NEW ‐ How to control Target motor ‐ Run IV - PADME-Experiment/padme-fw GitHub Wiki

PADME Target Notes

These notes serve as a practical guide for operating the PADME target system. The first section describes how to set up the hardware connections, including cabling, power supplies, digitizer, network, and control systems, with illustrative pictures provided where useful. The second section focuses on the currently adopted Ethernet-based control system, detailing its functionalities, software interface, monitoring tools (including camera and position tracking), and usage instructions. The third section explains how to control the target movement using the legacy CAN-USB controller, although this is no longer the standard.

All the credentials needed are written on the "target pc access" ELog entry of 07.05.2025

Table of Contents

Hardware Set-Up and Connections

The Active Diamond Target detector area is the one between the DHSTB002 BTF magnet and the PADME magnet. The Run IV target position has been moved downstream by 30 cm. Starting from the gate valve of the beam pipe, there are 2 components before the PADME vacuum chamber: the bellow and the cross, where the target is. The whole target front-end electronics is inside one of the cross arms, namely on the door side. The target can be moved in and out of the beam line with a system of a Pfeiffer and Nanotec stepper motor, controlled with a Nanotec motor controller (USB-Can controller during first 3 runs and an ethernet controlled one during Run IV). A small camera and a Gefran Transducer are installed for movements monitoring.

The system is powered by two HV power supplies: one for the target at -250 V and one for the motors at 24 V. This is based on the N5 controller manual:

Download Nanotec documentation

Ethernet-Controlled Motor Controller

The N5 Nanotec controller is managed using Plug&Drive (Windows) on the Target PC. For remote control, use Team Viewer application

Download TeamViewer

In order to really control the motor, the procedure consists in connecting the controller, setting the proper configuration values and do operations using NanoJ codes or directly the graphic interface. NanoJ codes are written in a syntax similar to Java and C++ (Reference - NanoJ code)

Reminders:

Position References

  • On-beam: 5.15 cm / 170 (potentiometer)
  • Out-of-beam: 0.2 cm / 871 (potentiometer)

Potentiometer Calibration

The potentiometer has a 100 μm precision. Active range: 7.5 cm. Mechanical range: 8.5 cm.
Initial calibration (05.05.2025):

$$ \Delta V = -142.6(2) \cdot x + 903(1) $$

Where $$\Delta V$$ is the read voltage, $$x$$ is position on the ruler.

Gefran Transducer Info

End-of-Run Info

Mechanical stops:

  • Out-of-beam: beyond 0 cm, approx. 900 (potentiometer)
  • On-beam: above 5.8 cm, approx. 50 (potentiometer)

If hit, reboot the system. NB: Figuring out that you have hit an end-of-run is not so easy from remote, so be careful!

Procedure

  1. Launch Plug&Drive software
  2. Connect the controller in Recently Used selecting its IP address: 192.168.62.200
  3. Check the setup configuration under Setup → Drive and Setup → Current:
    1. Drive: check the values under both the Motor and Brake sections. Motor → Motor drive submode select Stepper, Pole pair count 50, Step angle 1.8. Brake → all the time should be 100. We operate in Open Loop mode.
    2. Current: all the current values should be 2000 mA, that is the maximum current supported by the motor. To be noticed: Open loop current reduction value/factor usually takes random numbers when restart the software, it has to be 50%.
  4. Move the target using NanoJ codes or operating in Profile Velocity/Position (which is not currently operational) mode.
    1. NanoJ: currently we are using the NanoJ codes only to verify if the controller works and receives commands. Pressing the button of the NanoJ operations, a window with a tutorial code for Profile Velocity mode will appear. Running this code you move for a second the motor in a direction and for an other second in the opposite direction to leave the target in the original position. After these two movements, it will reset all the variables used to the starting values
    2. Graphic Interface: currently we can move the system only in the Profile Velocity mode. This mode consists in selecting the speed (negative = on beam direction, positive = out of the beam line) and activate the operation until the operator presses quickstop. The suggested speeds are in between -10 and 10 (no units here, just the number you can see on the panel), with a value ~|2| for the fine tuning.

Author: M. Mancini. for more information or the pdf version, please contact [email protected]