A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | AA | |
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1 | RIX = Review Item X, where X could be C, D or Q, i.e. an RIC would be a Comment on a particular item, an RID would note a Discrepancy, and an RIQ a Question. | ||||||||||||||||||||||||||
2 | RIX Nr. | Reviewer | Type (RIC/RID/RIQ) | Document No. | Section | Page | RIX Text | Reply By | RIX Reply | Action Number | Action | Action Status | Closed By | Closure Reference | |||||||||||||
3 | 1 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 13 | The design drivers (operating range, clear aperture) appear to be taken from the Preliminary Design and Analysis Report, rather than the FPRD. Surely, the design should be driven by the actual requirements, rather than the performance achieved by the preliminary design? | AOA | - We agree that the design document should not be the source of the requirements to be included in the Compliance Matrix, however, there are some requirements that are not covered by the FPRD, section 8 and 9. So, we decided alos to use this document as requirement source. - All the requirements are clasified by document and by section. Howerver, the requirement ID has been defined as an arbitary and subsecuent number, as only requirements of FPRD document, section 8 & 9 include the identification number. | The requirements referred to the Preliminary Design and Analysis Report eliminated from the Design Drivers. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
4 | 2 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 14 | The requirement in the FPRD is 480 degrees with a goal of 540 degrees. | AOA | It will be corrected on the Desig and Analysis report. Even though, the design has been develped to maximize this rotation range (see answer to Rix 3) | Corrected the rotation range requirement to be compliance to the requirement specified in the FPRD. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
5 | 3 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 14 | The 8 degree safety margin is not compliant with the requirements of the FPRD which states that: 1. The limit switches are installed at positions corresponding to a movement of 5 degrees beyond the nominal operating range; 2. The end stops/dampers are installed at positions corresponding to a movement of 3 degrees beyond the electrical limit switches. Their stroke corresponds to a rotation angle of 4 degrees; 3. The cable wrap shall be able to move without damage 7 degrees beyond the position where the dampers are fully compressed. | AOA | The maximum rotation angel achievable with the developed rotator solution and the rotator volume constrains is of ±249°, so it has been concluded that the requirement of the FPRD (±15° additional range for limit switches, end stops and safety margin) is not achievable without reducing the rotation range below the minimum required. Hence, the following distribution has been proposed: 1. The limit switches are installed at positions corresponding to a movement of 1 degree beyond the nominal operating range 2. The end stops/dampers are installed at positions corresponding to a movement of 3 degrees beyond the electrical limit switches This way, the cable wrap is able to move without damage 1.65° degrees beyond the position where the dampers are fully compressed. This safety margin could be incremented locating the dampers nearer to the limit switches, so both components will be working at the same time and the rotator will be stopped earlier, leaving a greater angular distance to the end of rotation of the Cable Chain. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
6 | 4 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 14 | A major drawback of the presented solution is that access to the connector box is more difficult, due to the presence of the cable wrap of the adjacent FC-rotator. | AOA | It is agreed that the developed solution reduces the accessibility to the connector box, but this solution has been selected to avoid the necessity of including additional parking switches, and it is ensured that sufficient accessibility is provided to the connectors panel. | Enlarge the connectors panel outputs to both sizes to ensure a better access. | Pending Action for IDOM | |||||||||||||||
7 | 5 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 15 | There appears to be very little clearance between the connector box and the swept volume of the adjacent FC-rotator's cable wrap. I strongly advise that a minimum of 25 mm clearance should be observed to accommodate e.g. flexure, manufacturing and installation tolerances, etc. | AOA | The spaces have been optimized. With the developed design, the clearance between the connector box and the FC-rotator's cable wrap cannot be increased. | Enlarge the connectors panel outputs to both sizes to ensure a better access. | Pending Action for IDOM | |||||||||||||||
8 | 1 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 15 | The actual envelope of drawing DR/GTC/004 is model-based and should be confirmed by measurments on site. | DFO | Ok, we would appreciate this on site measures, to confirm that there is no collision between FC Set rotator and Hipercam. | Provide on site measurements of the envelopes | Pending Action for Sheffield/Durham | |||||||||||||||
9 | 2 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 15 | The main rollers of the cable rotator stay outside the envelope of FC-F when end stop dampers are completly compressed? | DFO | Yes, the main rollers are out of the FC-F envelope (see attachd image). | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
10 | 6 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 16 | Do we rely on gravity to ensure that the in-plane positioning screws "engage" with the telescope structure during alignment? | AOA | Yes, the gravity will help to the vertical alignment. | Pending For Revision of Sheffield/Durham/GTC | ||||||||||||||||
