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This is where all of our weekly progress will be recorded
Monday 01/04.24 Easter Holiday Tuesday 02/04.24 Today was used to swap from the chinese circuit board to the GRBL. In addition, a new iteration for the camera calibration was made, as well as a new iteration to the attachement plate. The sensors were also installed properly into the freezer.Wednesday 03/03.24 Thursday 04/04.24 Friday 05/04.24 Monday 25/03.24 Peter had a complete makeover of the cable system of the CNC. In addition, a box with all the wires was added to the side of the freezer to make it look cleaner. Tuesday 26/03.24 Worked on the tightner for the iris clamping mechanism. Wednesday 27/03.24 Continued work on the clamping mechanism. Also installed light into the freezer, although this is not permanently mounted. Will need to find the best position for the LED-strip before mounting it permanently. Also swapped from the chinese motherboard to the GRBL motherboard. Thursday 27/03.24 Easter Holiday Friday 29/03.24 Easter Holiday Monday 18/03.24 Today was master scrum and we got input on how the work was going and what to focus on going forward. Therefore, going forward Peter will focus on the development of the CNC in the freezer, and Øystein will focus more on the innovation of clamping mechanisms. They don't have to be fully functional, but tested well enough for us to be able to provide some recommendations for future work. There is still no update from St.Olavs regarding the prostate cutting. The day was spent making the final adjustments to the freezer (with regards to the door and the wires) for it to be ready for testing. Tuesday 19/03.24 We figured out what the issue with the CNC controller was. It turns out our controller is not a GRBL 1.1e or earlier, it is a MKS DLC32, that uses GRBL 1.1h, but there is something wrong with the current MKS DLC32 firmware that causes it to ot be able to interpret M4 (spindle on with variable speed) commands. We have found the resources that explain the issue and we have found the necessary firmware upgrade, but the firmware uploader for that board does not want to cooperate with my computer. In addition, we are afraid that if we upload new firmware, and something goes wrong, we wont be able to do testing until we get a replacement. The resources can be found here: https://github.com/makerbase-mks/MKS-DLC32/blob/main/MKS-DLC32-main/firmware/readme.md https://forum.lightburnsoftware.com/t/dlc32-m4-does-not-work/67127/6 https://forum.lightburnsoftware.com/t/mks-dlc32-device/99971/5 Further development of a possible iris clamping mechanism. Wednesday 20/03.24 We decided to buy ourselves a GRBL. It is more familiar and it is smart to have a backup. Preliminary testing was conducted and results can be found here. Thursday 21/03.24 Friday 22/03.24 We now have a working iris mechanism clamper who nicely forms around the MDF-prostate. The focus has now shifted towards securing the pins in place. First to be tested will be another cam-shaft mechanism. Monday 11/03.24 Made an iris closing mechanism to research pottential gripping methods. Will be pursuided further. Also started seting up Lightburn for the CNC and playing around with the software. Will make all the eletrical wires run out of the freezer so that we can close it and propperly begin testing by wednesday.Tuesday 12/03.24 Today we made a temperature sensor array using an arduino uno with an ethernet shield and a SD-card. It will read the temperature from the 3 sensors and write it to file, so that it can be plotted by the python code on the SD-card afterwards. Additionally, after some hassle, the CNC now communicated correctly with lightburn. It was struggling with understanding the M4 commando (turning on the spindle), so we had to change the device board in the Lightburn settings.
