Winter Wonderland - Days 5 and 6/10! (#hardware-party)
I passed out before I could write an update yesterday, so this'll contain my progress for both today and yesterday 😅
Using bullet points because they seemed to work well for my last update:
• Printed motor slider block
• Proceeded to break motor slider block when I rode my bike without metal plates clamping the plastic :|
• Soldered banana plugs to ESC motor output
• Soldered hall effect sensor to long wire and crimped end to plug into ESC connector
• Added y-joint to power throttle and crimped throttle sense cable for ESC as well
• Assemble motor and speed controller to bike (use broken slider block because break is along layer lines and those will be clamped by aluminum plates)
• Cable management for wires on bike
• Hot glue hall effect brake setup to handles (only temporarily)
• Testing :)
CAD for reference
Winter Wonderland - Day 4/10! (#hardware-party)
I'm super tired today, so I'm going to keep this update short with bullet points:
• Got motor mounting plate made on router!
• Received last connector I needed to hookup battery to speed controller
• Soldered different connector types to wire
• Made first basic configuration for speed controller (completely untested)
• 3D print motor mount slider block
• 3D print pulley
• Assemble all major components to bike
• Wire everything (a lot of things!)
• Cable management
• Test the esc configuration
I thought of another addition to the project as well. It would be nice to have a small bike computer with gps and a high contrast e-ink style display. This is definitely not going to be possible in these 10 days, but it's another thing to do after the base bike is done!
As always, here's the CAD for reference, and I'm open to suggestions!
(The pictures will be better tomorrow I promise)
Winter Wonderland - Day 3/10! (#hardware-party)
I wasn't able to get my partial depth cut motor plate made today, so I put my attention towards some newly received hall effect sensors! Unlike the last pack I mistakenly ordered, these are ratiometric. This means that their output voltage is proportional to the strength of the magnetic field present (the ones I brought previously only functioned as magnetic switches).
This proportionality is important because these sensors will sense how much I pull the brake lever in order to vary the strength of regen braking. Having varying voltage also means that I'm going to have to tune the speed controller with minimum and maximum voltages output by the sensor.
Testing time! I only slightly burned myself by shorting the sensor, but the sensor was fine. After that slight mishap, I hooked it up to the oscilloscope and grabbed a neodymium magnet I plan to use on the bike. With that specific magnet, I tested the detection range of the sensor and from that determined where the magnet should be mounted for the greatest (while still detectable) range of brake handle motion.
I plan to use good old hot glue to mount the hall effect sensor and magnet to the bike, but if it ends up too janky, I'll design a 3D printed solution.
Aside from machining the motor mounting plate, I also need to 3D print my large pulley. Once that's done, I can get to assembling V1 onto the bike!
CAD for reference
Winter Wonderland - Back Again for Day 2/10! (#hardware-party)
Today has been a pretty busy day for me, so I didn't get quite as much done as I wanted to. Nevertheless, progress has been made and you're here to see it.
First things first, I went through three different motor mount bracket revisions trying to get the angles just right (a tilted motor would lead to belt wear nightmares down the road).
After getting the motor mount sides printed, I decided to knock out a couple easy tasks, so I mounted the battery to the bike, which was easy to do with the water bottle holes already found standard on the bike frame. I also printed the mount for the speed controller (out of PETG for heat resistance) and gave it a test fit on the bike. While the part looks super pretty and clamped on to the frame well, it didn't have the friction to resist my pushing it down the tube. To solve this problem, I'm thinking of lining the inside of the clamp with electrical tape for its thin but rubbery surface.
One more super exciting thing - I got some of my aluminum plates machined at robotics! All I need now is the motor mount plate, which is a little bit more complex with its partial depth cut wings.
Just like the last post, feel free to message me with any questions or input!
CAD for reference
Winter Wonderland Day 1/10 (#hardware-party)
The day has come - I finally started working on my eBike project! (definitely didn’t start the cad early 🙈 )
After putting some “finishing” touches on the cad, I 3D printed a side of my motor mount bracket to make sure I got my angles right…
Low and behold I had to make adjustments so now v2 is on its way 😂 .
While those parts were printing, I got to thinking about what communication scheme I’m going to use for control: Currently leaning towards using built in ADC for throttle and a raspi pico interpreted signal from a Hall effect sensor for brakes.
Feel free to message me if you have any questions or some input!