1. A multi-degree-of-freedom stage control system comprising:
a multi-degree-of-freedom stage structured by a plurality of actuators;
an instruction generator for generating instructions of plural degrees of freedom;
a position arithmetic unit for calculating positions of plural degrees of freedom from signals of a plurality of sensors attached to a control object,
a control arithmetic unit for calculating operation amounts of plural degrees of freedom from the instructions of plural degrees of freedom and the positions of plural degrees of freedom;
a thrust force conversion arithmetic unit for calculating thrust force instructions of the plurality of actuators from the operation amounts of the plural degrees of freedom;
a current instruction unit for calculating current instructions which should be flowed to the plurality of actuators; and
a sensor configuration input device for selecting a desired sensor configuration from among a plurality of sensor configurations, wherein
the positions of plural degrees of freedom are calculated by using a position arithmetic expression corresponding to a selected sensor configuration.
2. The multi-degree-of-freedom stage control system according to claim 1, wherein the position arithmetic unit has position arithmetic expressions respectively corresponding to the plurality of sensor configurations in a memory in advance.
3. The multi-degree-of-freedom stage control system according to claim 1, wherein the position arithmetic unit has a function of adding position arithmetic expressions respectively corresponding to the plurality of sensor configurations later on as functions.
4. The multi-degree-of-freedom stage control system according to claim 1, wherein the sensor configuration input device has a sensor number input unit for inputting the number of sensor with respect to each of X axis, Y axis, and Z axis defined by a user.
5. The multi-degree-of-freedom stage control system according to claim 1, wherein
the sensor configuration input device is equipped with a sensor position input unit for inputting a position coordinate of each sensor used in the selected sensor configuration.
6. The multi-degree-of-freedom stage control system according to claim 1, wherein
the sensor configuration input device includes a sensor type input unit for inputting the type of each sensor used in the selected sensor configuration.
7. The multi-degree-of-freedom stage control system according to claim 6, wherein
the sensor type input unit is capable of selecting at least an absolute position sensor and a relative position sensor in which an activation position is zero.
8. The multi-degree-of-freedom stage control system according to claim 6, wherein
the position arithmetic unit includes a zero position signal detector for detecting a zero position signal of a relative position sensor, and has a function of storing a sensor signal that is obtained when the zero position signal is detected.
9. A multi-degree-of-freedom stage control system comprising:
a multi-degree-of-freedom stage structured by a plurality of actuators;
an instruction generator for generating instructions of plural degrees of freedom;
a position arithmetic unit for calculating positions of plural degrees of freedom from signals of a plurality of sensors attached to a control object,
a control arithmetic unit for calculating operation amounts of plural degrees of freedom from the instructions of plural degrees of freedom and the positions of plural degrees of freedom;
a thrust force conversion arithmetic unit for calculating thrust force instructions of the plurality of actuators from the operation amounts of the plural degrees of freedom;
a current instruction unit for calculating current instructions which should be flowed to the plurality of actuators; and
an actuator configuration input device for selecting a desired actuator configuration from among a plurality of actuator configurations, wherein
the thrust force instructions of the plurality of actuators are calculated by using a thrust force conversion arithmetic expression corresponding to a selected actuator configuration.
10. The multi-degree-of-freedom stage control system according to claim 9, wherein
the thrust force conversion arithmetic unit has thrust force conversion arithmetic expressions respectively corresponding to the plurality of actuator configurations in a memory in advance.
11. The multi-degree-of-freedom stage control system according to claim 9, wherein
the thrust force conversion arithmetic unit has a function of adding thrust force conversion arithmetic expressions respectively corresponding to the plurality of actuator configurations later on as functions.
12. The multi-degree-of-freedom stage control system according to claim 9 wherein,
the actuator configuration input device has an actuator number input unit for inputting the number of actuator with respect to each of X axis, Y axis, and Z axis defined by a user.
13. The multi-degree-of-freedom stage control system according to claim 9, wherein
the actuator configuration input device has an actuator position input unit for inputting a position coordinate of each actuator used in the selected actuator configuration.
14. The multi-degree-of-freedom stage control system according to claim 9, wherein
the actuator configuration input device has an actuator type input unit for inputting the type of each actuator used in the selected actuator configuration.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A pet bed, comprising:
a plurality of scissor bar sets, each of the scissor bar sets including two crossed bars pivotally connected where the two bars cross,
wherein upper ends of bars in adjacent scissor bar sets are pivotally connected and lower ends of bars in adjacent scissor bar sets are pivotally connected so that the plurality of scissor bar sets form a closed loop that defines a frame, the frame being foldable from a storage position in which the upper ends of the bars in the plurality of scissor bar sets are positioned adjacent to each other to an extended position in which the upper ends are spread apart and the upper ends are closer to the lower ends of the bars in the plurality of scissor bar sets than when the frame is in the storage position;
at least one structure on the frame configured and arranged to prevent the upper ends from moving to adjacent to the lower ends when the frame is in the extended state; and
a cover suspended from the upper ends.
2. The pet bed of claim 1, wherein the structure comprises a first stop positioned on one of the bars on a first of the scissor bar sets so that the crossed bars on the first scissor bar set are prevented from moving to a position where the upper ends of the crossed bars of the first scissor bar set are adjacent the lower ends of the first scissor bar set.
3. The pet bed of claim 2, wherein the structure comprises a second stop positioned on one of the bars on a second of the scissor bar sets so that the crossed bars on the second scissor bar set are prevented from moving to a position where the upper ends of the crossed bars of the second scissor bar set are adjacent the lower ends of the second scissor bar set.
4. The pet bed of claim 3, wherein the number of scissor bar sets in the plurality is exactly four.
5. The pet bed of claim 4, wherein the first and second scissor bar sets are on opposite sides of the frame.
6. The pet bed of claim 3, wherein the first and second stops each are spaced from where the respective crossed bars are pivotally connected.
7. The pet bed of claim 6, wherein each of the first and second stops comprises a groove for receiving the other of the bars of the respective first and second scissor bar sets.
8. The pet bed of claim 3, wherein each of the first and second stops comprises a groove for receiving the other of the bars of the respective first and second scissor bar sets.
9. The pet bed of claim 2, wherein the first stop is spaced from where the respective crossed bars are pivotally connected.
10. The pet bed of claim 9, wherein the first stop comprises a groove for receiving the other of the bars of the first scissor bar set.
11. The pet bed of claim 2, wherein the first stop comprises a groove for receiving the other of the bars of the first scissor bar set.
12. The pet bed of claim 1, wherein the upper ends of bars in adjacent scissor bar sets for the plurality of scissor bar sets are pivotally connected at upper pads.
13. The pet bed of claim 12, wherein the cover comprises pockets that extend over and around the upper pads.
14. The pet bed of claim 13, wherein the cover sags when suspended from the upper pads when the frame is in the extended position.
15. The pet bed of claim 14, wherein said at least one structure is independent of the connection of the cover to the upper pads.
16. The pet bed of claim 12, wherein the cover is suspended from the upper pads, and wherein said at least one structure is independent of the connection of the cover to the upper pads.
17. The pet bed of claim 12, wherein the lower ends of bars in adjacent scissor bar sets for the plurality of scissor bar sets are pivotally connected at lower pads.
18. The pet bed of claim 12, wherein the upper pads and lower pads are substantially similar.
19. The pet bed of claim 18, wherein the upper pads and lower pads comprise two pairs of flanges, with each pair of flanges having a pin extending between the pair of flanges, and wherein the bars connected to each pad are pivotally connected to the pins.
20. The pet bed of claim 1, wherein the cover is in the shape of a bone.