In the video https://youtu.be/BaeoT4V_PN4 the Mindstorms 51515 snake is programmed in Python. There is a video on how to program the snake with Word Blocks (Scratch programming language) https://youtu.be/qKI21klIH5U which also adds remote control, but the motion loop is not super-tight.
To get the tightest possible movement one need to program it in Python, in this case we have to give up the remote control so the snake will just move forward but will do so in greater style! There is also the potential to utilize the distance sensor to make a wall-avoiding snake for those who want to take it a step further. Programming in Python requires quite a few lines of code to be written. Luckily Anton from Antons Mindstorms Hacks (https://antonsmindstorms.com/) has provided a library that makes all the heavy lifting and allows for very easy animation of the robots.
- Read the article at https://antonsmindstorms.com/2021/02/20/keyframe-motor-animation-with-python-for-mindstorms-and-spike-robots/ and also take the time to check out the Youtube video where he demonstrates how to animate his Tars model.
- Create a new Python project in the Mindstorms App and then copy and past the entire biolerplate code from here: https://github.com/antonvh/mp-robot-tools/blob/master/mechanism.py
Next step is to modify the "boilerplate control loop" that is found at the very bottom of your Python project. Change it into this:
### Boilerplate control loop here
from mindstorms import DistanceSensor
# Initialize the Distance Sensor.
distance = DistanceSensor('B')
distance.light_up_all()
j1 = hub.port.A.motor
j2 = hub.port.C.motor
j3 = hub.port.F.motor
j4 = hub.port.D.motor
a = 50 # Amplitude
p = 1200 # period
o=36 # offset
# Phase displaced sine_wave functions for each motor
j1_func = sine_wave(amplitude = 20, period=p)
j2_func = sine_wave(amplitude = a, period=p, offset = o)
j3_func = sine_wave(amplitude = a, period=p, offset = 180+2*o)
j4_func = sine_wave(amplitude = a, period=p, offset = 180+3*o)
motors = [j1, j2, j3, j4]
motor_functions = [j1_func, j2_func, j3_func, j4_func]
my_mechanism = Mechanism(motors, motor_functions)
my_mechanism.shortest_path_reset()
timer= AMHTimer()
while timer.time < 30000:
my_mechanism.update_motor_pwms(timer.time)
utime.sleep_ms(10)
my_mechanism.stop()
raise SystemExitDownload the program to a program slot of your choosing and start it