CNCTRK AZ/EL Positioning Unit Assembly Instructions. Rev

Transcription

1 CNCTRK AZ/EL Positioning Unit Assembly Instructions Rev Introduction/Overiview The AZ/EL Positioner Unit, RAZEL, consists of two stages of identical gearboxes joined together with a Configuration Adapter. One may have chosen to purchase and use a single stage of the assembly, RAZO, to make an AZ-Only positioning unit. Either of these configurations can be controlled by the real-time open source software LinuxCNC ( on a suitable computer, laptop, or using the Raspberry Pi based controller, RASPI, or by using custom software on any platform. These instructions will guide the user through the process assembly of the RAZEL Kit (or the RAZO Kit) in preparation capability using the CNCTRK system. Details of setting up tracking are covered in the May/June AMSAT Journal article of the mechanical for full tracking software for satellite on the CNCTRK system. The components needed for satellite tracking using CNCTRK consist of only a suitable computer running the LinuxCNC (with parallel port and cable), a power supply, and the AZ/EL Positioning Unit. A complete tracking system running GPredict and LinuxCNC is shown in the photograph below. [[[Tracking System Components (less RF Gear)]]]

2 Parts Identification Before proceeding with assembly, identify and verify that all the necessary parts that are required in the assembly are contained in the package received from FRFMW. The quantity and identifying features and descriptions of the necessary parts are listed in Table 1, below. [[[AZ/EL Unit Parts]]]

3 TABLE 1 Item No List of Parts With Reference Identification Description AZ_Plate_disc Bearing_Cap AZ_Housing Motor_Driver_Mount (deleted) Configuration_Adapter (obsolete photo) (deleted) AZ_Shaft 4 inches AZ_Shaft_Worm 5 inches EL_Shaft_Upper 8 inches Qty 1 6 Worm_Gear_Kit Stepper Motor Motor Driver Bearings DB5 Female Connector Standoffs, DB5 Connector, 4-40 x TBD Long Wire and JST XH 6pin Motor Conn., Stranded Screws 8-3 x 1/ SHCS Screws 8-3 x 5/8 SHCS Screws 8-3 x 1 SHCS Spacer, Nylon 3/8 OD x.194 ID x 1/ LG Spring Pin, 5/64 diameter Flat Washer 1/ Jackscrew. Long A/R CAUTI: The motor and shafting are provided as a matched pair of components. This is due to the fact the motor shaft is match drilled for the roll pin to shafting interface. Alignment is marked by a small dimple on the motor and shafting. These parts should remain together as a pair for smooth operation and may be delivered already assembled. Once all parts are verified to be complete, proceed to AZ Stage Assembly.

4 AZ Stage Assembly AZ01. Install four (4) Spacers onto the bottom of the AZ Housing using four(4) Socket Head Cap Screws. This step enables the AZ Housing to sit flat on a work surface. AZ0. Select a Gear Kits and pick the following components for use in the next assembly step: Large Diameter Plastic Gear Collar Large Roll Pin 1/" Washer 0.06" thick (this item not from the gear kit) AZ03. Pick the four inch (4") long Shaft from the package and using large pliars (preferred) or hammer install the Roll Pin into the AZ shaft. AZ04. Assemble a total of three (3) Bearings and three (3) Bearing Caps onto the AZ Housing in the locations indicated in the figure below. [[[AZ Housing with Three Bearing Locations]]] Fasten the Bearing Caps using #8-3 Socket Head Cap Screws (SHCS) and leave screws loosely fitted (i.e. un-torqued) for the present time. Now, temporarily remove the TOP Bearing Cap and Bearing.

5 AZ05. With the AZ Housing standing on one of the open ends, feed the clear end (no dimple) of the AZ Shaft through the TOP opening; the fit is close but will not offer significant resistance if aligned properly. Continue to feed the Shaft pregressively as the parts are installed, taking care to align the Roll Pin with the notch in the gear as needed to engage these components. Install the following items on the shaft in order: Large Plastic Gear Collar IMPORTANT NOTE: The plastic gear may have a "U-shaped" notch and a "V-shaped" notch to accept the roll pin; use the "U-shaped" notch, else excessive bearing pre-load may result. Use of a file on the plastic gear notch may be required to enable the pin to seat fully into the gear. AZ06. Feed the Shaft through the bottom Bearing and, using a 1/8" Hex Driver, tighten the two Collar set screws hand tight to secure the AZ shaft in place. Verify the shaft does not protrude beyone the plane of the spacers on the bottom of the unit. Re-install the top bearing and bearing cap. The AZ Shaft assembly into the Housing should look like the photograph below. [[[AZ Shaft Inserted In Housing]]]

