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Introduction

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• Parameters

  • v: (float) final velocity of the car to accelerate to, (m/s)

  • vwind: (float) velocity of the wind relative to the car, (m/s)

  • v_old: (float) initial velocity of the car, (m/s)

  • theta: (float) angle that must be climbed (radians) personally don’t understand why “climb” matters and not just angle of elevation

  • timestep: (float) Time between measurements, (s)

    • usually calculated dist / ((v + old_v)/2), dist being the distance between two points in elevation profile, e_profile.

• Returns

  • Fmotor: (float) Force of motors required to accelerate to a certain velocity in a certain time (N)

• Note

  • If v or v_old greater than maximum speed or less than minimum speed, it is caught in the function and whatever is out of bounds is set to maximum speed or minimum speed

  • Ffric, Fdrag , Fg , Fa, and ultimately Fmotor to be all calculated inside the function, using parameters and constants

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We are doing (velocity) - (force) + (impulse) to get final velocity. What are we doing here?? We propose that we use distance to calculate the maximum velocity.

The energy_used() function

• Parameters

  • v_profile: (float list) A list of the same length as the e_profile with each element representing the average velocity (m/s) required for the car to move at each section on the e_profile

  • e_profile: (2D float list)

    • Each row represents a section of a course

    • column 0: the pitch/slope/steepness of the section (rad)

    • column 1: the length/distance of the section (m)

  • distance: (float) distance of each section (m/s)

    • we never use this in the function, as we have length of each sections already stored in e_profile. Useless parameter?

• Returns

  • energy: (float) Total energy used if the entire v_profile was to be followed (J)

    • Calculated by summing force_req() * e_profile[point][1] (length of section at index point) for each point/section in v_profile and e_profile.

• Note

  • If v or v_old greater than maximum speed or less than minimum speed, it is caught in the function and whatever is out of bounds is set to maximum speed or minimum speed.

  • Error if the length of v_profile and e_profile do not match

  • In the objective function (shown below) that we are trying to minimize, it basically returns the value of energy_used()function. Thus in Optimizer we are trying to minimize the return value of energy_used()

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