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There is an experimental triangular machine tool in the large broom cupboard behind the door in Dinky that can cut steel, aluminium, resin, plastic, PCBs and moves very fast. It is under-going continual technical development. No one really knows how to use it, but see Julian (@goatchurch) for details.
How to log on and make it work
The machine is connected to the router in Dinky via a ethernet cable. It's mac address is 84:eb:18:e2:72:17. Find it by either:
sudo arp-scan 10.0.29.0/24 | grep 84:eb
nmap -p22 10.0.29.255/24
and look for an open port. Then logon (using the correct IPnumber) with:
ssh -X firstname.lastname@example.org
The welcome message will provide you with the password. The '-X' is to enable the machinekit X-Windows interface to tunnel through your ssh connection. Now type the following commands (the '.' is important in the second command):
cd machinekit . scripts/rip-environment machinekit mk7_bbb_pcb.ini
When the "Axis with Machinekit" controller window pops up, you can arm the servo drivers by first checking the emergency stop button is out and then closing the circuit between the ERR/RES and ENC+ (two slots down) with the yellow wire in each of the three Gecko drivers. Now toggle the machine power (orange square button to the right of the Estop circular red button in the control window) and you will be able to jog the axes using your cursor keys for the table and arm and PgUp and PgDown keys for the Z-axis.
If a motor isn't working check the gecko servo driver hasn't tripped off (red fault LED) and the fuse hasn't blown. Only use quick-blow 2A for Z and 3.15A on table and arm motors. These are intended to prevent the machine doing damage by limiting any power surges that the motors can apply.
Now click on the [Home All] button so that each of the three axes moves and makes contact with the limit switches and is aware of its position. You are only now able to run any G-code.
Switches, coordinate systems and monitoring
From the "Axis with machinekit" window, click on [Machine] | [Show HAL Configuration] and click on the "watch" tab and select under "Signals" all-home, probe-in, switchtestx, switchtesty. These are the GPIO pins that feed back into the controller for positioning and homing. (All motion is relative, so it needs to start with an absolute known position and work from there.)
The configuration of which pin does what and whether it is inverted is controlled by the HAL file, and the transformation from XY coordinates to non-cartesian table/arm joint positions is done in mk6skins.c. For more see bbhquad/arcitypecalibration.
All conversion parameters are set according to the dimensions of the machine, except the plane rotation, which can be set under the "Show" tab of the HAL Configuration with "kins-rotrad" (in radians). The command to change it is:
setp kins-rotrad 2.76784
- Build area 250mm x 250mm x 100mm
- 3x Siboni 30PL082 servos, US Digital E5D rotary encoders, Geckodrive G320 drivers.
- Spindle is ER16 High Speed Spindle - 0.75kW (1HP) - 24000rpm with a Frenic mini inverter.
- There is a selection of small carbide and HSS tools with collets, clamps and bolts, and a vice
- Runs Machinekit for Beaglebone through our own PCB wiring setup -- designs are at bitbucket/bbhquad
- R1610 C5 ballscrews
- Arcitype Bill of materials
- Better clamping technology and knowhow
- Touch pad to align the vertical position of the cutter
- Probing tool to find the position of clamped stock and to scan objects