11 | 3 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 16 | The area of the telescope structure, where the lateral pushing screws ara touching, is not so well defined as in the 3D-model. The exact available space should be checked on site. | DFO | We would appreciate to receive the information of the exact space between the telescope structure and the rotator part. | Provide on site measurements of the exact space between the telescope structure and the rotator part | Pending Action for Sheffield/Durham | |||||||||||||||
12 | 7 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 17 | Two options for tilt adjustment are provided ("push" screws and shims); which one is preferred? | AOA | The push screws will be used to adjust the tilt of the rotator and the shims will be used to fill the gap left. | Description of this design updated on the Mechanical Design and Analysis Report to clarify this fact. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
13 | 8 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 17 | What is the nominal separation between the telescope interface flange and the rotator housing (to accommodate the adjustment screws or shims); this affects the location of the instrument interface flange and thus the back-focal distance. | AOA | There is no a nominal rotator position. The gap between rotator and telescope flanges will depend on the tip/tilt alignment. If the back-focal distance shall be optimized, the shims of the interface could be removed where they are not required. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
14 | 4 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 17 | Alignment shims should be washers to avoid falling out of the gap during alignment. The excess of work for placing them is acceptable. Only a few pushing screws are necessary for opening the gap. | DFO | Ok, we will change the designs of the shims to a washers shims. For opening a gap the M16 screws could be used. | Shims changed to washer shims by IDOM. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
15 | 9 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.2 | 18 | The interface with HiPERCAM is still TBC. | AOA | A interface with HiPERCAM has been proposed by IDOM in the design, which will have to be confirmed by Sheffield/Durham. | Confirm the interface with HiPERCAM | Pending Action for Sheffield/Durham | |||||||||||||||
16 | 5 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 24 | Chemical niquel plating is recommended for protecting the motor housing from cooling water. | DFO | Ok, a chemical niquel plating or similar treatment will be made to protect the housing of the motor | Treat the Main Static Housing with a chemical niquel plating or similar to protect it from cooling water. | Pending Action for IDOM | |||||||||||||||
17 | 10 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 25 | I am not convinced that the Field of View Cover is fit for purpose. Looking at figure 4.19, the instrument is located on the left and there appears to be a direct path from the (optical) encoders into the instrument. In addition, the cover prevents access to the encoder heads and tape for maintenance. | AOA | The cover's porpose is to avoid any bright surface on the elements (such as the encoder tape) that could affect to the field of view. Even if the encoder is optical, it does not emit any light, so it will not affect the field of view. For the encoder heads maintenance operations, this cover will be removed. | Description of this design updated on the Mechanical Design and Analysis Report to clarify this fact. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
18 | 6 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 25 | FOV-Cover. Reduce outer diameter for bigger dimensional margin to telescope I/F-flange. | DFO | Ok, we will reduce the outer diameter of the cover | Outer diameter of the FOV Cover reduced by IDOM for bigger dimensional margin to the telescope I/F Flange. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
19 | 7 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 26 | The connector panel support could provide more space without the middle strut. | DFO | We will remove de middle strut to provide more space for the cable route. | Remove the middle strut of the Connector Pannel Support to provide more space. | Pending Action for IDOM | |||||||||||||||
20 | 11 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 28 | How frequently does the bearing have to be re-greased and how long does this operation take? Has this been included in the calculation of the Mean Preventive Maintenance Time? Does this have to be done from inside the telescope elevation ring, or can it be done from the outside? Is there any risk of the grease/oil contaminating other areas (e.g. grease migrating onto the encoder tape)? | AOA | This information will be defined in the Maintenance Manual document. | Include the information regarding the maintenance of the bearing in the Maintenance Manual document. | Pending Action for IDOM | |||||||||||||||
21 | 8 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 28 | The bearing should have a tight seal to the motor side avoiding grease overflow into the motor. | DFO | We will ask to the main bearing supplier to install an apropiate seal to avoid any grease leackage on the motor side. | Ask the main bearing supplier to install an appropiate seal to avoid any grease leackage on the motor side. | Pending Action for IDOM | |||||||||||||||
22 | 8b | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 28 | What was the reason for discarding VEUS? | ASA | The ETEL motor is the motor that better fits with the design, torque & consumption requirements | - | CLOSED | ASA | ||||||||||||||
23 | 9 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 28 | The rotor of the motor needs a tangential definition for mounting. | DFO | The installation of the rotor in the stator will be guided by the main structures that compound the rotator. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
24 | 10 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 29 | Water cooling connections of the motor should be on the bottom of the rotator. | DFO | We will install the watter coling conector on the bottom of the rotator | Install the water cooling connections of the motor on the bottom of the rotator. | Pending Action for IDOM | |||||||||||||||