Now the CNC functions as it should. Wednesday 13/03.24 Made a new attachement plate with a cable slot for the camera to be mounted Thursday 14/03.24 Today, the Lightburn programme was completed. In addition, the camera was mounted to the CNC. We found that a 90 degree USB-C adapter was needed to get a sufficient cable arrangement. This was therefore requested to be ordered. Lastly, we made a "pepperkake-form" of a prostate to easier be able to cut out ham slices more uniformly, and in the shape of a "prostate". Friday 15/03.24 Today we prepped the ham for testing and upgraded our MDF base plate for an aluminum base plate. Monday 04/03.24 Made a small 3D-printed version of some fractal vise clamps. Demonstrated them on the Scrum.Tuesday 05/03.24 Made a camera mount and a square clamping frame.Wednesday 06/03.24 Øystein was sick today. Thursday 07/03.24 Peter was on winter holiday. Øystein made an arduino setup for 3 temperature sensors. Friday 08/03.24 Today, an attempt was made connecting the arduino directly to a CSV-file via python, but there was alot of problems with VSCode. Therefore, time was spent managing the cables for the CNC. Monday 26/02.24 Scrum with Martin and rest of Trolls today. Made support beams for the Z-axis frame. Continued development of the clamping prototype. Electronics were connected to the controller. Tuesday 27/02.24 Mounted the Z-axis assembly to the CNC today. Also got vaccinated. Continued development of the clamping prototype. Wednesday 28/02.24 Mounted the Z-axis assembly using the proper ordered t-slots and brackets. Found out that the support beams were an overkill as the brackets made the Z-axis assembly stable without the support beams mounted. Therefore, they are dropped from the CNC for now. Thursday 29/02.24 We have begun discussing how high the clamping frame should be mounted and if some rollers should be included to reduce torque strain on the clamping attachment. A camera mount is also in production. Friday 01/03.24 Today we have continued development of the prototype. The clamping attachment finally fits right and we could get hands on experience with how the concept fits on the CNC bed. Monday 19/02.24 Today we finished measuring the x and y axes and cut them, along with their lead screws. They all fit nicely in the freezer. We started by very precisely measuring the cutting-line. Then we brought the profiles and screws down to the workshop and got them cut. The new profiles were prepared by filing down sharp edges and threading new M5x0.8 holes.
Insert Images Tomorrow we will finish the installation of the CNC while simultaneously thinking of how to install a stable z-axis and a well functioning clamping method. Tuesday 20/02.24 Today we started with improving the CNC. We worked on the clamping mechanism We also added a base board for extra stability and a more professional look. The plate is saved as BunnplateCNC.dxf. The first iteration was made using 6mm MDF, to check if the measurements fit. Tomorrow, this will be made using 3 or 4 mm aluminium and a platecutter. To increase the stability and the friction against the freezer we mounted the legs that came with the CNC. They were mounted on top of the base plate using M5x25 screws. This would ensure stability, but would not collide with the wheels rolling through the profiles. Wednesday 21/02.24 Today, the old MDF baseplate was replaced with a new baseplate in 5mm aluminium. In addition, the rear supporting beam was mounted to the CNC. The spindle motor was also mounted on the Z-axis setup, and work began planning where the Z-axis will be mounted to the CNC. Also, the clamping mechanism was also improved further. Thursday 22/02.24 Made the Z-axis support beam and pillars. Not mounted to the CNC yet. We explored what requirements our camera should have. Friday 23/02.24 After some practical testing and some makeshift Lightburn calibration, we found that further camera-and-clamping work should not be conducted until the CNC is operational, as this will provide valuable insight. The Z-axis has been mounted to the frame. It will be mounted to the CNC as soon as the T-slots and brackets from RS arrives. Monday 12/02.24 Today, during the scrum session, it came forward that more time should be spent discovering different gripping mechanisms instead of only focusing on improving the existing gripping/clamping setup at MRCL. Therefore, we are going to use this week while we wait for the CNC to arrive on exploring clamping yet again. Some molds for silicone clamping has been printed, and will be made ready tomorrow. Tuesday 13/02.24 Today, silicone was poured into the clamping pin molds. They will be cured by tomorrow and be ready for small scale testing. Also, Peter started on a design for a 6-clamp solution inside Fusion360. This design will be further improved once the CNC has arrived, and we know more about how we want to implement our clamping solution to the CNC. Wednesday 14/02.24 Today, the silicone clamping pins were tested. How that went is described closer here. In addition, some more silicone clamping pins were made, with a harder silicone. Thursday 15/02.24 Today the CNC we had ordered arrived! We therefore have started planning on how to cut the frame so it fits inside the freezer. In addition, the second iteration of the silicone clamping pins were tested. How that went is described here. Friday 16/02.24 Monday 05/02.24 We finished the testing the performance of the CNC and it's electronic components after long time exposure to a cold environment. We left the freezer on for around 1 week, at around -18 degrees Celsius. The conclusion from this experiment was that the electronics still functioned as intended after being frozen for 1 week. However, there were some sqealing from the lead screws, which could be solved using a lubricant ment for cold environments. In addition, we have started planning the milling locations for the prostate. but untill we know how large the prostate slice is, this is going to be put on hold. Tuesday 06/02.24 Today the freezer arrived and so the design for the final product began. Information about the freezer has been stored here. The rough plan for the design is something like this:
