Sunday 3 February 2019

Tim's XY Plotter Tool Holder


Tim's XY Plotter Tool Holder
This is part of my Blog here: Tim's XY Plotter


Over time and several iterations my Tool Holder has evolve into the following:


It is a frame with a servo for raising and lowering the tool, two 3mm linear rods to guide the tool in the vertical axis.



The Tool Attachment is connected to the servo arm by a Connection Rod.

The Connection Rod is made from bent stiff wire (0.8 - 1mm) and has a spring attached to keep pressure on the Tool Attachment.
In the up position the Tool Attachment is held up by the hook at the bottom of the connector.
In the down position Tool Attachment is pushed down by the spring.
The Tool Attachment has bushes on the left side to keep things accurate.
(The linear rods and bushes, I salvaged from old CD/DVD drives)

I have currently made several Tool Attachments for it:
Pen Attachment. (holds similar items)
Knife Attachment. (used to cut vinyl sheets)
Rotary Hobby Tool Attachment. (used for drilling and engraving)
Laser Attachment. (used for cutting and engraving)(1W 1.5W & 15W versions)
Router Attachment.

The Pen Attachment:


The parts (Pen Holder Slide with Bushes.stl, Pen Clamp.stl, Pen Clamp Tensioner.stl) for the Pen Attachment can be found in this post: Tim's XY Plotter Parts list.


Also required:
Two M3x25mm set screws.
Two M3 square nuts.
Four small self tapper's.
Two 3x4x4mm Bushes.

Fitting the Tool Attachments is done by sliding the two 3mm dia. linear bar's up out of the Tool Holder, hold the Tool Attachment at 90 Degrees to the Tool Holder and sliding in the Connecting Rod into the slot at the top of the Tool attachment, then rotating the Tool holder to it's correct orientation, then sliding the linear bars back into place.

Because the Tool Attachment has bushes on the left side I have made a clip to stop the bar lifting out of location.







The Knife Attachment:

The Knife Attachment requires the purchase of a Knife Holder. eBay Search.

Two parts need printing:

STL Files:
Knife Slide with Bushes 002.stl
Knife Clamp 002.stl

Also required are:
Two M3x25mm set screws.
Two M3 square nuts.
Two 3x4x4mm Bushes.

    


Self adessive Vinyl is easier as it has a backing to hold things down.
Once you get a costume to setting the depth of the blade and pressure to apply, things improve.

Made a decal for my computer.


With this attachment I have modified one of the blades into a Scribe.
I use the Scribe for making my own PCB's.
I have done a blog here: Tim's PCB (Plotted Circuit Board).

    


Rotary Hobby Tool Attachment:


The Rotary Tool Attachment is similar the Knife Attachment with the addition of extra pieces so the Rotary Tool can be set at an angle.

Four parts need printing:

STL Files:
Drill Mount 002.stl
Drill Mount Slide with bushes.stl
Drill Mount Locator Disc.stl
Drill Mount Clamp.stl

Also required are:
Two M3x25mm set screws.
Two M3 square nuts.
Eight M3x10mm self tappers.
Two 3x4x4mm Bushes.
This holder has been designed to hold a RoraCraft RC200X. the diameter of the grip is 16mm.


The Drill Mount Locater Disc goes behind the Drill Mount and secured from the front with four self tappers. The Drill Mount is also secured to the Slide by four self tappers.
The square nuts are placed in slots on the Drill Mount and the Clamp is secured into them with set screws.

1.5W Laser Attachment:

The 1.5W laser Attachment requires the purchase of a 1.5W laser. eBay search.
I also made a driver for the laser.


Prior to the 1.5W Laser, I purchased a 1W laser. eBay Search.
This mount will hold either one, but the 1.5W is a big improvement. eBay search.

         

1W
1.5W
Comes with metal Heat sink
No Heat sink (does no need one)
12mm dia.
½” dia. (does not fit 12mm heat sink)
Good for engraving
Will cut corrugated cardboard



As the 1.5W laser did not fit the 1W laser Heat Sink, I replicated it with a plastic one so the 1.5W laser fitted the same way I had fitted the 1W laser.

The laser attachment still slides on the two rods like the other attachments, but is not attached to the Servo, there is an addition of an adjustment screw. After setting the focus of the laser, adjustment for different thicknesses can be done a lot easier with this screw.
The laser is set at least 100mm from the work surface to sharpen the focal point.

Seven or Eight parts need printing:

STL Files:
1.5W_Adjusting_Screw.stl
1.5W_Laser_Adjustment_Nut.stl
1.5W_Laser_Adjustment_Screw_Support.stl
1.5W_Laser_Driver_Support.stl
1.5W_Laser_Fan_Mount.stl
1.5W_Laser_Heat_Sink.stl
1.5W_Laser_Holder.stl
1.5W_Laser_Slide_(4mm).stl

Also required are:
Twelve M3x10mm self tappers.
Two 3x4x4mm Bushes.
And as mentioned I made a driver for this laser, I will do a separate post for making this when I get time.
For now here is the circuit:

    

 

Router Attachment:

The Router Attachment has an added stepper motor to rise and lower it.
Has a driver board for the stepper and a switch for the spindle motor.
(To get high spindle speeds, the motor has a higher voltage than the plotter)

10 Colour Pen:

The 10 colour pen attachment uses a cheap multi colour pen from China.
I modified the top and added a motor to select the colour I need.