25 | 11 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 29 | There is no space for the cables of the motor (24 mm to next rotating part for a right-angled deviation of a 17,5 mm cable). | DFO | The correct exit connector for the power supply of the motor is not well represented in the 3D-Model neither in the document. We will correct this. The correct exit connector for the motor is as shown in the picture. It is a rigth angle conector with maximun heigh of 38,6 mm wich is far from the next rotating part (56,15 mm). | Correct the exit connector for power supply of the motor on the 3D Model and the Mechanical Design and Analysis Report. | Pending Action for IDOM | |||||||||||||||
26 | 12 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 31 | Is the switching between primary and redundant encoders achieved electronically, or do they need to be changed over manually? | AOA | The switching between primary and redundant encoders will have to be done manually. The three encoders will be connected to the connection pannel and the cable comming from the Drive can be switched between the encoders. | Update he desciption of this design on the Mechanical Design and Analysis Report to clear this fact. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
27 | 13 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 31 | Could all three encoders be utilised simultaneously to increase accuracy? | AOA | The three encoders cannot be used simultaneoulsly, since an additional device is required to get the average of two signals. At any case, the accuracy obtained using one encoder is better than the requested in the requirements. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
28 | 14 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 31 | Do the encoder tape and heads require maintenance, e.g. cleaning? How frequently does this need to happen and how long does this operation take? Has this been included in the calculation of the Mean Preventive Maintenance Time? | AOA | This information will be defined in the Maintenance Manual document. The encoder tape shall be cleaned with a non-dust cloth when a signal of failure is detected. | Include the information regarding the maintenance of the encoder tape and heads in the Maintenance Manual document. | Pending Action for IDOM | |||||||||||||||
29 | 15 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 31 | As the encoders provide absolute positioning information, could they be used as a substitute "parking switch" to enable implementation of the "active solution" option on page 14 and thus facilitate access to the connector box (see also RIX 4)? | AOA | The encoder only gives abosolute position when the homing sequence is performed. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
30 | 16 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 33 | Are the limit switches normally closed? | AOA | Yes. | - | CLOSED | AOA | ||||||||||||||
31 | 17 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 34 | The margins appear small (see also RIX 3). | AOA | See answer to RIX 3. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
32 | 18 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 35 | Maybe I'm missing something, but why is the limit switch not activated during step 1? | AOA | At step 1, the system achieves the first Limit Assembly, at a rotation of ±118°, where the system must not be damped, so the brakes will not be activated, and dampers will not stop the rotator at this point. At this rotation point, the limit switch will give a signal to get information about the rotation direction, which will be used, together with the information given by the reference switch, to stop the rotator if it reaches the other Limit Assembly, at a rotation of ±241° | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
33 | 19 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 35 | I don't understand the function and operation of the Toggle Pin Detectors (maybe I'm confused by their name)? See also RIX 18. | AOA | The Toggle Pin Detectors have been introduced to ensure the Limit Switches are activated during the whole time in which the dampers are working, as a safety margin to avoid the Limit Switches being deactivated when the dampers start to work and so the brakes would also be deactivated. Hence, these elements will activate the Limit Switches at a rotation of ±241° and they have been dimensioned to ensure the Limit Switches will remain activated until the damper is fully compressed | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
34 | 12 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 35 | The manufacturer of the damper indicates maximum angles for force incidence which are probably not respected. Changing the orientation of the damper could split this angle in plus/minus. | DFO | The position of the damper has been modified to avoid side forces higher than 15 degrees | Modify the position of the damper to avoid side forces higher that 15 degrees. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
35 | 13 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 35 | Acording to manufacturers indications, the piston of the damper should not act as mechanical limit, but the housing of the damper can mount a special sleeve for this purpose. | DFO | The steel cap of the damper is going to act as a mechanical limit | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
36 | 14 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 35 | Limit base plate should be pined to transfer forces to the motor lid. | DFO | Ok, some pins will be integrated. | Integrate some pins on the Limit base plate. | Pending Action for IDOM | |||||||||||||||
37 | 20 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 36 | Is the reference switch operated by the "Toggle Pin" rather than the "Toggle Pin Detectors"? | AOA | Yes, the reference switch is operated by the Toggle Pin. | - | CLOSED | AOA | ||||||||||||||
