Week 3 (9/7-9/13) We have confirmed to work with our client Dr. Keith Hengen. Our project will be to design an electrode manipulator to place an extracellular electrode into a slice of mouse brain tissue to study neural networks. Currently, the experimental setup includes two intracellular electrodes, so we will be creating a custom design to fit the manipulator into the existing experimental setup. We will also be working with a Vamsi Daliparthi, a postdoc researcher who works for Dr. Hengen. Last week, we visited the lab again to get more details on the project and drafted the need statement and project scope. When we went to the lab, we met with Vamsi and talked about design requirements and the current solution they are using. For now, they have a makeshift attachment to one of the intracellular electrode manipulators to adapt it for use with extracellular electrodes. This includes a 3D-printed stabilizing arm to which the silicone electrode is taped. An electronic chip is also attached to this, which has a cord running off of it to transmit the recorded data to a computer. This current solution needs improvement because the chip and cord attachment puts a lot of stress on the attachment, and because our client wishes to have a separate manipulator designed specifically for the extracellular electrode. We talked about other design specifications such as where the new manipulator needs to be placed relative to the other manipulators and the microscope stand, electrical isolation, how the electrode needs to be inserted into the sample, and the movement accuracy the manipulator needs to have. This week, we met with Dr. Klaesner and he helped us edit our need statement, project scope, and design specifications. We took his suggestions and have finished the need statement and project scope. We are waiting to hear back from Vamsi about some of the values for our design specifications. We also got added to the lab's slack channel to make communication easier. Next week we will start reviewing the literature Vamsi sent us and brainstorm design ideas.
Week 4 (9/14-9/20) This week, we reviewed some information that Vamsi sent us to better understand the design specifications. One of the papers he sent described the electrode that will need to be inserted with our manipulator. This paper helped us get a better idea of the type of data that will be collected and the physical characteristics of the electrode. Another thing he sent was a link to a commercial multi-probe micromanipulator system. This system is much more expensive than necessary for our client’s needs and is very useful for us to see as an existing solution. He also sent us a link for the microscope used in the experimental and the bath chamber the sample is placed in. This is useful so we know the exact specifications of this equipment because our design will have to accommodate the equipment and be placed into an existing setup. The microscope will help us view the electrode as we manipulate it into the correct position. The electrode will need to be placed into a sample within the bath chamber so it is good to know what we have to work around. We also started putting together our Gantt chart and website this week. These will be updated periodically throughout as we make progress on our project. Next week, we hope to arrange a time to observe the current system in use while an experiment is being run. This will help us understand the whole process that our client goes through to design something that will be useful for them. We will also start looking into current solutions and brainstorming design ideas.
Week 5 (9/21-9/27) This week, we focused on organizing information for the preliminary report and making a plan for writing it throughout the upcoming week. As a group, we completed a preliminary Gantt Chart that extends through the rest of the semester and includes a few items for next semester (like reports and presentations). This helped us layout a timeline to keep us on track for the next few months, and it will be updated as we add more tasks. It also helped us distribute responsibilities evenly. While creating the Gantt chart, we also decided who will be giving each major presentation. Abby will give the preliminary presentation in October; Maddy will give the progress report presentation in December; Michelle will give the validation & verification presentation in March. We also put together a detailed outline of who would be responsible for writing each portion of the preliminary report that is due next week on October 4th. We will research existing solutions and write that section together. We created the Gantt chart and designated team responsibilities together, but Michelle will be responsible for writing them up. Since we have already compiled information for the background, project scope and need statement, and design specifications/metrics as a group, we divided those sections for the team members to write individually. Below is an outline of how the report sections have been assigned:
Background - Maddy
project scope and need statement – Abby
update based on feedback
metrics – Michelle
communicate with Vamsi
existing solutions – everyone
reading stuff from Vamsi and Molly
look up additional solutions
prelim. design schedule (gantt chart) – Michelle
team responsibilities - Michelle
To make sure we stay on track, we have scheduled meetings and deadlines for the upcoming week. 9/30 8:30-10am @Whitaker- research existing solutions together 10/2 5:30pm @TBD - have drafts of individual writing assignments before meeting, work on existing solutions together 10/3 5:00pm @TBD - synthesize report/put all sections together, start presentation
Week 6 (9/28-10/4) This week, we conducted background research on existing solutions for our project and wrote the preliminary report. We met on Monday 9/30/2019 to start our search for existing solutions and requested price quotes on a few products. We found that the existing solutions fit into one of three categories: mechanically controlled, electrically controlled, or both. Throughout the week, we individually wrote the sections of the report we were assigned. Then we met on Wednesday 10/2/2019 to start writing the existing solutions section of the report. We also proof-read the individual portions and put the pieces together to make the report cohesive. On Thursday 10/3/2019, we met again to finish writing the report, make figures, organize citations, and format it properly. Next week, we will put together our preliminary report presentation. We will meet on Saturday 10/5/2019 to start. Abby will be giving the presentation on Wednesday 10/9/2019.
