VATT guide box software

Undockerized

This is now not using docker. Make the file as normal and the indiserver launcher on the desktop runs it on port 7600.

Now back to the README.

This is the new VATT guidebox software repository. This software comes in three pieces:

Control software flashed onto the guide box motors. It is called allmotors.sms.
The set of functons used to communicate with the motors
The INDI driver There is also a python module to communicate directly with the motors for testing purposes.

The motors communicate with the outside world via an RS485 serial line connected to the head node.

Control Software (allmotors.sms)

The control software (allmotors.sms) runs on the new Moog Animatics Class 5 M style SmartMotors. It was written using the SmartMotor Interface software. It is a basic-like language that has a very simple and easy to learn syntax. For simplicity and interchangeability each motor has the same version of firmware flashed onto it. The program differentiates its behavior based on the CAN address of the motor. This is very important because if a motor is given an incorrect address it can cause damage. For language specifics and anything else you might want to know about the control software refer the the developers guide .

The control program is broken into subroutines that are labeled with C<NUM> where <NUM> is an integer used to name the subroutine. You call the subroutines with the GOSUB(<NUM>) command. When a motor starts up it waits for the head node to call its C1 subroutine. When the head node is started, it waits for the user to call its C0 subroutine. C0 puts in place all the necessary settings like homing position and accel/decel rates. The head node is defined as the motor connected with the RS485 serial line. The software flow charts can be found in the diagrams directory

Motor Communication Software (gb_serial.c)

This module facilitates the low level communication with the motors. It has convenience functions for anything one would want to do with the guidebox. This includes subroutine calls, initialization, homing, goto and telemetry streaming.

INDI Driver (gb_indi.c)

The INDI driver is built with indilib though it uses an older C based version of the library and not the C++ version built by Jasem Mutlaq.

Current Implementation at VATT

The user interface for this software is the INDI webclient. The webclient displays the INDI vector properties from the gb_indi.c in a web page. There is a VATT4K version, a VATTSPEC version and an engineering version. The INDI driver and indi client are started at system boot on vattcontrol using an enabled systemd service. You can see the Unit file here. You can start, stop or reload this service using the service command or the systemctl command. Like:

sudo service webclient-compose start
sudo service webclient-compose stop
sudo service webclient-compose restart

The systemd service uses docker-compose to run three different docker contianers:

The nginx webserver
The webclient
The indiserver and drivers

The docker-compose yml file is here. One could of course run all these items outside of docker but docker simplifies the implementation. Docker can however make development a little more complicated as you have to put the new indi-vatt-guidebox binary inside the indihex docker contianer. If you wish to run the indidriver natively you can kill the indihex container and run the driver on port 7623 and all should work.

If you need to port the driver and client to another computer it should be as simple as gathering the docker-compose file and running:

docker-compose -f docker-compose-vatt-guidebox.yml up

This will download the three containers mentioned above and run them. This has not been tested and may require some tweaking.

Note: this driver runs inside the indihex docker to combine the drivers under one indiserver. Otherwise, we would need separate instances of indiserver to run the secondary hexapod and this indi driver.

Build and compile

There is a Makefile to build the indi driver. The command is simple:

make

This will buile the indi-vatt-guidebox binary. To run this in the indiserver type:

indiserver -p <port> ./indi-vatt-guidebox

The number is the port that the INDI client will use to access the indiserver. Currently for the secondary hexapod and guidebox control we use port 7623. This is ofcourse subject to change without notice here.

Deploy at VATT

Because the developemnt to deployment is a little complicate, I will walk the reader through it. Let's say we want to change something in the INDI driver (gb_indi.c), build it and set this new build as the default build on VATT. To do this you would follow these steps:

Make the changes in gb_indi.c
Build the indi-vatt-guidebox binary with make
Copy the indi-vatt-guidebox binary to the vatthex-indi source directory
build the srswinde/indihex:guidebox_indi docker container with the build.sh script
Restart the webclient-compose service with:

service webclient-compose restart

Auto Focus Routine

The optical field projected onto the guider camera is very curved, especially in the regions covered by the U-Mirror. This causes focus to be a function of the X and Y stages of the offset guide camera. This function can be modeled as the following polynomial:

33.325*r^2+0.0063*r+0.0012

r in this case is the radial distance of the guider determined by sqrt(x^2+y^2) and x an y are the X and Y positions of the guide camera.

When the user puts the INDI driver in the auto focus routine state, every X an Y move will result in a change in focus based on the above equation.

User Bits

User Bits are user defined bits on word 12 of the SmartMotor set of information bits. The allmotors.sms defines them thusly:

User Bit	Description	Read Command	Which motors
Bit 0	Is Homed	RB(12,0)	All Motors
Bit 1	Motor 1 OK	RB(12,1)	Head Node
Bit 2	Motor 2 OK	RB(12,2)	Head Node
Bit 3	Motor 3 OK	RB(12,3)	Head Node
Bit 4	Motor 4 OK	RB(12,4)	Head Node
Bit 5	Motor 5 OK	RB(12,5)	Head Node
Bit 6	Motor 6 OK	RB(12,6)	Head Node
Bit 7	Motor 7 OK	RB(12,7)	Head Node
Bit 8	Fwheel Moving	RB(12,8)	FWHEEL_UPPER
Bit 12	Motor Ready	RB(12,12)	All Motors

IO definitions and other motor specefics:

OFFSET_X (CAN ADDRESS 1)

The Offset X motor uses an LED and IR sensor to home. The IR light is blocked from the sensor for the entirety of travel except for a small hole that allows light through at the home position.