Wednesday 07/02.24 Today we ordered the CNC. The rest of the day was spent researching other necessary components for the final product. Øystein looked into cam levers and cameras, while Peter explored the temperature sensor array. Thursday 08/02.24 This day was used to read through some HardwareX-articles. Friday 09/02.24 Waiting for the CNC, we have moved our attention to writing. Monday 29/01.24 We had a little start up meeting with Håvard. Together we came up with an idea of how to make drilling a prostate work. We also laid a plan for testing popping extraction one more time, this time at even colder temperatures and with less temperature fluctuations during milling. This is described in Prostate Extraction under test 2. Tuesday 30/01.24 The main plan for today is to have a discussion with Sebastian about the way forward, and then execute popping extraction test 2 and begin preparations for popping extraction test 3. The MR Core Labs team requested a statement regarding the projects progress so far and its state at this time, as well as a rough weekly plan so that they can better plan ahead. This plan can be found here. We also tested the popping extraction method with the samples being left in the freezer overnight, before being put into a box filled with dry ice, with a temp of around -100*C. The tests resulted in the slice shattering into pieces, with the samples also shattering. Images can be found here Therefore, another slice will be milled, and extraction at a lower temperature will be performed tomorrow. Wednesday 31/01.24 Today we conducted extraction popping test 3 and got good results. Many samples were extracted without harm to the slice or sample. The best success rate was achieved when we used a scalpel to further weaken the bond between slice and sample. With this we now have a complete overview of what benefits and disadvantages comes with vacuum gripping. After consideration we have chosen to pivot from the vacuum gripping solution and instead incorporate a solution more similar to the one currently in use at MR Core Labs, only automatic. Even though the vacuum gripping with popping extraction would be possible to perform, we feel that the concept bring too many extra components and therefore possible complications to the product. In addition we believe that we can guarantee a higher success rate, less workload for the operator, and a less complicated product to learn/operate with normal clamping. We will still perform a test tomorrow regarding the effect of spooning on the extraction of the slice. Going forwards we want to start creating rough designs of how we envision the final product to look/work, as well as incorporating any components necessary for prostate milling into the ARTS 1.0. Thursday 01/02.24 Today we performed popping extraction test 4. This is further described here. We began creating the design for the new gripping solution. This is further described here. We started making the base-box that we need for the prostate cutting. This is further described here. Finally we have started making an outline of our thesis. Friday 02/02.24 The base box for prostate cutting was improved further today. Read about it here. Monday 22/01.24 Peter was sick today, and Øystein had to do some vaccination. Therefore, no work was done today. Tuesday 23/01.24 Wednesday 24/01.24 Today we decided to split up to increase productivity. Øystein is going to focus on finding a CNC and testing the filters with different pump. Peter will test the popping extraction method and research if there is a freezer we can modify. We have both began doubting the vacuum gripping solution. We have concluded that the problems it introduces were not as simple as first though. It does provide an optimal non-invasive gripper and makes it possible to mill several samples on the same procedure, but it bring the requirement of another cooling method, a filter, and a new extraction method. We have decided that if the popping extraction works and if we find a filter that works we will have to make an overall assessment on whether we feel it is worth continuing with or not. The first part of Peters task is complete. Samples are cut in turkey slices and are placed in the freezer to freeze. I had to calibrate the equipment to be sure to not crash into the base plate while milling. The depths i measured was: Thursday 25/01.24 The vacuum tight acryllic box was tested at St.Olavs today. The vacuum pump there was able to draw around 96 l/min. of air through the box. The ham slices tested were heldt firmly in place when all the holes were covered, even with the filter in place. It lost a lot of effect when half of the holes were left exposed. In conclusion, the vacuum clamping will work, when everything is made to be completely vacuum-tight. In addition, if the "base box" is made from stainless steel, it can be machined to