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03.29.17 Independent Study, Journal 9
03.29.17 Wednesday, Catch Up Time
I didn’t work on Independent study. I had to get caught up for my Thursday History and Theory class.
03.30.17 Thursday, Library and Wheels
I mostly worked in the library. I did attempt to put wheels on the robot but it did not work.
03.31.15 Meeting with Gene at 2:00 in Electronics Lab
Gene was a bit late and eating a sandwich so we did not really get started until 2:25. That did not leave a lot of time. He had me go over my design. I already E-mailed him a description of my design rationale but I guess it was not sufficient. He thinks I should trim down the weight and simplify but I am not really sure what his rationale is. I know it would improve battery life, but that really isn’t my primary consideration. I wish he had explained better. I also wish I had been able to ask more articulate questions, I was very very tired. I didn’t even realize it until he left and I felt myself about to cry. That is an uncharacteristic response and indicative of exhaustion. I was having a very hard time formulating questions. I felt like I was doing something wrong and needed to defend myself. My brain was too foggy to parse it all out. Gene was also obviously very tired. He had bags under very red eyes. I am guessing he is over-extended. To be honest, I’d be fine if we didn’t meet at all. I have questions, but if he does not have time to answer them then I will just keep looking until I figure it out. That said, I also do not want to be accused of not doing enough work. If I am not assisted, I may do things in inefficient ways. I am ok with that as long as everyone else is.
Gene also seemed aggravated that I did not follow our original plan. I did notify him about the changes and why. I tried to explain that I just don’t have easy access to a lab full of parts and tools. I can’t just throw things together and test them. There is always some screw or nut or wire that I don’t have and can’t substitute. That’s why I designed this the way I did. It is not as if I have been twiddling my thumbs. I have practices as much as I cab. I read and read and test on breadboards and study everything I can. This is as much as I can do.
I don’t really want to cut my design down. If anything, I want to make it bigger so it has a more solid physicality to it, but I did not get a chance to explain that. If there is a reason that is a bad idea, I’d like to know. I am not trying to be defiant. I just want to understand.
Gene also explained the wiring diagram, but he got a bit short with me when I tried to get him to pause so I could ask a question when I wasn’t following. I ended up not quite understanding what he was saying, but I tried to commit it to memory for later. I think it worked. I think I have mostly figured it out. I e-mailed him a new diagram.
Gene also said I probably don’t need the 5Volt battery. He said Arduino was fine on 12 volts. I said I was concerned about battery life. He suggested I test the motors by just letting them run. MAN do I feel stupid for not thinking of that!
Gene thinks my motor mount may be unstable. He suggested that I should use two clamps per motor. That was my first thought as well. Now that I have better clamps I will redo the system. All I need to do is redo the attachment plate. It shouldn’t be an issue.
Idea: I should construct some kind of stand to hold motors still when I want to prototype. I did it with clamps before but it was a pain. I could probably attach one of my hose clamps to a stand and that would be more effective.
I stopped at a Thrift store on my way to the meeting. I got one really big Monster Truck car and a bunch of little ones. I also got a few weird miscellaneous electronic toys and a small LCD monitor. When I came home I was tense. Destroying all those cars was AWESOME. It was great fun and I got a bunch of good stuff. I think I can make me a giant robot using the struts and wheels from the big monster truck. I’m so pleased! I’ll need to know a lot more about motor construction to do it, but I am saving those wheels.
Last time I did this I kept it orderly. This time I destroyed my living room with junk.
04.01.17 Email/Power System
I had to clean up from the disaster.
I sent Gene the following E-mail:
I sent the power diagram from my phone. I hate typing on the phone so I am explaining here.
I think I have it right but I wrote two questions on the diagram. I am typing them here since my handwriting is messy,
The idea is:
- Parallel connection so that power supply system is upgradable. I want to be able to use either 1 or 2 batteries depending on what I later find that I need and can charge on only one port.
- Ports and Dupont connectors for easy disconnect reconnect if needed
- Safely switch from charging to power
Question: Is the isolation enough? I understand that it can be bad to charge and power at the same time.
Note: Some sources said important to connect – of Battery A and + of battery B to the charger port because it balances the load and prevents damage to battery but also said it does not matter on low Amps. I wasn’t sure so I did it for safety. (I lost my best source, will find later)
- When “Power All” is on, selectively turn individual components on/off so that I can safely remove parts without having to access the battery or rewire everything.
Question: Do individual on/off switches get a wire in and a wire out on each terminal? Also, does it matter if I end up using the 3 terminal switches with only 2 terminals used? I don’t have any 2 terminal switches.
Motor Power Supply Notes: I do understand that the 2 big motors will draw a lot of power. The big RC car I took apart only had one motor that was similar. That car was 2 feet long by 18 inches high and quite heavy so it seems obvious I can reduce battery use by switching to a one motor system. However, that is something to deal with later. , I don’t have time or to design the mechanics of a one motor system. The modular design should allow me to make those kinds of changes later when I am more comfortable with the design. Right now I care more about being able to work with input/output responses than working out better driving systems. Motor/driver functionality will be enough for that.
P.S. Wheels still are not on. Washer was the wrong size. Need to go find a smaller one.
The saga of the wheels has been ongoing and tedious but now it is fixed. I managed to salvage appropriate wheels from a toy and I got them attached. The motor mount looks terrible. The wheels are not well aligned, but right now I just don’t care. I just want the damn thing to work!
I hooked up a power system. I finally figured out how to make reliable Dupont connections. Sadly, some of the first ones are unreliable and the power system gets buggy. I think I also have problems with the soldering of the wires to the switch. I saw that we have some of the connectors I need at the IMRC. I will take in some plugs and look for them there. I would like to order some but they seem to come in big sets of many gauges of wire and Arduinos mostly just use 22 gauge so I’d only be able to use a few of them.