Question Group.docx

Question Group #1

1. How far off the centerline of the gantry Z-Axis is the 25 lbs.

payload?

Answer: From the center of our support stanchions the front mounting surface for payload is 443.8 mm (17.47 in). The anticipated payloads could extend from that point out approximately 457.2 mm (18 in).

2. How many cycles per hour for each gantry?

Answer: This will be based on the specification of the motors and motor controller specification. For current discussion assume 100% duty cycle unless we find out differently from suppliers of motors and controllers.

3. Is there a detailed Sequence of Operation available, including a timing chart?

Answer: Unsure as to what you may be looking for. No current sequence of operation has been designed.

4. What is the operating environment? Particularly the temperature range.

Answer: This product will be at nominal room temperature. Assume 21 Degrees C +/- 7 Degrees C

5. What is the purpose of the lower horizontal beam?

The lower horizontal beam may not be a design requirement but it is in the preliminary design to stabilize the payload particularly in the Z axis with the payload in high and low vertical position and also to stabilize to prevent twisting of the vertical beam.

6. The X-Axis repeatability is noted as +/- 25 microns.

(.000098”), which is about ¼ the thickness of a human hair. This would preclude the use of a traditional mechanical drive, such as a rack & pinion, belt, ballscrew, as any of these would have more backlash than 25 micron.

Also, if the temperature in the room varied by more than about ½ degree F, the repeatability would be gone. They also mention a “home” switch and we don’t think any commercial limit switch can react to the +/- 25 micron factor. Can you check on this repeatability requirement?

Answer: The intent of the gantry system is to very accurate and repeatable in position. I believe the gantry itself should be at least as accurate as the measuring system that may be used to verify the system. The X-axis drive spec lists +/- .1 mm repeatability, Y-axis drive spec lists +/- 1.3 micron bidirectional repeatability. We will try to achieve these numbers.

7. The horizontal travel speed is noted at 5 meters / sec. The horizontal travel distance for one gantry is 1610 mm. Allowing accel / decel time, this would put total travel for the 1610 mm at around .5 second.

Is this correct? If not, what is the allowable travel time for the 1610 mm distance.

Answer: Correct, we want to be able to move in the horizontal at the full 5 meters / sec. Remember also that although the horizontal beam is shown in 2 sections (for transporting and assembly) it is a continuous travel therefore with one system parked at extreme end the other can travel the combined total distance (almost 2x the 1610 mm) - the parking zone for the other vertical member. We have no current spec for braking time and distance from the 5 meter / sec speed at this time.

8. Will the outer test room walls be erected after the gantry is installed?

Answer: The assumption should be that the gantry will be installed after construction of the chamber. This will mean that the only entry point into the chamber will be through a 3' by 7' door.

9. Servo drives are called out as Parker Gemini, with the part number. Are part numbers also available for the servomotors?

Answer: I will have to investigate this further.

Question Group #2

1. Environment within enclosure. Temperature, Special Coatings on equipment?

Answer: This product will be at nominal room temperature. Assume 21 Degrees C +/- 7 Degrees C

2. Payload; Spec mentions 25 lbs. Is this including the EOAT, (End of Arm Tool)?

Answer: No

3. Is there a sequence of operation available?

Answer: Unsure as to what you may be looking for. No current sequence of operation has been designed.

4. Floor Thickness?

Answer: Will be specified at Design Kick-off review. For initial bid purposes, assume floor thickness will support conventional attachment methods.

5. Access to enclosure for Installation?

Answer: Assume that the only access will be through a 3' by 7' door opening.

6. Any equipment available for movement of beams into place? Ie; Fork Truck, Overhead Crane.

Answer: There will be no special equipment available for movement of beams.

7. Dynamics requested are velocity of 5 m/s. What is the acceleration?

Cycle time to complete full movement.

Answer: Cycle time will be based on the specification of the motors and motor controller specification. For current discussion assume 100% duty cycle. Acceleration specification will be based on the motor specifications.

8. Any controls specs other than details given for drives and motors?

Enclosure, HMI, ? Auto Mode, Manual Mode, Test?

Answer: All known specifications should be specified in PSD. Any additional details will be worked out at Design Kick-off review.

9. EOAT? Any prints? Will require some input for Z Axis carriage plate mounting.

Answer: End of arming tooling can be worked out at design kick-off review, and will not be complex. There are no prints available. All detailed questions concerning plate mounting can be addressed at design kick-off review.

10. Part presentation to the Gantries. How does this occur?

Answer: The gantry system is not complex enough to need to address this.

The part will remain on the gantry and will not move.

11. Safety Lock. Is this Güdel’s responsibility for enclosure?

Answer: There will be at a minimum an emergency shut-off switch -additional safety specifications will be specified at the design kick-off review.

12. Main Power? Assume 480 V, 3 Phase, 60 Hz.

Answer: Specified in PSD. Whatever is required by the system shall be made available.