be vacuum tight to a lid via an o-ring. It will also be able to be sanitized. We are also allowed to request to borrow the vacuum pump for some days, but this has to be agreed with with Sebastian. Friday 26/01.24 Today we have continued to research freezers. we found one at elkjøp that is more powerful than the one we found at power. It was difficult to deduct from the images whether or not it has the desired qualities, so we will have to go to the store and inspect it. We have also tested and evaluated the popping method. It is described here. The conclusion was that it failed. Monday 15/01.24 We started the semester with a meeting with Håvard and then a meeting with Martin. We have outlined a plan for the semester. We aim to drill a prostate within two weeks. This part of the project is recorded here. The next step will be improving the sanitation. Tuesday 16/01.24 Today we have researched ways to implement a filter on the suction, as we believe this will be the most effective way of stopping contamination. We went down to the MR Core Labs and discussed with Sebastian what type of filter was standard in cases like this. It is discussed here. He also proposed that we do not spend time disassembling the last prototype, but rather buy new parts for the new prototype as this will both save time, but will also leave us with a functioning prototype that we can use for testing and comparison. The results from our first day of filter testing was not good. The filter we got to test from Sebastian almost shut down air flow. Combining this problem with the added complexity the cold removal from the vacuum system, and the still unsolved extraction method, does not bode well for vacuum suction. Even though these hinderances are slowing the prostate drilling test down, it is a product problem we would've had to meet sometime, so its better to face them now, early on, rather than later. Tomorrow we will have to keep exploring ways to solve this issue. Wednesday 17/01.24 We have landed on trying a HEPA filter for our solution. We will need to decide what size we need, we should probably aim for maximum air flow and pressure, and optimize later if needed. The Vacushield will also have to be tested with a vacuum pump located at MR Core Labs. If the clamping works with that pump and filter combination that would be great. We have also started evaluating possible ways to improve the prototype in the coming months. Thursday 18/01.24 The air flow through the tube connected to the vacuum cleaner was measured to be around 100L/min (v=21m/s, d= 10mm). Based on this number, we decided to order the biggest HEPA-filter available, just to be safe. In addition, a box made from 6mm acryllic has been made for testing the vacuum pump down at St.Olavs. Work will continue on this tomorrow. Friday 19/01.24 The Vacuum tight acryllic box was completed today. Holes were drilled into a baseplate made from 3mm aluminium, which then was mounted to the acryllic box using Tec-7 sealant. Everything was then clamped, and will be left over the weekend to dry. It will hopefully be fully sealed, adn ready to be tested next week We are now done testing and very busy writing the thesis Monday 20/11.23 Today was a very productive day
We concluded to buy the new vacuum and just give it back if it doesn't work. We continued the testing of the flowrate while we tested the cooling of the system. By measuring the overflow of air, we can see how the vacuum performs while fully connected.
We updated the risk assessment to account for dry ice. We made preparations for the test tomorrow described in the setup section in Final Testing. We tested our hope from Friday, that our vacuum would keep the temperature stable. The temperature started out at -23.4
This is in no way optimal, but in every way good enough in terms of tissue integrity. Tuesday 21/11.23
Wednesday 22/11.23 Today we went to Nortura and collected the organs. We spent the day cutting them up and taking pictures of them to store their sample id digitally. Thursday 23/11.23 Today we performed the testing for this project. It was a very valuable experience that gave us a lot of insight into our prototype. It is all described in Final Testing. The testing took A LOT longer than expected. This was due to the many errors and complications that arouse. This did however provide an us with the opportunity to fix it and immediately see results. We quickly experienced one of the downsides of our vacuum solution. It makes a lot of noise. And it also draws some air from its surrounding, which introduced moisture to our tubes and caused it to clog inside the styrofoam box. The moisture did however provide some valuable information. It allowed us to see where the air flowed. image Due to the third kidney slice being relatively thawed we became curious to whether the temperature sensor was right, so we check with an infrared thermometer, which said the plate was 0*. This definitely needs some looking into later. Friday 24/11.23 Today we finished our testing. One noticeable detail was the amount of spooning that stayed stuck to the mill above drilling height. Could be worth remembering for further work. Monday 13/11.23 We started the day by going to St. Olavs and retrieving a styrofoam box and some dry ice. The rest of the day was spent implementing and testing the cooling method. This is described on the Cooling page. We also made a new metal bed by drilling through the holes in our MDF plate, so that the machine will be ready for testing once the cooling method works.
