Programmable manipulator with dynamic feedback apparatus for stabilization

In a programmable manipulator, the combination

• of, a manipulator arm,
• means for moving said arm to different positions in a plurality of independent axes,
• memory storage means for storing digital representations corresponding to different positions of said arm in said axes,
• encoder means for each of said axes and operative to develop position signals corresponding to the actual position of said arm in said plurality of axes,
• comparing means for comparing command and position signals and developing an error signal related to the difference therebetween,
• means for sensing the velocity in at least one of said independent axes at a location on said manipulator arm than the location at which the encoder for said axis is positioned and for generating a dynamic feedback signal related to the acceleration in said axis, and
• means controlling said moving means for combining said error signal and said dynamic feedback signal.

In a programmable manipulator, the combination of,

• a manipulator arm,
• means for moving said arm to different positions in a plurality of independent axes,
• memory storage means for storing digital representations corresponding to different positions of said arm in said axes,
• encoder means for each of said axes and operative to develop position signals corresponding to the actual position of said arm in said plurality of axes,
• comparing means for comparing command and position signals and developing an error signal related to the difference therebetween,
• means for sensing the dynamic behavior of at least one axis of said independent axes at a location on said manipulator arm physically closer to the outer end of said manipulator arm than the location at which the encoder for said axis is positioned, and
• means responsive to said dynamic sensing means and said error signal for controlling said moving means.

In a programmable manipulator, the combination of, a manipulator arm,

• means for moving said arm to different positions in a plurality of independent axes,
• memory storage means for storing digital representations corresponding to different positions of said arm in said axes,
• encoder means for each of said axes and operative to develop position signals corresponding to the actual position of said arm in said plurality of axes,
• comparing means for comparing command and position signals and developing an error signal related to the difference therebetween,
• means for sensing the acceleration in at least one of said independent axes at a location on said manipulator arm closer to the outer end of said manipulator arm than the location at which the encoder for said axis measures positional data;
• function generator means responsive to said error signal;
• and
• multiplying digital to analog converter means having the output of said acceleration sensing means as a variable reference input and the output of said function generator means as a digital input, the analog output of said multiplying digital to analog converter providing a dynamic feedback signal which increases in magnitude with an increase in the output of said acceleration sensing means and increases with a decrease in said error signal.

In a programmable manipulator, the combination of, a manipulator arm,

• means for moving said arm to different positions in a plurality of independent axes,
• memory storage means for storing digital representations corresponding to different positions of said arm in said axes,
• encoder means for each of said axes and operative to develop position signals corresponding to the actual position of said arm in said plurality of axes,
• comparing means for comparing command and position signals and developing an error signal related to the difference therebetween,
• tachometer means for sensing the velocity in at least one of said independent axes at a location on said manipulator arm physically closer to the outer end of said manipulator arm than the location at which the encoder for said axis is positioned and providing an electrical velocity signal;
• means for differentiating said velocity signal to provide an acceleration signal proportional to the acceleration in said one axis;
• means for combining said acceleration signal and said error signal to provide a dynamic feedback signal which increases in magnitude with a decrease in said error signal and also increases in magnitude with an increase in said acceleration signal;
• and
• means for controlling said moving means in accordance with said dynamic feedback signal.

A control circuit for use with an apparatus which utilizes indirect position sensing to control the operation of said apparatus at a location physically remote from the point of position sensing, said control circuit comprising:

• means for developing an indirect position sensing signal;
• means including accelerometer means for sensing the dynamic behaviour of said apparatus at said remote location and providing an acceleration signal;
• means for generating a dynamic feedback signal related to the dynamic behaviour at said remote location and including function generator means responsive to said indirect position sensing signal and multiplying digital to analog converter means;
• said multiplying digital to analog converter means having said acceleration signal as a variable reference input and the output of said function generator means as a digital input and providing said dynamic feedback signal at the analog output thereof;
• and
• means for combining said dynamic feedback signal and said indirect position sensing signal to control the operation of said apparatus.