Week 7 (10/5-10/11) This week, we transferred the information from the preliminary report that we wrote last week into a presentation. We met on 10/5 to compose the presentation. Then we met again on 10/8 to finalize it and help Abby practice. Abby delivered the presentation on Wednesday, October 9. Throughout writing the preliminary report and making the preliminary presentation, we have been able to synthesize all the background information for our project. We have adequately defined our need statement and project scope, determined the necessary design specifications, analysed existing solutions, distributed responsibilities to each team member, and created a preliminary schedule for completing the project. Analyzing existing solutions was especially useful because it gave us a good idea of how this problem has been solved in the past, and we have been able to identify where those solutions have fallen short and what needs to be improved upon them to satisfy the needs of our client. With this knowledge and insights in mind, we plan to move forward with the design process in the coming weeks. Next week, our main goal will be to get our website up and running because it's due date is 10/21. Since we will all be out of town for fall break during the beginning of next week and Maddy will be attending a conference in the end of next week, our next team meeting will not be until 10/22. At this meeting we plan to discuss and brainstorm potential design solutions.
Week 8 (10/12-10/18) Since this week was fall break, and because Maddy was out of town for the rest of the week, there was no team meeting. Michelle and Abby will meet over the weekend to design the website, which is due on Monday 10/21. There will be a team meeting on Tuesday 10/22 to begin brainstorming design solutions.
Week 9 (10/19-10/25) This week, we met up on 10/22 to discuss design ideas. We came up with some initial ideas to secure the electrode to the manipulator arm and came up with some questions for our client. Next week, we will meet with our client about these questions. Before the next time we meet, we will also conduct some outside research about the different types of motors so we can figure out the best type of motor to use for our manipulator. Below are the initial design ideas we came up with: Initial Design ideas for holder
Better 3D printing
Some sort of strap?
Specifically design it for the neuropixels probe
2 connection/secure points
End where shank is
End with control chip
Small box at end for chip & cable
support for flexible cable in middle
Make sure it can easily be connected to data cable
Make sure data cable connection is secure and will not pull it off the arm
Week 10 (10/26-11/1) This week, we met with our client to go over some questions we had about the project. Through this conversation, the scope of the project changed slightly. At first, our client expressed interest in adding a new electrode manipulator to their experimental neural network recording set-up. Since our last meeting, Vamsi has decided that there isn't enough space around the microscope to add another manipulator. There are two manipulators in the current set-up (one on either side of the microscope), and since only one is used for a patch electrode at a time in the experiments, we can use the other manipulator for our project. This makes it easier for our clients because they already know how to operate the manipulator, and it doesn't take up extra space in the already crowded set-up. In this week's meeting, Vamsi also expressed his interest in having us design something that would keep the Neuropixels electrode steady/prevent it from flopping around. This changes our project scope because before, the main design component involved making a new manipulator in its entirety. Now, the main design component will be to stabilize the electrode to prevent damage and increase positioning precision, and to design a way to attach the electrode to the existing manipulator.We also met this week to update our LabArchive notebook according to the instructor's comments.
Week 11 (11/2-11/8) This week, we started planning for the progress report. We met with Professor Klaesner on Monday 11/4 to ask some clarifying questions about what is required for the report and got some advice on how to organize our design ideas for the Pugh chart. On Tuesday 11/5, we met with our client and went into the lab to have another close look at the equipment. On Thursday 11/7, we dove into creating designs and defining what our design criteria will be in the Pugh chart. To start getting ideas down on paper, we each sketched out our own ideas for 15 minutes and then presented them to each other. This was really helpful to see how everyone in the group was thinking about the solution a little bit differently, and then we could all give feedback on the designs together. We decided to break our solution into 5 components: 1. connecting the probe and chip to the headstage 2. keeping the data cable securely out of the way so it does not put too much force on the chip 3. permanent holder to stabilize the Neuropixels probe (this has 3 components) a) connection to the control chips b) stabilizing/holding shape of flexible wire between chip and shank c) stabilizing shank We came up with a couple design ideas for each component and came up with design criteria to rank each design on in the Pugh chart. We also assigned some new team responsibilities for new tasks that have come up as we started creating designs. Abby will be in charge of creating digital drawings for our designs for the report. Michelle is in charge of updating the Gantt chart. Maddy is in charge of creating the Pugh chart. Finally, we created a timeline for the next couple weeks to make sure we will complete the progress report on time.