38 | 21 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 37 | OK, I may be getting it; whether or not the limit switch is "activated" depends on the status of the reference switch? This is not a fail-safe architecture, but I suppose it is only a safety feature backed up by another safety feature (i.e. the hard stop)... | AOA | Yes, the reference switch will be used to know wether each of the limit switches shall be activated, depending on the direction of the rotation of the sytem and the reached positions | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
39 | 15 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.2 | 38 | It's not clear how the brakes can be dismounted (access to the screw in the middle). | DFO | The base of the brakes will be modified to loose and tight the middle bolt. | The base of the brakes modificated by IDOM to loose and tight the middle bolt | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
40 | 16 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 40 | The rotor of the motor is clamped between the "Main Rotating Hub" and the "Rotating Motor Support". It is suposed the torque is handled by friction. If this is so, a gap must be forseen between both parts, but this gap excludes conventional bolted joint calculations. The rotor should be fixed in another way. | DFO | The joint will be redesigned to transmit the loads through the structures and not through the motor. The rotor of the motor will be fixed by bolts to the rotating structure. | Redesign the clamping of the rotor of the motor to transmit the loads through the structures and not through the motor. The rotor of the motor will be fixed by bolts to the rotating structure. | Pending Action for IDOM | |||||||||||||||
41 | 22 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 41 | What is the material of the "Sail Skirting Fringe"? Is this item subject to wear and could it be a source of swarf or debris? | AOA | Composite. Some wear could appear on the Sail Skirting Fringe, but no debris is foreseen. This is the same element that was installed in the CG-Set. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
42 | 23 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 42 | The text relating to the Cable Chain End Support seems to contradict itself? | AOA | Yes, there is a mistake. The Cable Chain End Support is bolted to the static part of the cable chain. It will be corrected on the Design and Analysis Report. | Mistake corrected on the Mechanical Design and Analysis Report | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
43 | 24 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 43 | Cables should NEVER be twisted. However, there is a fundamental difference between braiding and twisting, and braiding the cables will avoid the issues (i.e. differential bending) you have identified. As far as I am aware there is no objection to optical fibres being part of a braided cable harness; Durham have successfully built braided fibre harnesses containing thousands of fibres (e.g. Subaru FMOS). Another option would be to braid cables around the fibre, so that the fibre would be at the centreline of the cable braid. | AOA | It is a grammatical mistake. Twisted word will be replace by braiding. | Mistake corrected on the Mechanical Design and Analysis Report | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
44 | 25 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 43 | It is excellent that the cable chain can be easily detached to facilitate cable replacement! How long do you estimate it would take to detach and re-install the cable chain? Are any special tools required and will these be provided? Is the tension in the Ring Locking Tensor critical for the smooth operation of the cable wrap, and how is this tension controlled? I trust that a procedure for this operation will be documented in a maintenance manual which will be delivered with the hardware. | AOA | The cable chain replacing time will be estimated during the assembly process. The preloading of the ring locking tensor will be defined during the assembly stage. | Estimation of the cable chain replacing time and the preload required on the ring locking tensor during the assembly stage. | Pending Action for IDOM | |||||||||||||||
45 | 26 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 45 | I am not convinced that 10 Small Guiding Rollers are sufficient. I suspect that the cable chain will "straighten" out between two rollers causing it rub against the Intermediate Guiding Structure, which will increase friction and cause wear to the IGUS cable chain. | AOA | Intermediate rollers will be included. | Intermediate Small Guiding Rollers included on the Cable Chain. The initial amount of 10 Small Guiding Rollers has been increased to 21. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
46 | 27 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 45 | It is not clear to me how the design ensures that a minimum bending radius of 80mm is achieved. It should also be borne in mind that the bending radius is defined as the radius of the cylindrical surface around which the cable is bent, NOT at the centreline of the cable (see figure). If braided cables are used, the bending radius may be assumed to be equal to the bending radius of the centreline of the braid. | AOA | A bending raudius of 85mm is given by the big rollers. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
47 | |||||||||||||||||||||||||||
48 | 28 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 45 | How are the cables managed between the connector panels (on the connector box) and the entrance to the cable chain? Are the minimum bend radii of the conduits respected? Space looks quite tight in this area! Likewise at the output end of the cable chain. | AOA | The minimum bending radius is respected leaving an extra length of the cables. The allowable space is optimazed to its maximum extension. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
49 | 29 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 45 | You mention steel wheels; do you mean bronze? | AOA | Yes, it is a mistake. It should say bronze rollers. It will be corrected on the Design and Analysis report. | Mistake corrected on the Mechanical Design and Analysis Report | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