Next we want to repeat the test, but with a full box of dry ice, instead of one that is 1/3 full. Wednesday 15/11.23 Today we continued our experiment with a full box of dry ice. First we turned on the vacuum, sucking air out of the box. What we saw was that our new seal was not air tight enough and air was leaking out through the lid. This reinforces the known issue of trying to vacuum seal something that was not meant to be airtight. We then went back to the idea of pumping air in through the tube, instead of sucking it in due to vacuum. We used the small 120W hand-pump to pump air through our pipe. We used an infrared thermometer to measure the temperature of the air going into the box. It was -20*C. The air going out of the handpump, going into the tubing system, was significantly hotter than the environmental air, and even the air going out of our big 1000W vacuum. Due to this we decided to create a makeshift heat exchanger by threading an outgoing tube through the ingoing tube of the vacuum. CADs were made at the end of the day and set to print to Thursday. Thursday 16/11.23 Today we tested our heat exchanger vacuum adapters. They seem to be looking okay, but some of the dimensions are a bit off. We quickly update the designs and set new prints to be done after lunch.
I had a productive talk with Henrik Øverbø about our cooling system and the possibilities of optimalization. Short summary: - Creating a small closed loop would be more optimal. Longer tubes = less efficient. - Read Henriks master, could provide valuable knowledge. Friday 17/11.23 Today, we started with a scrum session where Peter, Håvard and Eirik were present
We alse ran some test with the completed heat exchanger setup. We mounted the tube into the vacuum hose and cut the pipes to size. We have made a cooler spiral from plastic tubes with a wider diameter (Ø9mm) so that more air can be pushed into the freezer. After refilling the isopor box with dry ice, we gave the system some tests. In the first test we started at 1,9 degrees and the pump pulled it down to -2,3 degrees and stayed there. In the second test we had let the freezer cool to -4 degrees and is stayed there for 90 sec, and then we turned the vacuum of. We also have started ordering organs from Nortura to prepare them for slicing next week. Monday 6/11.23 Today we quickly explored the possibility that the vacuum pump was too weak. We redid the test with a more advanced vacuum pump. This did, not surprisingly, result in better and tighter grip. We were thus able to reduce the O-ring size, which was a requirement for continuing the exploring.
However the force proved to be too much for the ham-slice. The slice quickly gave in to the force of the pump.
Considering that a prostate is approximately double the thickness and will be continuously cooled to -20 degrees, so it MAY work, but we have doubts. We await more testing till after prostate drilling. Later that day we researched freezers, since the freezer at the lab is broken. We wanted to see if we could combine the need for a freezer now with the vision of a standing freezer for our machine after new years. In preparation we made a box in mdf that would illustrate the size of our CNC-machine, so that we could easily test if it would fit. We went down to Skousen because very few images online showed whether or not the shelfs were removable. We found out that they are not. No freezer of our required size had removable shelfs. Not at Skousen, not anywhere. We discussed possible solutions with the person in the store and almost everything failed. - Bend the cooling on the shelfs to remove the shelfs: No pipes bursts - Remove the shelfs: No, gas leaks - Modify a fridge to be colder: No, Too difficult We ended at a possible solution: - Modify a box-freezer. Cut out the front and place metal in the bottom to increase cold-capacity.
There is supposedly not cooling wires in the walls of the box freezer, but we are skeptical. Next time we are at Skousen, we ask to plug it in to see where the frost gathers. If we see no sign of cooling wires, we can go to Elkjøp and ask to get one of their broken freezers to cut to pieces and see how it is built. Friday 10/11.23 Our plan for Friday will be turning on our machine and seeing how it functions at its current state. While it cools we will work on solving the problem of adding cool air to counteract the temperature increase when sucking out air. We turned on the machine to have it start cooling itself while we worked on finishing the other parts of the machine. We then went on to calibrate the camera and craft a aluminium bed-lid while discussing how we wanted to cool the air going into the box. While doing that we researched vacuums that were more compact than the one we currently use. We found that our current vacuum has a volumetric flow of 4000 l/min as max, although we believe our flow to be less as the tube-volume is significantly less going out of the box, than into the vacuum.
This was the best handheld vacuum we could find that had a described volumetric flow.
We also found this which had a higher max power output (watt), but hadn't described its volumetric flow.
We concluded with leaving this be for the time being and focusing on just making this work using our current vacuum, as it had an output. We then worked on implementing our design described here. Monday 30/10.23 Today both of us were busy doing other course work Friday 3/11.23 We decided to test the O-ring using a handheld vacuum pump instead of the vacuum we used for our "air-hockey" bed. The reasoning behind using an O-ring was to create an air-tight seal and thus not needing to draw large continuous streams of air. First we tried using it on the MDF plate (iteration 9) and this didn't work. We saw this was due to the fact that MDF is not air-tight. We fact-checked this by trying to vacuum grip a MEF plate without the silicon protection we have on our plate, and it wasn't able to maintain a pressure.  
