RC Car Project Update



It’s been a long time since anyone has worked on the RC Car project here in the Workshop and since I’m new to this project I figured now is a great time to begin simplifying and streamlining the wiring. The way everything was wired previously was great for prototyping but it left something to be desired for a more polished product. A lot of the wiring had gotten messed up from moving the bikes and just leaving the project unused for so long, so I grabbed a multimeter and began the work by checking all the connections. Previously a breadboard was used to send power to the bikes and also serve as a hub point to read the data from. This created a mess of wires that made it difficult to see how things connect and so I soldered up all the power lines and ground lines and added on a male pin. Now they can be directly connected to the 5v and GND pins on the Arduino itself. I then added male pins to each of the three signal wires so that they too could be plugged directly into the Arduino. With this new setup, I could eliminate the breadboard which cleaned up things nicely. Now that the connections were simplified I verified that everything was working and turned my attention to the RC car itself. When I began working on the car nothing seemed to be responsive. So, I decided to dissemble the system and redo it, following the same guidelines used previously, which fixed the issues. Now both Arduinos are communicating correctly and everything seems to be working except for the throttle which is glitchy at best. Once the receiver side is fully functional I’ll streamline the wiring and clean it up. Things on the to-do list for this project now are:


- Fix Throttle response

- Clean wiring on receiver side

- Add buttons to enable reverse mode

- Reimplement the FPV system

Once all these are done I’ll be designing a PCB that will condense everything and make the project more professional. Below you’ll find the current versions of the code being used on the project.

-Andrew

3D Printed Robotic Hand Project Revisision

After repairing the robotic hand project, the most noticeable flaw was the nest of wires on the receiver. Every servo motor has three wires, with five fingers that means there are fifteen leads going into the breadboard. From there five additional wires need to run to the Arduino for signal control. This leaves this sort of mess:


To solve this mess, I jumped into Circuit Maker, a free PCB design tool from Altium. After selecting my parts I designed this very simple schematic:


With the schematic drawn up I created a PCB file and placed all the components. Normally, routing should be done by hand, but in a circuit as simple as this it really saves a good chunk of time. After running the auto routing I had this:



Each finger will have a 3-pin header, similar to the Power header, and all the signal wires will go from the 5-pin header at the top (labeled OUTPUT). Since all the servo headers will plug directly into the board most of the excess wires will be eliminated.

-Andrew

Electric Skateboard Project Introduction


Electric skateboards are exploding in popularity right now, however, for most people the cost of a good board is too great and the inexpensive options lack in features and range. As a result, a healthy and growing community has formed around DIY Electric Skateboards, where the goal is to create boards that are tailored to the needs of the builder at a fraction of the cost of a good commercial product. For this project, the goal is to create a DIY board that functions at least as well as the most popular electric skateboard, the Boosted Board, for around half of the cost at $700. Some of the features the board will have include: regenerative braking, cruise control, and a reverse mode (flip which side of the board is the ‘front’).

Wiring diagram for power.


The board will be controlled using a Wii Nunchuck controller as well as various electronics for the propulsion system.

The build list is as follows:

Motor 6355 190KV
Mechanical Kit
VESC Open Source ESC
Battery
Controller
Deck
Battery Connectors Set XT60
Battery Connectors Set XT90S
10 AWG Wire
Parrallel Battery Charging Board


-Andrew

Sketch Bot Project Update 1

So, it has been awhile since my last update on the Sketch bot project but this week I was finally able to finish up a wiring diagram and start testing servos with the Arduino unit. I also need to finish redesigning the servo base as well. When I have a finished product I will give more details on that as well. I completed a wiring diagram of how the three servos will be wired to the arduino/breadboard. I was able to do this easily by using the fritzing program.




I also decided on a specific servo motor that I would like to use which you can find via the link below. In the meantime, I decided to test out my wiring diagram to check that everything is copasetic. So, I took advantage of the other servo motors that we had at the shop to test out the Arduino UNO unit as well as a standard servo Arduino code that came with the Arduino program. The good news is that my wiring diagram turns to work out perfectly, but I was not able to test it efficiently with the code I have since I have only one working servo motor at the time.