Present initial design ideas to Vamsi early next week to get feedback
Finalize designs and choose the final design by Monday 11/18
Begin writing report 11/18
Report is due 11/25
Ideally, we will also have the presentation done by then also
Presentation will be at 9:00am on 12/2 in Whitaker 100
Week 12 (11/9-11/15) This week, we focused on expanding our design ideas and evaluating them in a Pugh chart. We have now completed our Pugh chart and selected a design idea to pursue for our prototype. The design idea we have chosen for the permanent holder is to glue a 3D printed support to the Neuropixels electrode that extends from the probe chip, along the flexible wire to the shank. This support will be shaped so that the electrode can easily inserted into the sample. We will make the shank end of the electrode a bright color so that it is easily located. We may also add a retractable cover to protect the shank. The electrode and control chip will be attached to an extension that protrudes from the bottom of the headstage. There will be box on the end of the extension where the electrode will fit, and the box will have a clear lid that flips open and is secured with a latch. We presented these ideas to our client and he is supportive of them and excited to see how it turns out. We also took more measurements for our updated design specifications when we visited the lab this week. We have also started looking into fabrication methods and material prices so we can have a preliminary budget for the progress report. We have started revising our need statement and project scope in accordance with the changes we have made to our project. Finally, we have begun creating digital images of our design ideas to put in the progress report. Next week, we will write the progress report. Hopefully we will have time to make the presentation before Thanksgiving break as well since our presentation will be given right after we come back from break.
Week 13 (11/16-11/22) We spent this week writing the progress report. We worked on individual sections of the report over the weekend, then met on Monday to review each other's work. We also began looking at material prices for the budget on Monday. Then we did more individual work and met again on Wednesday. On Wednesday, we reviewed each other's work again and finished writing the report. Our next meeting will be on Saturday. We will do a final review of the report and make the progress presentation.
Week 16 (1/13-1/17) To start off class this week, we did the yellow sticky note activity to help us plan steps that we need to take to get the project done on time. We plan to have a preliminary design done by the end of this week, then spend 3-4 weeks testing and altering the design until we get it right. By Feb 17, we want to spend have a mostly working design and be done with FDA/safety regulation research. We will be meeting during team time so that we meet twice each week. We will spend one meeting designing and one doing research (and have any extra meetings necessary). Then we will begin writing the V&V report and deciding what our validation/verification criteria are. Following the V&V report and presentation, we will spend about 4 weeks testing the validation/verification criteria. We plan to start writing our final report at the beginning of April, and it is due on April 17. Then we will only have the poster presentation left and will work on that until April 27. Coming back from winter break, we wanted to dive right into product design. We met on Wednesday during team time to start working on CAD designs. We decided to use Autodesk Fusion 360 as our CAD software because it is free for students and can sync online so all group members can access the most current design from their own device. Below is a screenshot of the design we started on on Wednesday. We also met with professor Klaesner for a check-in meeting on Thursday. We discussed the grader's comments on our progress report. We also talked about the most challenging part of our project will be adhering the parts we design to the chip and headstage while also being removeable. We discussed different adhesion options (such as heat-activated epoxies).
Week 17 (1/20-1/24) This week we met on Sunday (1/19) and Tuesday (1/21) to finalize the CAD design that we had started last week. We found similar designs online to get an idea of how to create a hinge so that our prototype could have a hinged top. We also researched hinge pins that would fit the needs of our project and decided on a hinge pin with screw caps originally designed for watches. Once we finalized our design, we created a form file with the bottom of the box and the lid so that it could be printed in our client's lab. On Thursday (1/23) we met with Vamsi to discuss our current design and any potential changes we need to make. He told us that the lab has constructed a makeshift way of using the neuropixels probe to continue conducting experiments while we work on our project. This makeshift design is somewhat similar to our design with a 3D printed box to hold the chip and an extension from the box to secure the probe end. The entire set up is attached with a metal rod to a manual manipulator with x, y, and z-movement. While this setup is technically stable and functional, there are several improvements that Vamsi would like our project to have. First is they would like our design to be able to be attached to both the manual and electrical manipulator so they can use the manual manipulator to initially position the probe, then use the electrical manipulator to more precisely move the probe parallel to the bottom of the holder. They would also like us to design a storage box for the probe. We planned to meet this weekend to adjust our design accordingly. Additionally, Vamsi will be ordering the watch hinges for our prototype and is working on getting us swipe access to the lab so that we can come into the lab as needed. He also recommended using an epoxy to attach our components to the probe.
