Instrument carriage assembly for surgical system
A robotic assembly is configured to support, insert, retract, and actuate a surgical instrument mounted to the robotic assembly. The robotic assembly includes an instrument holder base member, a motor housing moveably mounted to the instrument holder base member, a carriage drive mechanism operable to translate the motor housing along the instrument holder base member, a plurality of drive motors, and a plurality of output drive couplings driven by the drive motors. One or more of the drive motors includes one or more magnetic flux shields to inhibit magnetic interference with an adjacent drive motor and/or with an adjacent motor orientation sensor.
1. A robotic assembly configured to support, insert, retract, and actuate a surgical instrument mounted to the robotic assembly, the robotic assembly comprising:
an instrument holder base member;
a motor housing moveably mounted to the instrument holder base member;
a carriage drive mechanism operable to selectively translate the motor housing relative to the instrument holder base member along an insertion axis of the surgical instrument;
a plurality of drive motors, each of the drive motors being mounted to the motor housing; and
a plurality of output drive couplings, each of the output drive couplings being drivingly coupled with a corresponding one of the drive motors, each of the output drive couplings being configured to drivingly couple with a corresponding input drive coupling of the surgical instrument;
wherein a first drive motor of the plurality of drive motors is elongated between a first end, and a second end, the first drive motor includes a first magnetic flux shield at the first end and a second magnetic flux shield at the second end, and the first magnetic flux shield is spatially separated from the second magnetic flux shield so that a portion of the first drive motor unshielded from magnetic flux exists between the first magnetic flux shield and the second magnetic flux shield.
2. The robotic assembly of claim 1 , wherein at least one of the plurality of drive motors includes a brushless component motor.
3. The robotic assembly of claim 2 , wherein at least one of the plurality of drive motors includes a brushless component motor having a trapezoidal-commutation motor constant greater than or equal to 1.25 oz.-in/sqrt(Watt).
4. The robotic assembly of claim 1 , wherein the magnetic flux shield includes a ring made of magnetically soft material containing at least one of iron, cobalt, or nickel.
5. The robotic assembly of claim 1 , wherein each of the plurality of drive motors includes two magnetic flux shields that are disposed at opposite ends of the drive motor.
6. The robotic assembly of claim 5 , wherein each of the magnetic flux shields comprises a ferrous ring.
7. The robotic assembly of claim 1 , wherein two drive motors of the plurality of drive motors are separated by less than 5 mm.
8. The robotic assembly of claim 7 , wherein two drive motors of the plurality of drive motors are separated by less than 2 mm.
9. The robotic assembly of claim 1 , wherein:
the plurality of drive motors includes five drive motors; and
each of the five drive motors is separated from at least two of the other drive motors of the plurality of drive motors by less than 5 mm.
10. The robotic assembly of claim 9 , wherein each of the five drive motors is separated from at least two of the other drive motors of the plurality of drive motors by less than 2 mm.