We then quickly crafted a makeshift bed out of metal, as metal is air-tight, and drilled a hole.
This was tested on many different materials and with many different size O-rings, and the conclusion was that we had to have quite a large O-ring for it to have any effect.
We then moved on to testing on our frozen ham slices and this did not give good results. On the smaller O-ring, the pump did not manage to grip at all. On the larger O-ring, which is already borderline too big, it managed to grip after pumping for quite some time, and the it deformed the slice, by dragging it down.
There are several reasons why it didn't work. The O-ring could be of the wrong type. The pump could be too weak. Monday 23/10.23 Since last Friday's test had to be done without ham, we redid the test today, but this time with ham. We bought some ham from the store and froze it down while squeezed flat as this would make it most resemble the actual prostates. We developed a new bed lid to test friction. The new bed with metal holes had a little bit more friction. While testing we also discovered a small air-leak between the old bed lid and the rest of the bed. This means that we should be able to grip a little bit harder with a completely air-tight setup. Solving this may be as easy as adding more magnets.
We also designed an adapter for attaching the vacuum to our tube.
The testStarting the machine: The machine took 2 hours to reach -12°C Attaching the computer: We had zero complications. Starting the software: We had zero complications. No calibration had to be done. Inserting the slice: The insertion of the slice was somewhat difficult, but we had no complications. Cutting: The cutting went well. It was performed at ~-10°C. The slice was held perfectly still. There was however the problem of spooning, which we know is worse at higher degrees. We also suspect that the drill may have been a little bit dirty, which worsened the quality of the cut.
We then tried to pop out the sample, like you are supposed to do after drilling. This went medium well. A little bit more meat was torn off, so we need to decrease the remaining thickness(drill deeper)
Retrieving the slice: The retrieval of the slice went well. The plate was somewhat stuck, but with some patience it went well. Conclusion: The vacuum solution is strong enough to keep a frozen slice of meat fastened to the drill-bed. Comments: The vacuum pulled a lot of cold out of the freezer. During the procedure the temperature rose from -10°C to -3°C. We can solve this by simply pumping the air back into the freezer. The spooning gathered around the cut, which reduced visibility, but had no impact on the quality of the cut. By sending the video feed to our other pc we managed to get a better view of the drilling during the procedure.
Friday 28/10.23 Today we first had a meeting with our counselor and then with the ARTS team at St.Olavs. In our first meeting we talked a little bit about our progress and the way forward. Getting answers to the questions we had after these first two months with work. We concluded that we have approximately 4-5 weeks left until we need to start writing our project thesis. Going forward we want to focus on improving the gripping method as that is the part of our POC that needs most work. Håvard had a good idea of using a single hole in our drill-bed and have it sealed with an o-ring. The upside of this is that the seal between the ham and the vacuum would be tighter, thus increasing the gripping force. As no spooning can escape down into the vacuum, no filter solution would be needed. In addition there would be less leakage of cold air, removing the need for an active cooling method during drilling. The downside of this is that the area covered by the o-ring would then be unavailable for drilling. However if this area is small enough, then if wont be that much of an obstruction.
Håvard also advised us to look at his master thesis to se how a master thesis is structured, so that we know more about how we should think when structuring our thesis. We have also scheduled a meeting next week where we will get to learn about zotero, which will come in handy when writing our project thesis. The feedback we got from our ARTS meeting was that they really liked what they saw, but would like to see it done on objects that have properties similar to that of a frozen prostate, only of worse quality. Thus testing the edge cases and further proving that it will work on real prostates. Examples of this could be:
Monday 16/10.23 After testing the 7th iteration vacuum gripper it was decided that it was risky. There was noticeably less suction with that tube. In addition the notch margin of 0.15 mm was too small. The day was therefore spent testing what the margin should be and looking for better tubes. We believe the last margin test failed due to the test-prints being to narrow. This time we instead printed the whole width. 6 variations were printed, ranging from 0.20mm to 0.45mm, with a 0.05mm interval. After testing these against our bed lid we found that 0.45mm would probably be the easiest to use while still not so loose that the seal is broken. In addition we found a tube that was flexible enough that had an internal diameter of 11mm. Next time our bed hopefully functions properly and we can assemble the whole machine and test it. Friday 20/10.23 We realized today that we might have prioritized wring the last 2 weeks. A better way of testing the vacuum would have been creating a bed with the largest possible tube and trying to drill, and then reducing the tube size for practical reasons, while maintaining the gripping ability. The drill and bed was assembled and the suction seems to work well enough for our purpose. Then we calibrated the drill to the achieve the correct drill height and and refined the workspace area, so that the drill wont accidentally cut into the metal frame.
