Lab

Recommended Tools

In addition to the resources that the course provides, students may find it useful to obtain the tools below:

  • wire cutter
  • wire stripper
  • needle nose pliers
  • screwdrivers
  • hex set (ball ends)
  • electrical tape
  • small scissors
  • a small file

Lab Resources

The Srivastava Senior Design Lab (2070 ECEB) is dedicated to ECE 445 usage. This lab provides you access to a vast array of lab equipment, hardware, and software for your use in developing and implementing your senior design project. In addition, course staff will make themselves available in this lab during their office hours to provide guidance on your project throughout the semester. It is our intention that this laboratory space provides you and your team with all the tools you would need to develop and test your project (within reason!). If there is something that you require in the lab to complete your project that does not exist in the lab, talk to your TA and we will see if we can remedy the situation.

Lab Bench Reservations

If and when the semester gets so busy that finding a lab bench to work at becomes difficult, please make use of the Lab Bench Reservation System in PACE. Reserving a lab bench will guarantee priority access to that bench, even when the lab is busy. To use the tool, after authenticating in PACE, you will see a page with a title "Signup for lab bench" with some text and a large table below that. The table shows the schedule for each bench on a given day (use the orange arrows or "Go To Date" text box to see a different day).  You make your reservation by simply clicking in a grid cell in the table, which will turn the box green. Click on it again to un-reserve the bench (and the box will turn white again).  Benches that are already reserved by another group will be denoted with a yellow box (you can hover your mouse over a yellow box to find out what group has reserved the bench).

A few ground rules:

  1. You may use a lab bench (a) during a time for which you have it reserved or (b) any time during which it is not reserved in the system (on a first-come-first-served basis). However, if you are working at a bench that is unreserved and somebody reserves it using the online system, the group with the reservation gets the lab bench.
  2. There is a limit on the amount of time for which you can reserve benches in 2070 ECEB.  The limit is currently a total of 4 hours of total bench time in the lab per group per day (e.g., 2 hours at Bench A and 2 hours at Bench B would max out your team's reservations for the day).  While this may seem restrictive, keep in mind that the course serves more than 60 groups in a typical semester and the lab has only 16 benches.  Also keep in mind that you can work at a bench if it is unreserved.
  3. Some lab benches have specialized equipment at them, such as digital logic analyzers.  Try to reserve the lab bench that has the equipment that you need.
  4. Cancel reservations that you will not need as soon as possible to give other groups a chance to reserve the lab bench.  You can cancel a reservation up to 1 hour before time and not have it count against your daily allotment.
  5. Conflicts and/or reports of people not following these rules should be sent to your TA with the course faculty in copy.
  6. Above all, be courteous.  Especially near the end of the semester, the lab will be full most of the time and stress will abound.  Clean up the lab bench when you are done with it.  Start and end your sessions on time.  Be patient and friendly to your peers and try to resolve conflicts professionally.  If we notice empty lab benches that have been reserved, we will cancel your reservations and limit your ability to reserve lab benches in the future. Similarly, do not reserve more time than you will need.  If we notice that you are frequently canceling reservations, we will limit your ability to reserve lab benches in the future. Finally, do not try to “game” the system and reserve a bench for 30 minutes every hour for eight hours. We will notice this and revoke your ability to reserve a bench.

Lab Rules

There are two overriding rules of working in the Srivastava Senior Design Lab. First, be safe. Second, be courteous. Lab access will be revoked if you fail to complete the required laboratory safety training by the deadline or if you break any of the lab rules. Specific points and examples of what we expect:

Breaking the rules or exhibiting bad laboratory etiquette will lead to a loss of points and/or revocation of laboratory access.

Lab Equipment Rules

Do not remove any equipment from the lab. Students may not change the connections on equipment without TA approval. Any approved changes that are made should be undone before leaving the lab. If a bench instrument is malfunctioning, a red repair tag should be placed on it and you should notify your TA. This alerts the staff to the problem, and allows the Electronics Services Shop to fix the problem.

When using a piece of laboratory equipment for the first time, please ask a TA for help. If you are inexperienced with a piece of hardware, do not assume that it is broken just because you cannot figure out how to use it. Similarly, if you use a piece of equipment to test your project and the equipment does not perform the way you think it should, do not assume the fault is with the equipment, and do not try again with equipment on another bench. Rather, stop and make absolutely sure the problem is not with your connections or project.

