Recent content by TaurusI76

  1. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    I have a follow up question to the above formulas: The formula does not work if both accelerations ##a_x## and ##a_1## are 0 (Scenario: car 1 is already at its max speed, and so is car 2. But due to a higher max speed car 2 will eventually catch up and will have to slow down). In this case...
  2. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    So, just to complete this: I've got ##g+h(t_1+t_2)+\frac{1}{2}it_1^2+\frac{1}{2}jt_2^2-a_1t_1t_2 = 0## where ##e=\frac{a_2-a_x}{a_x-a_1}## ##f=\frac{v_y-v_x}{a_x-a_1}## ##g=p_x-p_y-d## ##h=v_x-v_y## ##i=a_x-a_1## ##j=a_x-a_2## Given that ##t_1=e*t_2+f## by substituting this in the top...
  3. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    OK, so I've got ##t_1=et_2+f## and ##e=\frac{a_2-a_x}{a_x-a_1}## and ##f=\frac{v_y-v_x}{a_x-a_1}## Then, I've got ##P_x = P_y + d## which means that ##p_x + v_x (t_1+t_2) + \frac{1}{2} a_x (t_1+t_2)^2 = p_y + v_y (t_1+t_2) + \frac{1}{2} a_1 t_1^2 + a_1 t_1 t_2 + \frac{1}{2} a_2 t_2^2 + d## and...
  4. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    How did you get to that? What are e and f made up of? When I solve for ##t_1## I end up with ##t_1## = (-##a_x## ##t_2## + ##a_2## ##t_2## - ##v_x## + ##v_y##) / (##a_x## - ##a_1##)
  5. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    That gives me one hell of a long formula! Is that supposed to be that long? (Because the equation for ##t_c## = (...) already is a long equation that I have to substitute in a number of places) Also, I struggle to find a quadratic formula in the form of ax2 + bx + c = 0. ##t_d## is all over the...
  6. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    @mfb: you are right, the accelerations are known. And BTW, I think my initial question was a bit unclear. I should have asked not only if there is a solution, but what that solution is (because that's what was unclear to me as well). But the max speed is ok, that's a variable I already have in...
  7. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    How does tc fit into the final speed of car 2 function? I think that's the only part I don't get about your procedure. I got: vf = v21 + a21 * ta + a22 * td ... so what do I do with tc here?
  8. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    Yes, I eventually want to cover that with different driver profiles (the whole thing will be used in a video game). But since the accelerations are always defined (default would be equal acceleration and deceleration, 'eco-friendly' driver would be determined by how big the deceleration from...
  9. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    Thanks Andrew for clearing that up. I was suspecting that I had too little known values to solve it. However, in the simulation that I use this, I define the acceleration and deceleration rates. The cars have a max acceleration and deceleration and they use 'default' acceleration/deceleration...
  10. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    I still don't get how I can get rid of some of the unknowns. I updated the graph a little (for my better understanding) What I managed to caluclate so far is the time/distance where the green line crosses the red line. But that is not of a lot of use to me, because the deceleration would...
  11. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    I'm not sure if I can follow your line of thought. What would t1 and t2 stand for then? I suppose t1 is the time that car 2 accelerates and t2 the time it decelerates - correct? So what equations would I use to calculate them? If I use the same formula base as above (v * t + 0.5 * a * t2), how...
  12. TaurusI76

    When should an accelerating car start braking to match another car's speed?

    Homework Statement I have the following situation: car 1 is distance di ahead of car 2. Car 1 has either a constant speed v1 or accelerates with a1 (I eventually want to cover both cases). Car 2 accelerates faster than car 1. Car 2 is eventually going to catch up with car 1. I want to calculate...
  13. TaurusI76

    Struggling with Calculus in Game Development - Seeking Advice!

    I'm a software engineer/game developer and I'm currently developing a game that requires me to do some calculations that are based on physics. I guess I was ok at maths/physics up to the 'precalculus' level, but started to struggle at the calculus level. That's why I need some help on some...