scr or servo 116 which is coupled to and receives input from the processor 100 similarly the cooling fan 114 is controlled by controller 118 which is coupled to and receive input from the processor 100 as mentioned above a hand held controller 54 is coupled to the processor 100 by a cable 52 the hand held controller includes several switches and indicator lights which aid the user in the operation of the invention according to a presently preferred embodiment of the invention the hand held controller 54 includes a pump on off push button 120 and a pump on indicator light 122 push buttons 124 and 126 are provided for respectively increasing and decreasing water pressure a rocker switch or thumb joy stick 128 is provided for changing the direction of movement of the cross member 28 in fig1 and 4 push buttons 132 and 134 are provided for respectively increasing and decreasing the speed of movement of the cross member a memory push button 136 is also provided and a memory indicator light 138 is provided to signal when the memory function is activated the memory function is described in more detail below with reference to fig6 an auxiliary indicator light 130 is provided.