If you break any laboratory equipment, you must tell your TA within 1 business day. Any attempts to conceal breakage will result in an F in the course.

Room Access

The lab room (2070 ECEB) is on the electronic key-card system. The Department automatically adds room access to the building and the lab for all students on the roster. You will need a “prox enanabled” I-Card to swipe into the room. If the door does not open after several attempts, you may need to get a replacement card. Room access is automatically restricted to faculty and TAs during official breaks (i.e., Thanksgiving, Christmas, and Spring Break).

Computer Access

The lab computers are EWS computers and are setup like other Windows-based EWS systems you are familiar with. Standard EWS rules apply to these machines. In particular, please store any/all files you generate on a network drive or in the cloud. The C: drive should not be used for any personal material, since it is unprotected and is available only on the particular machine where it was originally stored. A particular computer may be cleared and reconfigured at any time for maintenance reasons.

In addition to the desktop computers, EWS maintains the printer in the lab. You are free to use it to print documents related to your project, but be aware that this printing counts against your standard print quota.

Resonant Cavity Field Profiler

Salaj Ganesh, Max Goin, Furkan Yazici

Resonant Cavity Field Profiler

Featured Project

# Team Members:

- Max Goin (jgoin2)

- Furkan Yazici (fyazici2)

- Salaj Ganesh (salajg2)

# Problem

We are interested in completing the project proposal submitted by Starfire for designing a device to tune Resonant Cavity Particle Accelerators. We are working with Tom Houlahan, the engineer responsible for the project, and have met with him to discuss the project already.

Resonant Cavity Particle Accelerators require fine control and characterization of their electric field to function correctly. This can be accomplished by pulling a metal bead through the cavities displacing empty volume occupied by the field, resulting in measurable changes to its operation. This is typically done manually, which is very time-consuming (can take up to 2 days).

# Solution

We intend on massively speeding up this process by designing an apparatus to automate the process using a microcontroller and stepper motor driver. This device will move the bead through all 4 cavities of the accelerator while simultaneously making measurements to estimate the current field conditions in response to the bead. This will help technicians properly tune the cavities to obtain optimum performance.

# Solution Components

## MCU:

STM32Fxxx (depending on availability)

Supplies drive signals to a stepper motor to step the metal bead through the 4 quadrants of the RF cavity. Controls a front panel to indicate the current state of the system. Communicates to an external computer to allow the user to set operating conditions and to log position and field intensity data for further analysis.

An MCU with a decent onboard ADC and DAC would be preferred to keep design complexity minimum. Otherwise, high MIPS performance isn’t critical.

## Frequency-Lock Circuitry:

Maintains a drive frequency that is equal to the resonant frequency. A series of op-amps will filter and form a control loop from output signals from the RF front end before sampling by the ADCs. 2 Op-Amps will be required for this task with no specific performance requirements.

## AC/DC Conversion & Regulation:

Takes an AC voltage(120V, 60Hz) from the wall and supplies a stable DC voltage to power MCU and motor driver. Ripple output must meet minimum specifications as stated in the selected MCU datasheet.

## Stepper Drive:

IC to control a stepper motor. There are many options available, for example, a Trinamic TMC2100. Any stepper driver with a decent resolution will work just fine. The stepper motor will not experience large loading, so the part choice can be very flexible.

## ADC/DAC:

Samples feedback signals from the RF front end and outputs the digital signal to MCU. This component may also be built into the MCU.

## Front Panel Indicator:

Displays the system's current state, most likely a couple of LEDs indicating progress/completion of tuning.

## USB Interface:

Establishes communication between the MCU and computer. This component may also be built into the MCU.

## Software:

Logs the data gathered by the MCU for future use over the USB connection. The position of the metal ball and phase shift will be recorded for analysis.

## Test Bed:

We will have a small (~ 1 foot) proof of concept accelerator for the purposes of testing. It will be supplied by Starfire with the required hardware for testing. This can be left in the lab for us to use as needed. The final demonstration will be with a full-size accelerator.

# Criterion For Success:

- Demonstrate successful field characterization within the resonant cavities on a full-sized accelerator.

- Data will be logged on a PC for later use.

- Characterization completion will be faster than current methods.

- The device would not need any input from an operator until completion.

Project Videos