Week 18 (1/25-1/31) This week, we brainstormed designs to accommodate the updates given to us by our client. When we visited the lab on Wednesday to take measurements for some new parts that need to be incorporated into the design, Dr. Hengen stopped by to check in on our project. He also helped us by explaining how the lab has been arranging the electrode manipulator around the other manipulators. Because they need to use the probe for experiments, they would really benefit from a solution as soon as possible, so we will try to get a working product as soon as possible. A main addition to the design is to incorporate an actuator that will push the electrode forward into the brain sample after it is in position. We need to design a way to connect the actuator to the manipulator and to connect the probe and chip to the end of the actuator. Next week, we will hopefully develop a design and order parts that we need and start printing parts that we made.
Week 19 (2/1-2/7) This week, we created a new design to incorporate the actuator that will push the probe forward into the sample. Our new design includes mounting the actuator and the chip/probe box on a platform that extends off of the manipulator stand. The extension will screw into existing screw holes on the manipulators. The chip box will attach to the actuator via a wheel house chamber. This chamber will be appended onto the box that holds the chip and will have a slot in the back for the actuator to come in. The actuator will be secured to a larger wheel so the wheel will rotate with the actuator and push/pull on the box to move it. Since the actuator is cylindrical, there will be a cradle for it on the extension to keep it in place. To ensure the probe moves smoothly and in a straight line without falling off the extension, the extension will include a rail for it to slide along. We created CAD drawings of the updated chip box and new extension piece. Vamsi printed the chip box this week, but the extension was too large to fit in the 3D printer in one piece, so we had to alter the design. Instead of printing a single piece, we will cut the base of the extension out of plexiglass with the client's laser cutter and 3D print the actuator cradle and slider rail. Then the cradle and rail can be glued on top of the base. Finally, we started brainstorming V&V criteria this week. We are having some trouble deciding if some criteria fit within validation or verification, and have some other questions about writing the V&V report, so we will meet with Professor Klaesner on Thursday next week to get help from him.
Week 20 (2/8-2/14) This week, we did a lot of research into what sort of regulations are placed on the product we are making, and completed 3D printing the parts for the first iteration of our prototype. We have concluded that out electrode holder would not be regulated by the FDA or the USDA because our client won't be using it for any in vivo studies. The prototype looks promising so far. The fit for the screw holes on the extension was not quite right, but with some filing, they fit well enough to attach onto the manipulators. The rail for the chip box to slide on was not a perfect fit either, but filing both got it to fit well enough for initial testing. The other parts fit pretty well. In the next iteration, we will adjust the sizes of the screw holes and rails to alleviate the fit problems. Soon, Vamsi will get the chip out of the box that they made (it is currently glued in) so that we can test the fit of our box. This weekend, we will meet up to get keep working with the prototype. We want to test the movement of the chip with the manipulator and actuator and make sure we can easily position the probe in the sample area. We are concerned that the box may be a little too big to easily fit in the sample area, so our next iteration will probably include shortening the probe box and removing the lid. We also met with Professor Klaesner this week to ask some questions about the V&V report. Specifically, we wanted to talk about how much of the design changes needed to be included and get some advice on how to test some of our verification criteria. Next week, we will test things out on the prototype to see what works, what doesn't, and what needs to be improved. Hopefully we will know what adjustments to make and will have designed the second iteration. We will also try to design a new clamp/handle for the slider on the manipulator since the one that it came with doesn't fit. Finally, we will do more work with defining our V&V criteria and devising test methods.
Week 21 (2/15-2/21) This week, we spent most of our time writing the Verification and Validation (v&v) Report. On Monday, we discussed our v&v criteria and ways to test those criteria. On Wednesday, we started writing the report and assigned each group member a portion of writing to do over the weekend. By next Monday, we plan to have most of the report written, and spend Monday revising the report and getting pictures of the prototype for the report. On Tuesday, we worked in the lab. We checked to make sure the actuator could slide the chip box back and forth along the rail. We also placed the manipulator and extension in the Faraday cage to see how well it fit into the experimental setup. We determined that the end of the extension is too bulky. To make it smaller, we will make the chip box shorter and remove the lid. Additionally, the extension itself is too thick to be close to the sample area. The design will need to be adjusted so that the chip box can protrude past the end of the extension.
