# Control the rotation of a KEMAR motorized head from Matlab¶

The example below shows a simple position control of a motorized KEMAR head from MATLAB, using the matlab-genomix bridge (see Installation of the robotic tools). First, run the following commands on the computer connected to the motor controller:

$roscore &$ genomixd &
\$ kemar-ros


Then in Matlab, you can try the following commands to control the rotation of the head:

% Make sure that matlab-genomix installation directory is in your userpath
>> userpath('<prefix>/lib/matlab');

% Connect to genomix and load the kemar component
>> client = genomix.client('host-machine:8080');

% Execute the homing procedure
>> kemar.Homing();

% Set the reference velocity for position control to 50 deg/s
>> kemar.SetVelocity(50);

% Move the head to 45 deg with a blocking call
>> kemar.MoveAbsolutePosition(45);
% The prompt returns once the head has reached the position

% Move the head to -30 deg with a non-blocking call
>> r = kemar.MoveAbsolutePosition('-a', -30);
% The prompt returns immediately. While the head moves, r.status is 'sent'.
% When the goal is reached, r.status becomes 'done'.