6 AZ07. Collect the following items in preparation for the AZ Motor and Worm Gear assembly: Stepper Motor Five Inch (5") Shaft (matched to motor) Motor Mount Plate Roll Pin, 0.080" Roll Pin, 0.171" One 1/" ID spacer (bronze color) Worm Gear from the Gear Kit bag AZ08. Install the Motor Mount cut a flat on the nylon spacer motor mount). Visually center feature and assemble with four recommended value. Plate onto the AZ Housing. (NOTE: Use a knife to to eliminate an interference condition with the the plate in the middle of the slotted mounting (4) screws. Torque the four (4) screws to AZ09. Position the five inch (5") Shaft over the Stepper Motor shaft and press the 0.080" Roll Pin into the shaft until flush. Waterpump or wire pliars are suitable for pressing the small Roll Pin (see photograph below). [[[Photograph of Roll Pin Installation]]] Similarly, press the Roll Pin into the five inch (5") Shaft until approximately equal lengths are observed on each side of the Shaft. The fit is tight; a light tap with a hammer may be required. AZ10. Feed the Five Inch (5") Shaft (with Stepper Motor attached) through the available hole in the Motor Mount and partially into the AZ Housing. AZ11. Install the following items onto the Shaft, in order: Worm Gear with notches facing Motor Mount Spacer, 1/ inch long

7 Align the Worm Gear with the Roll/Knurled Pin and slide gear toward the Mounting Plate until the pin is engaged in the Worm Gear. If needed, remove the gear and use a file on the gear notch to seat the pin, similar as above. AZ1. Assemble the Stepper Motor onto the Motor Mount while feeding the shaft through the bearing; rotate the motor as needed to position the electrical connector toward the connector mounting feature of the bracket (the #4-40 threaded holes). Secure in place using four (4) screws; tighten screws only snug -- just enough to join the units together for inspection. AZ13. Tighten six (6) screws to secure all Bearing Caps in place (NOTE: tighten to snug fit only as full torque is not required in this application and will warp the components). AZ14. If needed, adjust the Motor Mount for proper gear mesh. Turn the motor shaft by hand to assess the gear mesh for excessive binding or excessive backlash. If adjustment is needed to improve the mesh, remove the motor and shaft assembly, adjust the position of the Motor Mount to increase the mesh (i.e. gears closer together) or decrease the mesh (i.e. gears farther apart), and re-assemble as before. AZ15. Once a satisfactory mesh is achieved, torque four (4) motor mount screws. AZ16. Assess the assembly. If gaps greater than 1/3" remain on the bearing-end of the shaft, add additional flat washers to reduce the gaps, and thus, the potential end play of the Worm Gear. AZ17. Lubricate the two gears. Turn the motor shaft by hand and apply the grease uniformly over BOTH gears; a small brush may be useful. Rotate the worm drive shaft several times to distribute the lubricant and check for smooth operation. AZ18. Once the gear asssembly operates without binding, application of a threadlocker compound is advised to keep fasteners held in place securely. At this point we have an assembled gearbox that is suitable for use in the RAZO, AZ Only, application see photograph of completed AZ Stage below. The motor driver electronics could be installed at this stage but, instead, the driver installation is held for a later time as this allows the completed assembly to serve as a reference for the second (Elevation) gearbox. [[[Photograph of AZ Stage Assembly]]]

8 EL Stage Description (Skip for AZ-Only Units) The EL Axis Gearbox uses many parts that are identical to those in the AZ axis unit. For reference, the differences are itemized below: a. The EL axis gearbox omits the four spacers used as feet in the AZ axis b. The Motor Mount is rotated 90 degrees relative to the AZ axis application c. The EL axis Shaft is eight inches (8") long EL Stage Assembly EL01. Repeat the steps AZ0 through AZ07, substituting the 8" Shaft for setp AZ05. EL0. Repeat the steps AZ08 by rotating the Motor Mount 90 degrees as depicted below. [[[Photograph Showing 90 Degrees Rotated Motor Mount Bracket]]] EL03. Repeat the steps AZ09 through AZ19, using the completed unit as a reference. EL04. Pick the following parts needed to complete the EL axis gearbox assembly: Configuration Adapter Plate AZ Disk and two () #8-3 x 5/8" SHCS 10 ea. #8-3 x 1/" SHCS EL05. Using four (4) of the 1/" SHCS, screw the AZ Disk onto the Configuration Adapter Plate and torque the screws. Install the two longer SHCS into the AZ Disk (these will serve as set screws). NOTE: This Configuration Adapter plate assembly is placed directly on the output shaft to serve as an antenna mounting platform for the RAZO Azimuth-only unit.

