Computer vision robot arm using homography calibration

Hi, Im doing a project on Robot arm object detection and grasping.
im using Homograohy method to calibrate the camera from four corner image points and real world measurement of it. real world coordinate now.example x=10,y=0,z=12. z is actually the depth from robot arm base to target point which remains same for everything.
robot arm i have is Articulate robot (waist,shoulder,elbow).
i Dont know how to make the robot arm end effector to move towards the target point.
I’m new to this so i tried many ways by even adding reference point as well but its complete failure.
it would be thankfull if anyone helps me in this.
thanks in advance

i tried to add a refernce point by recording joint angles and the end effector position in real world coordinate.I have tried some Inverse kinematics and still its wrong.
i feel there is some basic issues like the work place is front facing for the camera and robot arm so there might be some axis mistake or robot arm calibration since its custom made which world with arduino.
i dont understand where im lost but the goal is to make robot arm move towards the target real world point

details please. what learning/research have you done on the topic?

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