Next we accessed the camera and calibrated it to the bed. It took several tries and small adjustments to make this accurate. Now we have created an alignment method described here.
To our surprise there were no frozen chicken slices in the fridge so we had to resort to testing with a chicken slice. In the first test the vacuum gripping was not strong enough. It could be caused by several things; too little airflow, a too hard test-material, too low-friction bed-lid, or increased shear forces due to the crooked spindle. We then hooked the vacuum tube to the lab-vacuum and it worked perfectly.
Monday 09/10.23 Today the newly printed beds were used to test how big diameter we need in order to have a high enough airflow through the bed. The test is elaborated here. The results showed promise and a need to test further with smaller diameters. This will be conducted later this week. Friday 13/10.23 The print we put on on Monday was not to be found when we returned today. This was too bad as it forces us to delay the testing to Monday. Instead we spent the day preparing for the assembly of the complete prototype on Monday, as well as refining the design of the bed to better fit in the machine. We have also searched the Composite lab for tubes with internal diameters we know work in case Monday's test fails, so that we have a bigger chance of making a working prototype on Monday. We found one promising tube with internal diameter of 6mm, and external diameter of 9mm. Last test we had to file the gap where the bed top would sit, because the margins were too small. These margins were tested today by 3dprinting and measuring, and correcting the cad if it is too tight or loose. After testing with 3 different prototypes we have concluded that a margin of 0.15 mm is good for a tight, but not too tight fit. The latest design is being printed to next time. Then we will test if the suction is sufficient, and if it is we will assemble all the parts of the machine and test it. Monday 02/10.23 Today, we worked on implementing a vacuum gripper on the CNC-machine. We made several small prototypes from lasercut MDF, and tried to find a good way to include a vacuum tube from one of the sides. We will continue to work on this on wednesday.
Wednesday 04/10.23 Today we worked on improving the vacuum attachment to the drill-bed. We did at last find a design we though would work well. We decided to combine the entire drill-bed design into one piece and 3D print it.
Friday 06/10.23 Our next task will be to find out where the tubing for the vacuum will go. One way is to drill through the bottom or preferably into the bottom and out the side. In addition we need to find a way to pump the same air back into the box as to not remove all the cold air from the box. Before we drill and wire the tubing, we need to figure out how big of a tube we need. We have started manufacturing several beds with different vacuum-hole diameters, so that we can test it on monday. This will hopefully lead to us testing the complete setup at the end of next week. Monday 25/09.23 Today we started developing the first vacuum gripper prototype. We tested it both at TrollLabs and down at MR-lab At the end of the day we had a meeting with the people responsible for the hyperspectral imaging part of the project Friday 29/09.23 Today, we started with a scrum meeting. Participents were Peter, Øystein, Håvard & Eirik We developed a quick version of the cam clamp holder, before taking it down to St. Olavs for testing together with the vacuum gripper made on monday. How the test went you can see here: Clamping test 1 (29.09.23). We will now focus on getting a vacuum gripper on the CNC drill in the freezer. This will be the focus point on monday next week. Monday 18/09.23 Today we worked out a way for the drill to start spinning before lowering itself onto the slice. The solution was to include a tiny circle on the edge of the workboard. We will see how this solution holds as the project develops. We also had a meeting with arts about the project and the plans going forward. Friday 22/09.23 Scrum with whole lab Reached the conclusion that we need to measure how much force is needed to hold down the slices. We have decided to test out a vacuum method because we find it the most flexible solution. It will not make drilling the sides of the slice a cross-contamination hazard, as many of the other solutions do. We will use Monday to prototype and test this idea. Monday 11/09.2023 After many weeks we have finally gotten the basics up and running.
Our next step will be including the lowering and raising of the z-axis in the run-cycles. Friday 15/09.2023 This week we had the TrollLABS Pecha Kucha along with pizza. Before that we cleaned and fixed stuff in TrollLABS that needed cleaning and fixing. This week all members of TrollLABS met and got aquainted. Contact information was shared. |
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