port 6

Of interest, the clawbot assembly instructions show the left motor in port 1 and the right motor in port 10, however the “getting started” instructions say 3 and 4 respectively.

Either way, upon powering up, all motors want to rotate continuously.

We wrote the first getting started program as follows:
void main ( void )
{

SetMotor ( 2 , 127 ) ;

Wait ( 3000 ) ;

SetMotor ( 2 , 0 ) ;

}

Very simple. We plugged in the USB cable to the cortex and the computer, hit the build and download button. We were prompted to upgrade the firmware, which we did. We then hit the build and download button again. Received confirmation that all completed properly, powered up the robot, and once again, the motors all simply spin.

Any help? I sure would like this to work for my son who is 12 years old and very interested in autonomous programming. BTW, this is fully autonomous, no joystick.

Many thanks in advance

#2

The product page says that the clawbot kit only comes with two MC29s (motor controllers), this means that two of the motors should probably be in ports 1 & 10 which can control the motors directly. If you have any two wire motors directly connected to ports 2 through 9 without using an MC29 then turn of the cortex and remove them before damage occurs. Ports 2 through 9 should only ever have a 3 wire cable plugged in. Let us know about this then we can proceed.

#3

Yea I agree my team did this same thing when building test robots. You have to have Motor controls (mC29) to use motor ports 2-9.

#4

Switching to 1 & 10 worked perfectly thank you!. We did not receive any motor controllers with the kit tho.

#5

You should have two of these

http://www.vexrobotics.com/276-2193.html

#6

When my Daughter built the clawbot she used the 2 encoders (the were in a small box in the clawbot box) for the arm and the claw as these 2 motors were further away and especially for the claw needed their wires extending.

#7