50 | 17 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 47 | The fixed ends of the cable chains need adjustment possibility in tangential direction to control the tensión of the chains, idealy a bit more than half cable chain link length. | DFO | Big rollers are fixed together with a rod that allow us to adjust the tension between two cable chains, preloading the threaded rod. Also the ends of the fixed part of the cable chains have some milimeters of adjustment. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
51 | 30 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 52 | I cannot find cable #4 in the diagram; is there a labelling error in the figure? | DFO | Yes, a labelling error has been detected. | Correct the labelling error on the diagram of the Cable Chain Assembly interna cable layout. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
52 | 31 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 52 | You appear to contradict what you said earlier; see also RIX 24. | DFO | See answer to RIX 24. | Mistake corrected on the Mechanical Design and Analysis Report | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
53 | 18 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 52 | Cable braids must be represented with their envelope (circle around the cable braid). So the real required space is shown. | DFO | We will redistribute the cables and represent the braids inside the cable chains, in order to show a more real situation. | Represent the envelope required by the cable braids. | Pending Action for IDOM | |||||||||||||||
54 | 19 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 52 | Normally the clamping elements on the end of the cable chain need a lot of space making quite dificult or impossible to fix all that cables in a right manner. | DFO | We have forseen an IGUS sistem that allow us to fix all the cables easily and organized. The way is to fix the cables with ties in special parts provided by IGUS as show in the images. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
55 | 32 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.4 | 53 | The connectors for coolant inlet and outlet and dry air are different from those specified in the FPRD. | DFO | A proposal has been done following the recommendations from Staubli. As introduced on an email from A. Ormaetxe on 17/06/2021, the following proposal has been done: 1. For cables 28 and 14, Staubli CBI09-7102 connectors are defined, but after talking with the supplier, we found out that this option does not include a panel mounted solution, so the SPT type Staubli connectors are proposed. 2. For cable 26, a KUHNKE-50.064 connector is proposed. It is proposed to use also a connector form Staubli introducing a possible solution with the RCS08.2102 from Staubli. This is just a proposal made by IDOM, still TBD. | Definition of the connectors to be included for Generic Telescope Services. | Pending Action for Sheffield/Durham | |||||||||||||||
56 | 33 | Marc Dubbeldam | RID | 101815-GTC-HCAM-00-000 | CAD Model | The connector panels shown in the CAD model only accommodate 28 conduits; 29 are required. | DFO | Following the response to RIX 30, a labelling error has been detected.This mistake will be corrected. | Correct the labelling error on the diagram of the Cable Chain Assembly interna cable layout. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||||
57 | 34 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.4 | 53 | So the connection between the control electronics and the rotator's internal wiring is made at the connector box? These connectors appear to be missing from the CAD model. | ASA | All the connectors are already defined but the connection box is still to be integrated. It will be integrated before the manufacturing phase. | Integrate the connection box. | Pending Action for IDOM | |||||||||||||||
58 | 20 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.3 | 53 | Why the coolant connectors are of that huge size? | ASA | From the Table 1 on the FPRD, a cable outside diameter <32mm is indicated for the coolant inlet and outlet, so a connector of nominal diameter of 25mm, which is of a big size. If a so elevated diameter is not required, a smaller connector could be selected. | Definition of the required diameter for coolant inlet and outlet. | Pending Action for Sheffield/Durham | |||||||||||||||
59 | 35 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.5 | This is not my field of expertise; GTC to review and approve. | ASA | Ok. | - | Pending For Revision of Sheffield/Durham/GTC | ||||||||||||||||
60 | 21 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.5 | 59 | Second hall sensor spare set is not shown. | ASA | To be included in the hardware arquitecture. | Hall sensor spare set included in the arquitecture. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
61 | 36 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.6 | 62 | What's the actual colour of RAL 7016 and RAL 7047? | ASA | RAL 7016 - RAL 7047 | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
62 | 22 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.7 | 62 | A transversal bar should be provided with the test bench, keeping low the overall lifting height without interference between dummy and lifting elements. | ASA | A commercial lifting tool like the attacheed picture will be used to manipulate the rotator with the test bench. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
63 | 37 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.8 | 64 | The design of the lifting device appears to be incompatible with the location of the lifting point as shown in Figure 4-76. | ASA | The description of the lifting device will be updated to clarify the adjustment of the fixture to the rotator. | Update the description of the lifting device on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