Week 22 (2/22-2/28) This week, we did not make any progress with our prototype because we spent the week writing the V&V report and making the V&V presentation. We also learned this week that Vamsi will no longer be our main point of contact for the project. Instead, Dr. Hengen will be step in to help keep the project on track. We are planning to meet with Dr. Hengen next week to discuss the logistics of this and update him on the current status of the prototype.
Week 23 (2/29-3/6) This week, we didn't have a lot of time to work on the prototype because we had to go to class to watch and give our V&V presentation. However, on Tuesday, we met with Dr. Hengen to talk about moving the project forward since Vamsi is not mentoring us anymore. We will be looking into other potential solutions for translating the rotational motion of the horizontal actuator into linear motion. We reached out to NewPort to ask if they have any suggestions, and they will get back to us soon. We will also search around for other solutions such as stepper motors. In parallel with this, we will continue to refine our wheel house design in case it ends up being the best option. We also went into lab on Thursday to start working on the probe support. We tried shaping a wire and tacking the probe on and experimented with different angles and positions. We made some progress, but want to talk with a lab member who has run the experiment before to get their take on the best angle and position.
Week 25 (3/14-3/20) This week, we came up with a plan on how to continue our project without meeting in person or going to campus. Our client is Keith Hengen, who has a lab in the biology department at WashU. We have not spoken to our client directly yet, but he has sent us a lab email explaining that the lab is transitioning to a minimal operation phase, during which all nonessential tasks will be performed remotely for at least 2 weeks (and up to 2 months). We are also emailing him our plan for the rest of the semester to start a dialogue about what his thoughts on the matter are and will keep you updated if he has different suggestions than we have already come up with. Because our project depends on us being in lab to create and test the prototype with the client’s experimental setup, we don’t think that it is plausible to deliver a finished product. However, we want to make sure that our client can continue the project and complete it in the future. We would like to prepare a proposal report for our client on how to complete the project in our absence. We will compile all the information we have gathered about potential solutions and all the designs we have created. We will also continue to update our design and provide instructions on how to construct and test the design we come up with. We have asked for our client’s input to see if he has any suggestions for what else we could do to make any more progress on the project remotely, and if you have any other thoughts, we are open to any suggestions. It may even be beneficial to schedule virtual meetings with each group to discuss how to move forward. Another goal we set this week is to have our LabArchive notebook fully updated by 3/27.
Week 26 (3/21-3/27) This week, we have updated all of our lab archives notes. We weren’t sure what to include for in the IP Information folder or the V&V Proof of Concept folder, so we will ask Prof. Klaesner about those next week. We are meeting again today (after this report is due) to make a game plan for next week. In general, we will probably talk about updates we will make to the design and what we will include in our report. Our client Dr. Hengen is on board with our plan to write a report, and we will continue to keep him updated.
Week 27 (3/28-4/3) This week, we met on Monday and Wednesday to discuss our final design that we will write about in our report and give to Dr. Hengen. We've made adjustments based on what didn't work about our original prototype that we were working with before spring break. Mainly, we are redesigning to make the profile smaller and changing the rail system on the extension. We are currently designing it for the actuator that we were using before, but we had discussed potentially changing which actuator we use, so we will update the design for the new actuator in case Dr. Hengen decides to get the new actuator. This requires updating a lot of dimensions, and we will continue parsing out what those dimensions should be on Friday. By next week, we plan to have the final design finished. Next week, we will create the final design CAD files and start writing the final report. Below is a picture of some sketches that we have made so far.
Week 28 (4/4-4/10) This week, we finished redesigning the chip box and rails. We created CAD designs of these new parts, which we will send on to our client so they can continue the project later. We have kept a list of measurements that the client should double check before printing the new parts since we couldn't check them ourselves. We also started working on the final paper this week. We've realized that some of the items we had in our list of design specifications were basically just measurements we took that didn't affect the design much. We adjusted our design spec list based on this and then went through the list to determine which specifications we were able to meet and which ones we didn't meet. We will meet again on Friday afternoon. By then, we should have the design specifications fully updated, a complete parts list, and the project overview written. Then we will continue to work on the paper. Since the paper and video are both due on April 20, we plan to have the paper done by April 17 so that we can have a few days to just work on the video.