To Be Continued






I have a web site as well: Tim's Place Mirror: Tim's Place




Tuesday 29 January 2019

Bluetooth Module Configuration



Configuration of the Bluetooth Module


This is part of my Blog here: Tim's XY Plotter

There are two main types of Bluetooth Modules the 6 pin HC-05 and the 4 pin HC-06
 
When fitted it only uses the middle 4 pins.

To configure a Bluetooth Module requires communicating with the device using "AT" Commands.
Not all manufacturers use the same commands, they use similar commands with slight differences.
I have seen many versions of Bluetooth Modules on the market, 4 pin, 6 pin, HC-05, HC-06 and HC-10.
So downloading the right data sheet and manual is essential.
This information refers to the two above. (If I get any of the other types of modules I will update this to suit)

Bluetooth Modules have 2 main communication modes:
1. Data mode.
Where data is just sent and received.
2. Command mode.
In Command mode, "AT" commands can be sent to the device, to make it do tasks.

The HC-05 6 pin Module needs the CMD pin High or Low to set the mode. (The breakout board usually has a button)

The HC-06 4 pin module automatically changes to Data Mode when connected to a Paired Device and to Command Mode when not connected to a Paired Device.

I have one of these which I use to configure my Bluetooth Modules, I like because it has jumper to select Logic Level Voltage. Which means I can connect the Bluetooth Module direct.
eBay Search USB to UART If you have one of these, you could use it instead of using an Arduino UNO.

I will show how to do it with USB to UART Device after I show how to do it with an Arduino.

WARNING
Not all Bluetooth Modules can accept a 5 volt data line.
Although a Bluetooth Module may be advertised as 5 volt compatible, this may ONLY refer to the Power Input. The  Data connections (RXD and TXD) may only be 3.3 volt.
Putting 5 volt on the RXD pin will destroy that input pin on the UART chip.

So, because the Arduino UNO has 5 Volt data pins, some form of voltage reduction is required.
You can use resistors to make voltage dividers on each data line, but I prefer to use MOFETS.
You can buy a Logic Level Converter on eBay.

This is a board I have made and use for other projects.
Here is the fritzing file if you wish to make one: 3 volt to 5 volt PCB.fzz



Here is a breadboard Circuit using the Logic Level converter bought on line to make things simple.

The circuit:

The Arduino sketch:

Bluetooth_configuration_sketch.ino

The Bluetooth devices UART speed are set to 9600 by default in Data Mode.
So, using the sketch above in data mode, may need the BTS.begin(38400) changing to BTS.begin(9600). (or if you have changed the UART speed, to what ever you have changed it to.)
When in Command Mode, Commands may be able to be sent at 38400. (depends on how command mode was set.)

I change 2 things: The device name and the device UART speed.
The Name of the device I will be changing this one to: "Tim's Plotter". (it can be whatever you want)
This is the name you see when pairing the Bluetooth device.

The speed is dependant on how it is connected.
There is a limit if it is connected to soft serial, this is: 57600bps.
This is how it is connected above. (Soft Serial)

However, on my Plotter Controller, I am going to connect it to pins 0 and 1, hard serial (the serial chip). The same pins the USB uses, which I set at 115200 when using the USB to communicate with the plotter.

So at the end of the day I will be setting the speed of the Bluetooth Device UART to 115200.

This means that once the speed is set, any other changes may need a USB to UART Device to communicate with it, the above may not work.

Well you may be able to use the above at 38400 if you can boot the device in Command Mode.

Check it is working first.
Connect it up as shown above and connect a USB to the Arduino UNO so that all is powered up.
My Bluetooth Device has a red LED that flashes quite rapidly in data mode, waiting to connect.

Pair the device with your computer. It's default name will be something like HC-05.
The Password will probably be: 1234 (HC-06) or 000000 (HC-05)
After you have paired the device with your computer, you should be able to see it listed in the com. ports in the Arduino IDE.

You don't want the Bluetooth device connected to another Paired Device when setting it to Command mode.
When in command mode communication will be through the USB connected to the Arduino UNO, with the above sketch installed.

Command mode (HC-05) is set with the CMD pin (pin 34).
The module I have has a button connected to this pin.

With the CMD pin pulled to logic level 0, or left open. The Bluetooth Device will start in Data Mode.
By setting the CMD pin to Logic High. The Bluetooth Device is set to Command Mode.