64 | 38 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.8 | 64 | Section 4.5.4 states that the rotating structure is assembled using M6 screws throughout; Figure 4-76 then suggests that during a lifting operation the entire weight of the rotator (> 400 kg) is supported by 6 M6 screws only? That makes me nervous and I would like to see an analysis to assure me that this is OK. | ASA | Each M6 bolt can resist 400kg (with a safety factor of 4). Nevertheless, a brief calculations will be included in this section. | Include a brief calculation to verify the lifting of the rotator with 6 M6 bolts. | Pending Action for IDOM | |||||||||||||||
65 | 39 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.8 | 64 | It is difficult to judge from the figures, but I suspect that the lifting device will collide with the adjacent rotator during installation. In addition I suspect that there is insufficient clearance around the rotator itself (particularly the connector box) to allow safe installation. See also RIX 4 and 5. | ASA | There is a small colission with the envelope of the big rollers of the FC-Set chain, but the lifting of the HiPERCAM rotator will not be carried out while the FC-Set's roller are at that position, so no collision is expected. See answer to RIX 4 and 5. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
66 | 23 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 4.5.8 | 65 | Is the lifting tool compatible with the c.o.g. of the rotator? | DFO | Yes, the lifting tool is compatible with the c.o.g. of the rotator as could be seen in the attached image. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
67 | 40 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.1 | 70 | Strictly speaking, a gravity load in the z-direction will produce out-of plane bending moments as the instrument CofG is located ~50 mm off-axis. However, I agree that these loads can be ignored. | AOA | An analysis with the loads in z-direction was also performed to check the magnitud of the introduced deformation where small. | - | CLOSED | AOA | ||||||||||||||
68 | 41 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.1 | 70 | Have the loads induced by telescope movements (accelerations/rotations) been considered? | AOA | No. The load cases considered are the ones indicated on the requirements. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
69 | 42 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.1 | 72 | The inertia of the instrument (Ixx and Iyy) has been ignored; how does this affect the accuracy of the modal analysis? | AOA | This information was not provided on the functional requirements documentation, so it has not been considered on the calculations. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
70 | 43 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.1 | 73 | The figures in Table 5-7 are not consistent, for example the error on the mass of the cable chain support upper is 3.4 kg, which is ~30%! | AOA | An update of the components masses due to design modification was performed, but the Error colum was not updated. A Total Error of 0.78% is obtained after the design update, showing a small deviation between the FEM model and the CAD model. This will be corrected on the document. | Correct the figures in Table 5-7 of the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
71 | 24 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.1 | 73 | The bearing is not listed in table 5-7. | DFO | It will included on the Table 5-7. | Include the bearing on the Table 5-7. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
72 | 44 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.1 | 76 | So, bolted connections are modelled by coupling the DoFs of selected nodes on mating surfaces; only nodes within the footprint of the bolt head are coupled rather than the entire surface. Is that correct? Or is each bolt modelled using a single pair of nodes? | AOA | Correct, the bolted connections have been modelled by coupling the DoFs of the mating surfaces. From the loads obtained on the joint, the theoretical bolt of the joint that will be loaded with the maximum traction axial load and transverse load is checked | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
73 | 25 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.2 | 78 | The bearing manufacturer normally indicates the bearing stiffness assuming an infinte high stiffness of the adyacent structure. Consequently, the surface where the remote moment is applied should not show deviations from a plane. However, this will not have significant influence on the global results. | DFO | Ok. | - | CLOSED | AOA | ||||||||||||||
74 | 45 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.3 | 79 | I'm not sure whether it was mentioned explicitly elsewhere, but the modal analysis was performed with a dummy mass of 650 kg to represent the instrument? | AOA | Yes, a dummy mass of 650kg at a distance of 1m to the Instrument I/F flange has been introduced to represet the Instrument (page 72 of the Design and Analysis Report) | - | CLOSED | AOA | ||||||||||||||
75 | 26 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.4 | 83 | Force application and result readout are not really clear. How is the remote mass applied? (flexible?) How are the results are extracted? | DFO | Further explanations will be included in the document to make these processes clear. | Include detailed explanations in the performed FEM Analysis description. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
76 | 46 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.5 | 85 | The FPRD states that the instrument shall survive the specified seismic loads; the performance requirements need not be met under these conditions and consequently only the deflections calculated in section 5.2.4 (i.e. for the nominal operating conditions) should be considered in the alignment budget. | AOA | It was understood from the Performance Requirement 10 and 11 on Page 14 of the FPRD, that, since the performance requirements shall be met under all operational, environmental and loading conditions, the earthquake loads were included. The alignment budget will be updated to include only the deflection under gravity loads. | Update the alignment budget to include only the deflection under gravity loads. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
