• D.R. Myers[1]
• 27^th January, 1998

LHC Experiments - Joint Controls Project
Initial Project Plan

Background

Following discussions over an extended period, there is now a consensus that there are only few, if any, technical requirements which would justify that the LHC experiments each develop independant control systems. The so-called "Thursday Club" has thus identified this area as one in which the use of resources may be optimized by working in common. A proposal for a joint project was distributed by T. Virdee and, with minor modifications, this was accepeted by those concerned at a meeting on December 12th, 1997 [1]. Some key points from this paper are:

• The scope of the project should respect compatibility with the DAQ.
• The project should be managed by a Steering Group composed of (a) two representatives from IT/CO group (one as Chairman); (b) the DCS coordinator and a DAQ representative from each experiment; (c) ex officio the LHC Team Leaders and the Deputy Division Leader of IT (or his representative).
• The project should ultimately report to the LCB.

Objectives

The primary aims of the project are to:

• Understand and describe the needs of the experiments in the domain of controls. This includes the establishment of time-scales and milestones for the different sub-systems in addition to the specific technical requirements.
• Define, select and/or implement as appropriate the architecture, framework and components required to build the control system; produce guidelines for hardware interfaces and communications protocols.
• Where interim solutions prove to be necessary, help with their provision.

Procedure

A Project Team coordinated by the project leader, will be set up consisting of people proposed by the experiments and IT/CO. This team will establish a preliminary list of work-items, each of which must be defined by its Objectives, Scope, Milestones and an estimate of the resources required. This list will clearly not be definitive and members of the Project Team may propose additions and changes in the future as deemed necessary. The Steering Group will meet regularly to review work items, to agree on their relative priority and to ensure that the necessary resources are available. Every effort should be made to proceed by consensus after technical discussion.

It is proposed by way of simplification to divide work items into four principle categories:

An information system will be set up to store all documentation and reports, including minutes of meetings and so forth. These will be made available via the Web.

It is assumed that most, if not all, the members of the Project Team will work on one or more work items. If a work item requires more than a small number of people then the project leader will propose, in consultation with the members of the team, one of their number to coordinate the work item. This person would be accountable to the project leader for the responsibilities accepted. Where possible, team members should be accommodated in the same locality.

Progress Reports and Meetings

A meeting schedule for the Steering Group must be agreed. For example, a progress report could be given by the project leader at monthly or eventually quarterly intervals once the project is under way. Plenary meetings of the Project Team will be scheduled to discuss proposals, status reports and conclusions of work items and technical issues.

Initial Milestones

1. During the first phase of the project it will be necessary to set up the Project Team, establish an initial set of work items with their definitions, and refine the operation of the project in collaboration with its members. The first iteration of this work should be completed as soon as possible, but not later than the first quarter of 1998.

2. The experiments to come forward with a motivated set of milestones for the control of each sub-detector. These should include the dates by which decisions must be made on the choice of low-level hardware, buses, etc., plus the requirements for the availability of test software. An overall date must be fixed by which a definitive solution for controls has to be available.

The lists of sub-detector milestones should be established by the end of the first quarter of 1998, and should be updated at regular intervals.

3. Based on the work done in establishing the milestones for sub-detector control, the experiments should also produce a list of short term needs. It is clear that some sub-detectors are more advanced than others and may need interim solutions. The aim is to ensure that any ad hoc solutions adopted can be adapted to the solution finally chosen. In addition, collaboration with sub-detectors and test beams in some cases may allow the testing of possible hardware and software solutions.

The short-term needs should be established by the end of the first quarter on 1998.

4. There is at present under way a Technology Survey and this should report its findings at the latest by the end of the second quarter of 1998. Intermediate reports will be made.

References

1 T. Virdee et al, Draft Report from the Working Group on Common Projects in the Field of Software/Computing and Trigger/DAQ at LHC: Detector Control Systems, December 6^th, 1997.