9 [[[Configuration Adapter (obsolete model shown)]]] EL06. With the AZ Disk facing outward, screw the Configuration Adapter Plate onto the end of the newly assembled EL axis Gearbox and torque the six (6) screws. [[Completed EL Gearbox]]] This completes the assembly of the EL Axis Gearbox. will now be joined together in the following steps. The AZ Gearbox and EL Gearbox

10 AZ/EL Unit Assembly AE01. Place the AZ Stage on a level surface with the exposed Shaft positioned vertically. AE0. Place the EL Stage unit over the AZ Stage and position the AZ Shaft into the AZ Disk and Configuration Adapter. Position the AZ Shaft as needed to engage the (SHCS) set screw into the (single) conical hole in the AZ Shaft. Torque both set screws to value. Again, for permanent assembly, the use of a threadlocker compound my be desired. [[[AZ/EL Unit Assembly Side View]]]

11 [[[AZ/EL Unit Assembly]]]

12 AE03. Pick two () Motor Driver Circuits, two () Cable Assemblies, and two () #4-40 SHCS from the packaging. Assemble the Motor Driver circuits onto their respective axes locations. [[[Motor Driver Circuit Mounting Location]]] AE04. Wire the Stepper Motors as depicted in the following photograph. [[[Photograph of Stepper Motor Connector Wiring]]]

13 AE05. Wire the Power and Control Connector as depicted in the following schematic. IMPORTANT: Note the power supply wiring (through the service loop) to the Elevation axis motor driver employs at least two conductors connected in parallel, as shown in the diagram below. This is required in order to reduce the voltage drop across these relatively small wires. Failure to use the parallel wired supply conductors will cause drive failure at lower supply voltages. [[[DC Power and Control Wiring and Cabling Diagram (wire colors may vary)]]]

14 AE06. Assemble the Power and Control Connector onto the AZ/EL Unit Assembly, as follows: a. b. Pick spacers and #4-40 Jackscrew hardware Mount the connector as shown below [[[5 Pin Control Connector Mounting]]]

15 AE07. Route cabling to accommodate rotation about the AZ axis with a service loop as shown in the photograph of a completed AZ/EL Unit below. [[[Completed AZ/EL Unit Assembly]]]

16 Alternative AZ/EL Unit Assembly AE08. Due to the modular design the AZ/EL Unit can be assembled in more than one configuration. This alternative approach allows the two axes to operate without relative motion between the two gearboxes. However, the assembly is no longer suitable for sitting on a work surface and must be mounted only by the shaft extending from the base of the assembly; a photograph will make this more clear. The alternative configuration is achieved by inverting the Azimuth gearbox and joining the AZ and EL gearbox units together in a rigid configuration. The same Configuration Adapter is used to join the gearboxes. A photograph of the alternative assembly mounted on a tripod is shown below. [[[Alternative Configuration with Inverted Azimuth]]]

17 Antenna Mounting Kit Assembly Antenna mounting hardware is provided with the AZ/EL Unit Kit. MK01. Two fiberglass tubes provide extensions of the Elevation axis shaft. Slide the fiberglass tube over the Elevation shaft and clamp securely using the split collar clamps provided (see photograph in step AE07 above and inset photo below). Repeat for the opposite side of the AZ/EL Unit if mounting two antennas. U-Bolt brackets are provided for the other end of the fiberglass tube to facilitate antenna mounting. Proceed as follows. MK0. Insert the 1/ x aluminum rod into the fiberglass rod until the end is flush. This rod prevents crushing of the tube. MK03. Install the U-bolt bracket onto the tube using the inner pair of u-bolts and tighten securely. MK04. Similarly, install the Antenna onto the U-bolt bracket using the outer pair of U-bolts; tighten securely. Similar hardware may be used to implement a counterweight system, if needed. Illustration of Mounting Kit hardware use is shown in the photograph below. [[[Antenna Mounting Kit Use with Split Collar Detail (inset)]]]

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19 APPENDIX STEPPER MOTOR DRIVER INFORMATI CNCTRK NOTES: Both Enable pins are tied to ground in CNCTRK CNCTRK Motor Drivers have current limit set to 1 Ampere, as shipped. Mode Switch Settings: M1 M M3 MOD 1/16 ustep ( for CNCTRK) Information from Driver Supplier's Notes: One Axis 4.5A Stepper Motor Driver Borad Controller TB6600 Chip, support most parallet softwares KCAM4, MACH3 etc. 1 Axis TB6600 CNC Stepper Motor Driver Borad Controller DC : 1-36V Motor : 4,57,86 1, new type of dual polarity constant current chopping technology;, with automatic half flow function; 3, input pulse peak frequency up to 15 KHZ; 4, support 5 kinds of segmentation choice: 1, 1/, 1/4, 1/8, 1/16; 5, has the current 0.7 A 4.5 A stepless adjustable function 1. As shown above POWERIN power input interface, as shown above left negative ultra-right is positive, ~~ 50V input voltage 1.. STEP DIRVER PORT is stepping motor interface, from left to right definition A is B +, B -, A +, A 3. CTR PORT is input control interface,, from left to right in turn definition is DIR -, DIR +, STEP -, STEP +, EN -, EN + 4. MOD SW is working mode selector switch, as shown in figure, from the top to the bottom of a single definition is M1, M, M3, LATCH, which control the driver the breakdown of the selection and error reset mode M1 M M3 MOD Free, Motor don't lock 1 subdivision A mode,1/ subdivision B mode,1/ subdivision 1/4 subdivision 1/8 subdivision 1/16 subdivision Free, Motor don't lock ( for CNCTRK) Attention: as shown in figure 3 shows, switch to the left dial is, switch dial the to the right is LATCH: : automatic recovery mode, : manual recovery mode.

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