I am currently waiting for the servo motors to come in so I can properly test the circuit that I made. By the end of next week, I’m looking forward to finishing the base, wiring the servos and testing them, and maybe start to 3d print the bases and arms.

Servo motors

-Kurtis

X-Carve Vacuum Attachment

Having a CNC Router is awesome. Having to constantly clean up shavings is not. To more cleanly operate the X-Carve we decided to go ahead and print a dust shoe to attach a vacuum to. This would allow us to suck up all the shavings and dust as the machine operates and keep the work space cleaner. Searching online we found a design that could be easily printed and attached to the spindle. However, once we printed it we had concerns that the shape of this part would interfere with clamps and thus reduce the overall cutting area we had access to. Considering this, we decided to design our own system for sucking up the mess.

  

Our first attempt had the hose running through two circular brackets, however, once placed on the X-Carve we realized that there would still be clearance issues. After mocking up several ideas, we realized that the original mount could be easily zip tied to and the hose would be no longer interfering with the cut space. We decided to carve out a phone holder to test out the new system. After cutting the holder out we found that there wasn’t enough directionality in the hose, so directly underneath it would be clear but everywhere else would still get covered in dust. To solve this issue we will be designing a nozzle to fit to the tube that will get the suction force closer to the spindle, hopefully solving our issues.

  

-Andrew

Sketch Bot Project Introduction






I am in the very beginning stages of design so there are still a lot of things that can change. I started with the initial physical design of the Bot. So, pieces such as the base, linkages, and the motor extensions are being drafted in Solidworks. After much thought the base of the Sketch Bot is going to be redesigned for more support and stability. The linkages of the Sketch Bot will uphold the original design that we have. It is imperative that the linkages of the Bot are a light-weight design. This helps with the mechanical stress that the motor would have to endure. The theory is that the less mechanical stress the servos must endure, the more accurate the drawing or picture will be.


Project Summary


The Sketch Bot would be able to draw any image that would be uploaded to Microsoft Paint. The Bot would be controlled via arduino, and the arduino would be coded with an algorithm that would be able to read the paint file of the user’s choice. All of the physical components of the Bot would be made out of PLA plastic that would be made by a 3D printer. Arduino programming and Matlab would be used to construct the code for the algorithm to be uploaded to the arduino unit. A long term goal for the Sketch Bot would be able to draw any image on different surfaces.


Project Outline


1. Drawing and Design

2. Wiring and Electronics

3. 3D Print Assembly

4. Create Moving Model

4. MATLAB Code and Arduino

5. Perform Final Tests


Project Materials


Breadboard
Arduino Uno
Servos (3)
Bearings
MATLAB Code Transfer Tool (Arduino)


Project References


Operating Voltage: 4.8- 6.0VDC
Operating Speed: 0.20sec/60degree (4.8V), 0.16sec/60degree (6.0V)
Stall Torque: 5.3kg*cm (4.8V), 7kg*cm (6.0V)
Temperature Range: -20°C ~60°C
Dead Band Width: 4ms
Servo Deluxe HD Ball Bearing Servo Motor

-Kurtis



Up-Cycled Weather Vane: Final Thoughts

Build was successful in that it rotates smoothly in the x and y and is visually playful. I like how the bicycle parts look covered in vinyl. The "flower" stem and  face came out as envisioned
rolling resistance was adequately low but could be lowered further. I think I want to build some wheel having investigated this topic as part of the project and as a commuter cyclist who always wants to go faster.

video

I need to rethink blades to better capture wind. The vinyl on spokes approach is better than the saran wrap I tried but hardly a resounding success. Comments bellow on other approaches would be appreciated. Current improvement that occurs to me is tacking  pre cut blades sheet metal to the spokes.

The weld fit up /tacking was challenging. If I were to repeat might jig. Might notch where I cut off fork tine to improve fit.

Finish of vinyl was good but could have been perhaps better. I had never applied vinyl before and getting it to stick to curved/uneven surfaces was very challenging. I didn’t mind that there was some cracking/bubble lines but probably not the cleanest aesthetic. Might sandblast and powder coat next time to create a more even finish.

Overall was fun and interesting getting used parts and turning into a budding piece of sculpture for a new sculpture artist. Hope you enjoyed!

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