I want a flying / floating Charcter

Hello folks! I am currently working on a 2D sidescroller game for 2 players. Player 1 plays the jump 'n run part and has to walk from left to right. Player 2 controls a platform on which player 1 can jump so he doesn't fall. That's why player 2 needs to control the platform freely, like up, down, left, right (zero-gravity or something similar). I just can't figure out how to write the code for that. Currently it looks like this:

 var normalSpeed:float=6.0;
 private var speed:float=normalSpeed;
 var runSpeed:float=12.0;
 private var jumpSpeed:float=speed*1.7;
 var gravity:float=20.0;
 private var walkTime:int=0;
 private var moveDirection:Vector3=Vector3.zero;
 static var grounded:boolean=false;
 private var controller:CharacterController;
 private var flags:CollisionFlags;
 private var tr:int=90;
 function Start(){
     animation.wrapMode=WrapMode.Loop;
     animation["run"].layer=-1;
     animation["walk"].layer=-1;
     animation["idle"].layer=-1;
     animation.SyncLayer(-1);
     
     animation["jump"].layer=10;
     animation["jump"].wrapMode=WrapMode.Once;
     animation.SyncLayer(10);
     
     animation.Stop();
     animation.Play("idle");
     
     
     
 }
 
 function FixedUpdate(){
     if(grounded){
         moveDirection=new Vector3(Input.GetAxis("HorizontalP1"),0,0); //new
         //moveDirection = transform.TransformDirection(moveDirection); //new
         moveDirection*=speed; 
         if(Input.GetButton("JumpP1")){
             moveDirection.y=jumpSpeed;
             animation.CrossFade("jump");
         }
         
     }else{
         moveDirection=new Vector3(Input.GetAxis("HorizontalP1"),moveDirection.y/speed,0);
         moveDirection*=speed;
         
          if (Input.GetButton ("Jump")) {  //new
         moveDirection.y = jumpSpeed;    //new
     }    }
     
     moveDirection.y-=gravity*Time.deltaTime;
     controller=GetComponent(CharacterController);
     flags=controller.Move(moveDirection*Time.deltaTime);
     
     grounded=(flags & CollisionFlags.CollidedBelow) !=0;
     if(flags && CollisionFlags.CollidedBelow){
         grounded=true;
         }else{
         grounded=false;
         }
     
     //if(moveDirection.x>0){
     //tr=90;
     //}else if(moveDirection.x<0){
     //tr=270;
     //}
     
     //transform.eulerAngles.y-=(transform.eulerAngles.y-tr)/5;
     //tr is the target rotation
     //var currentRotation=transform.eulerAngles.y;
     //var rotationDifference=currentRotation-tr;
     //var amountToRotate=rotationDifference/5;
     //transform.eulerAngles.y -= amountToRotate;
     
     
     
     if(Input.GetAxis("HorizontalP1")>.2 || Input.GetAxis("HorizontalP1")<-.2){
         if(walkTime>40){
             animation.CrossFade("run");
             speed=runSpeed;
             }else{
             walkTime++;
             animation.CrossFade("walk");
             speed=normalSpeed;
             }
             jumpSpeed=speed*1.7;
             
             }else{
             walkTime=0;
             animation.CrossFade("idle");
             }
             
 }
 
 
 @script RequireComponent(CharacterController)

I hope you can help me! greetings, T.