77 | 27 | Benjamin Siegel | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.6 | 85 | The second accident scenario is not really realistic since the drive only supplies 24 A peak. | DFO | This second accident scenario will be removed. | Remove the second accident scenario of the Mechanical Limits Failure Mode Analysis on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
78 | 47 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.6 | 86 | I am not convinced that the calculations in this section (and therefore those of section 5.4.5) are correct, as you ignore the geometry of the Limits Actuator (Toggle); the force of the Toggle Pin is applied at a radial distance of 32.5 mm from the Kin Pin, whereas the force of the damper is applied at a radial distance of 46 mm. This effectively reduces the unbalance torque transmitted into the damper and consequently the work done, as the stroke has not changed. | AOA | A conservative scenario has been considered. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
79 | 48 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.6 | 87 | I cannot reproduce the figures for the unbalance energy reported in Table 5-14 using the assumptions and equations in this section. Are the reported figures correct? | AOA | The figures of Table 5-14 will be reviewed. | Review the figures of Table 5-14. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
80 | 49 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.6 | 87 | I am worried that the geometry of the Limits Actuator (Toggle) could transmit non-axial (bending) loads onto the damper piston and thus bend the piston and damage the damper. | AOA | See Rix 12. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
81 | 50 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.6 | 88 | Isn't the maximum shear stress in a circular beam 4/3 x the average shear stress? | AOA | We are not used to make this assumption. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
82 | 51 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.2.6 | 89 | Would the worst-case shear not occur at the neck of the threaded section, which (for an M8 thread) has a diameter < 6.5 mm? What about the bending moment in that area? I'm not convinced that the Toggle Pin will survive. | AOA | The Toggle Pin is fitted at its widest diameter section, so that the shear is applied in this area of the pin and not in the smallest section area. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
83 | 28 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.1 | 90 | In modelling class I of guideline VDI 2230, part 2, adyacent parts are glued in limited areas defined by limiting value G'. In the FE model, adayent parts seem to be glued on the whole contact surface. So, how are the reaction forces for the screws are obtained? | AOA | The bolted connections have been modelled by coupling the DoFs of the mating surfaces. From the loads obtained on the joint, the loads on each bolt are obtained by an equilibrium of the forces. The theoretical bolt of the joint that will be loaded with the maximum traction axial load and transverse load is checked | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
84 | 29 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.1 | 90 | Mixing maximum values for axial forces and shear forces of diferent screws leads to a distorted impression of safety factors. | AOA | Even the result of the safety factor is not the most realistic one, it is obtained with the most conservative assumption, so we consider that this value is acceptable for the verfication of the botls to be installed in the rotator. | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
85 | 52 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.1 | 94 | The screw sizes listed in Table 5-16 appear to be non-standard? Are M6x48.6 screws available? | AOA | This is the lenght used for bolt verification, but the lenght will be adapted to a standard dimension. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
86 | 53 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 95 | Is the "necessary preload" the actual preload to which the screw will be tightened? | AOA | No, this is the minimum preload required to ensure there is not bolt opening. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
87 | 54 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 95 | Are the bolt stress margin, thread resistance margin and surface pressure margin calculated for the maximum admissible preload or for the actual preload? | AOA | The bolt stress margin is calculated from the maximum admissible preload and comparing it with the bolt yield stress. The thread resistance margin has been obtained calculating the minimum length of engagement required, with the formula shown in page 93, which, compared to the real length of engagement, allows to analyse whether the bolt external thread will resist. The surface pressure is obtained comparing the actual surface pressure with the maximum allowable surface pressure, using the expressions from page 92. The maximum allowable surface pressure is obtained with the maximum admissible preload, while the actual surface pressure is calculated combining the actual preload with the axial load on the bolt. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
88 | 55 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 95 | The safety margins appear a bit small; would it help if larger screws were selected (i.e. M8)? | AOA | The joints in which the safety factor is close to one, the length of the thread will be increased up to two times the metric of the bolt. | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
89 | 56 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 95 | The analysis seems to suggest that the correct preload is essential; how will the correct pre-load be achieved during assembly? | ASA | The preload of the bolts will be taken from thr VDI 2230 part 1 standard. This preload will be given by calibrated torque wrenches. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