Command Mode can be set in two ways:
While powering up. (The UART is set to 38400bps, 8 data bits, 1 stop bit, no parity, no handshake)
After powering up. (The UART is set to what ever it was set to using the AT+UART Command)
(The HC-06 module automatically changes to Data Mode when connected to a Paired Device and to Command Mode when not connected to a Paired Device.)

The "AT" commands for the HC-05 and HC-06 are similar but have slight differences.
So I will put HC-05 in Bold and (HC-06 in Italic) in brackets.

The AT+UART (AT+BAUD) Command is what will be used to set the Data UART speed to 115200.

What I do for the HC-05, is have it all powered up as shown above and unplug the Bluetooth Device from the Breadboard, then holding the button pushed in on the Bluetooth Device, plug it back into the Breadboard.
When plugged in and the LED lights up I let go of the button. The LED now flashes at a slow rate.
Because the CMD pin was Logic High when powering up the UART should be set to 38400.

In Arduino IDE, set the Com Port to whatever the Arduino UNO is connected to.
Now to open the Serial Monitor from the Tools Menu in the Arduino IDE.



Set the baud to 38400 in the Serial Monitor.
Make sure "Both NL & CR" are set. (All commands must end with Carriage Return and Line Feed)



"AT" commands can now be sent.

To make sure all is OK, type AT (AT ) and click Send.



After the Send Button is pressed, OK should be returned in the output window.



If the Bluetooth Device returns OK, then all is good.

Now commands can be sent to change the settings.

Name:
To check the current name type: AT+NAME? (AT+NAME)

To set the name type: AT+NAME=Tim's Plotter (AT+NAMETim's Plotter) (can be any thing after the equals sign (no equal sign), up to 31 characters)

Type: AT+NAME? (AT+NAME) again to check all is OK.




UART speed (BAUD):
There is a big difference in setting the UART speed on each version of the devices.

To check the current UART speed: AT+UART? (AT+BAUD)

HC-05 may return a different speed than the one set in the Serial Monitor, this is OK, the speed currently connected at is the safety speed at boot up, that is, if Command Mode is initiated at boot, the speed will always be 38400 so it can be reset.

Also:
HC-05 returns: Baud, Stop Bit Code, Parity Code
HC-06 returns: Baud Code

So:
HC-05
baud = any one of the following:
4800
9600
(default)
19200
38400
57600
115200
234000
460800
921600

1382400

Stop Bit Code = one of the following:
0 = 1 bit (default)
1 = 2 bits

Parity Code = one of the following:
0 = None (default)
1 = Odd parity
2 = Even Parity

HC-06
Baud Code = one of the following:
1 = 1200
2 = 2400
3 = 4800
4 = 9600
5 = 19200
6 = 38400
7 = 57600
8 = 115200
9 = 230400

To set the UART to what my controller will be using to communicate with the Bluetooth Device,
type: AT+UART=115200,0,0 {baud, stop code, parity code} (AT+BAUD{baud code})

Type: AT+UART?  (AT+BAUD) again to check all is OK.



From here on in Data Mode, communication can only be done at 115200.
Also HC-06 Command Mode.

If ever the Bluetooth Device (HC-05) UART needs changing to a lower speed to be used on Soft Serial, it can be connected at 38400, if booted with CMD pin set High at boot time.

To query the Password, the command is: AT+PSWD? (AT+PIN)
If the Password needs changing, the command is: AT+PSWD=1234 (AT+PIN000000) (replace numbers with alphanumeric password 16 characters max)

The Bluetooth device is ready to be plugged into the Plotter Controller Board.


Using and connecting the Bluetooth Module to the PC with a USB to UART device is much easier.


To connect the two devices, I used two Socket headers (an X5 and a X4 header) soldered together with the outer pins joined with a wire.
NOTE! The jumper is set to 3.3volt. (this is the data voltage)

The circuit:


Instead of using the serial monitor in the Arduino IDE, I have made my own Serial Monitor application.

Tim's Serial Monitor.



Using this Serial Monitor, I connect just as I did with the Arduino IDE Serial Monitor.
It has some pre-sets that you can change to what ever you like, it makes it quicker than typing most used phrases over and over again.
Also I have added notes about Bluetooth, The Notes can be edited to what ever.

The plot plots Numeric data received.


My Serial Plotter does not draw data very fast, so if data is received too quickly, it is placed in the serial ports buffer and plotted as soon as my application can plot it. (not expert as programming)


Finding which COM Port is attached to which Bluetooth Device in Window 10.
Open the Settings window and chose Devices (Bluetooth, printers, mouse).
1. Click More Bluetooth options on the right. (It may be below, depends on how big you have the settings window.)
2. Click the COM Ports tab in the new Bluetooth Settings window.

You should see all the Bluetooth devices that have been paired with your computer.
Each Bluetooth device has two COM Ports allocated to it.
One for incoming data and one for outgoing data.

When selecting a COM Port to a device in software, you normally chose  the Outgoing COM Port.


List of my other Blogs.

I have a web site as well: Tim's Place Mirror: Tim's Place