sk8

robotzone, parent company, winfield, kansas
actobotics, parts brand name
servocity, distributor

skateboard deck

• length: 700mm
• width: 200mm (at widest point)
• height: 110mm (to top of deck, when flat)
• height low edge: 90mm (at maximum tilt, at widest point)
• height high edge: 130mm

weight plate

• id: 25mm (.98in)
• od: 150mm (5.9in)
• weight: 2.5kg

linear actuator (obsolete idea)

• qty: 2 pieces,
• retracted length: 250mm (10 in),
• extended length: 370mm (15 in),
• stroke length: 120mm (5 in),
• speed: 60mm/s (2.5 in/s),
• force: 30 N
• include: 4 mounting brackets, 2 at each end of each piece

springs

• closed ground
• outside diameter 24 mm (.944882 in)
• free length 16 mm (.629921 in)
• wire diameter 1mm (.0393701 in)
• coils 4 total
• product number: century 3663
• supplier: century spring corp, mw industries,

object detection

pad angles

Adjust speed for helm, for deck slant

• Arrows rt left center
• Shift up down, go stop
• Calibrate

Dorm room swarm motion capture https://m.youtube.com/watch?v=0ql20JKrscQ&pp=ygUYRXNwMzIgZHJvbmUgc3dhcm0gdmlzaW9u

Diy drone https://th.aliexpress.com/item/32776829828.html?gatewayAdapt=glo2tha

Pull-up resistor project https://m.youtube.com/shorts/y_QIEyC-uUk

Calculate turning radius and use this to plot destination point to the right or left of the cone

• Max steering angle 27°
• wheelbase WB = 12.5cm
• Turning radius TR = WB/tan(a)
• TR = 125mm / tan(27)
• TR = 125mm / 0.509525449
• TR = 245mm

Make chart of deck angle to rudder angle
Find equation or interpolation
Interpolate table of deck tilt to steering angle then check a deck tilt of half.

• Max deck tilt 18°
• Max steering angle 27°

steering angle = comparison of front and back wheels

• the pair of right wheels and the pair of left wheels will have the same angle
• steering angle = rudder angle = wheel angle

Develop direct ratio for rudder to right wheel throttle.

• Consider turning radius and circumference of each wheel.
• develop ratios for both right and left wheels
• In future, we might use two motors

radius = 245mm circumference = 245 * pi = 769.7

axle width = right wheel TR left wheel circumference

speed differential for each wheel depending on deck tilt

A type of controller.

Develop PID for helm to rudder

Implement IMU on sk8 to get deck roll angle

• Digital motion processor (DMP), included on the mpu 6050.

What is a DMP?

• gyros have Lots of fluctuation
• even when sitting motionless on the floor
• Noise in the data
• Smoothing or Averaging
• Fusion algorithms: of data from multiple sensors: gyroscope and accelerometers

Inertial navigation system

Kalman filter

When stationary, every object is experiencing 1G of downward Force.

make a map of yellow cones, center points

x cover motor with tape

make another photo set

write python code to:

find the wheels, center points
calc the centerpoint and angle of the sk8 (two choices)
weight target, centerpoint
calc the vector of the sk8, ie, change angle to vector (one choice)

convert python code to c++ and install on awacs

implement esp now to send coordinates from awacs to sk8

write code on sk8 to plot course (taken from previously written python program)

write code to

find yellow cones
make a list of coordinates
send changes from awacs to sk8

find earlier python code for plotting course

wheels black 0d0e06, threshhold 5

cones yellow bcb44f b7b159 9b925b

Azimuthal projection with minimum interruption
https://en.m.wikipedia.org/wiki/Interruption_(map_projection)

Arduino IDE settings:

• Board: Arduino Nano ESP32
• Port: ttyACM0

MPU6050

IMU AHRS

Inertial Navigation System

Quiic cable

ESP32-CAM, by Espressif and AI Thinker
Best source of info: https://github.com/espressif/esp32-camera

Arduino IDE settings:

• Board: AI Thinker ESP32-CAM
• Port: ttyUSB0

Isolate minimal code to

1. return Jason from url get
2. set camera settings'
3. return image from camera

Is it possible to edit EXIF header?B

3 lenses: 60, 120, 160 degrees fov wide

photo folders:

• ~/sk8mini/awacs/photos/60/
• ~/sk8mini/awacs/photos/120/
• ~/sk8mini/awacs/photos/160/

webapps/robots/robots/sk8mini/awacs/cam.ino

• empty setup() and loop() methods
• not used

robots/sk8mini/awacs/example/CameraWebServer/CameraWebServer.ino

• modified to connect to wifi as access point
  • connected as station: slow
  • connected as access point: less slow
• implement webserver commands
  • /index.html
  • /capture
  • :81/stream

cam.py

• connect to the wifi
• call the webserver on the awacs
• use the esp32-cam “capture” command
• receive the returned image
• save it to hard disk

two decisions:

• framesize
• lens
  • fov
  • distortion
  • clarity
  • color

original
label: OV2640
fov: 60 degrees
a_ov2640_svga_8.jpg

label: DCX 2640 V2
fov: 120 degrees
long lens
maximum fish-eye type of distortion
filename: d_longlens_svga_8.jpg

label: DCX 2640 V2
fov: 160 degrees
filename: b_dcxv2_svga_8.jpg

label: DC 2640 V3 R
fov: 160 degrees
filename: c_dcv3r_svga_8.jpg