90 | 30 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 90 | How were the bolt loads determined? | ASA | Loads and moment values in the joint plane are obtained from the FEM Analysis. Then, this loads are transmitted to each bolt by an equilibrium of the forces. | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
91 | 31 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 90 | The necessary preload is very close to the admissible preload, taking into account a tightening factor of 1,5. | ASA | More clarification required to understand the discrepancy. | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
92 | 32 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 90 | One side opening and slipping should be verified against Fm min, meanwhile bolt stress, thread depth and surface pressure against Fm max. | ASA | See RIX 54 | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
93 | 33 | Benjamin Siegel | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 90 | The thread resistance depends on the threaded depth. All bolted joints seem to have the same threaded depth. Is that correct? | ASA | Since most of the bolts are M6, the same threaded depth has been considered for all of them. | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
94 | 34 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 90 | Due to the conical shape of part of the rotating structure the screws have to handle higher shear load. The exact values should be determined by FE. | ASA | All the conical elements have been designed with centering surfaces that avoid shear loads. Hence, the bolts of the joints will not suffer this type of loads. However, from the calculation point of view, the shear calculation of the bolts have been done to check these bolts could withstand shear loads. | Update the bolt calculations to obtain the load on each bolt from the FEM Analysis. Results updated on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
95 | 35 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.3.4 | 90 | The bolted joint between main rotating hub and conical hub cannot be handled with the VDI 2230 guidline being an implicit open joint (or something undefined between open and colsed joint), due to the clamping of the rotor. | ASA | See answer to RIX 16. | Redesign the clamping of the rotor of the motor to transmit the loads through the structures and not through the motor. The rotor of the motor will be fixed by bolts to the rotating structure. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
96 | 57 | Marc Dubbeldam | RIC | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.4.1 | 97 | The figure for the mass in the text is different from that in table 5-18. | ASA | There is a mistake on the text due to some final updates on the design that introduced some minor mass variations. The text will be corrected accordingly. | Update the text and the Table 5-18 with the correct mass value. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
97 | 58 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.4.2 | 98 | What quality assurance measures are in place to ensure that the bearing friction due to the preload does not (significantly) exceed the calculated value? Will Rothe-Erde accept a requirement on the maximum friction torque? | ASA | The bearing friction due to preload estimation performed from the value of the FC-Sets has also been used in previous projects, leading to realistic results. In addition, a margin of 15% has been included on the total torque calculation. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
98 | 59 | Marc Dubbeldam | RIQ | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.4.4 | 102 | What is the factor of 0.8 (to accommodate a reduction in braking force due to the non-standard configuration) based on? Is there any theoretical/imperical justification for this? What if the assumption is incorrect? | ASA | It is a safety factor assumed to reduce the braking force as the configuration of the calipers is modified. | - | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
99 | 36 | Benjamin Siegel | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.4.4 | 102 | The tangential force of the chosen brake calipers is 216 N (fail-safe type) obtaining an brake-torque of about 260 Nm without correction factor. These values should be reviewed considering the friction torque of the bearing, partial use of damper stroke (safety is covered) and counterweighting the instrument. Further, the friction force can be lower in this type of aplication (holding brake, emergency stop, low velocity) as the manufacturer states in the manual. | ASA | The force of the brakes calipers are lower than the values shown in the report. The correct value is 261.6Nm without any safety factor. However, the biggest contribution that affects to the braking of the system is the unbalance foreseen for the Instrument. Therefore, we should try to reduce this unbalance to avoid the integration of more braking calipers or bigger calipers. However, if the bearing friction is considered the braking forces will be considerably reduced. The bearing friction has not been introduced since this value has not been provided by the supplier. The calculation will be updated accordingly when this value is provided or can be updated with the estimated value with the power budget calculation. | Update the calculation of the Brake System on the Design and Analysis Report, correcting the force of the brakes and including the bearing friction using the value estimated in the power budget calculation. | Pending For Revision of Sheffield/Durham/GTC | |||||||||||||||
100 | 60 | Marc Dubbeldam | RID | P101815-HCAM-TRE-001 | Design and Analysis Report | 5.4.5 | 103 | The selected damper would not survive the scenario presented in section 5.2.6, or am I missing something? | ASA | This second accidental case has been removed. | Remove the second accident scenario of the Mechanical Limits Failure Mode Analysis on the Design and Analysis Report. | Pending For Revision of Sheffield/Durham/GTC |