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Tony's Intertwingled Memex • Reference Manual

Lidar Safety Envelopes (Robotics & Computer Science)

Formulas & Definitions

In autonomous vehicle design, a lidar sensor scans the surroundings by emitting light pulses across a specific field of view. The domain of the range-finding function is restricted by the sensor's physical limits: the horizontal scanning angle θ\thetaθ is restricted to [−π3,π3]\left[-\frac{\pi}{3}, \frac{\pi}{3}\right][−3π​,3π​] radians, and the radial distance ddd is restricted to [0.1,150][0.1, 150][0.1,150] meters.

To determine how the vehicle should respond to obstacles, software engineers program a piecewise control function A(d)A(d)A(d) to evaluate safety zones:

A(d)={Full Emergency Braking:0.1≤d<3Proportional Deceleration:3≤d<15Maintain Cruise Speed:15≤d≤150A(d) = \begin{cases} \text{Full Emergency Braking} & : 0.1 \le d < 3 \\ \text{Proportional Deceleration} & : 3 \le d < 15 \\ \text{Maintain Cruise Speed} & : 15 \le d \le 150 \end{cases}A(d)=⎩⎨⎧​Full Emergency BrakingProportional DecelerationMaintain Cruise Speed​:0.1≤d<3:3≤d<15:15≤d≤150​

Determine the vehicle's response and safety state if an obstacle is detected at a distance of:

  1. d=2 metersd = 2\text{ meters}d=2 meters
  2. d=10 metersd = 10\text{ meters}d=10 meters
  3. d=80 metersd = 80\text{ meters}d=80 meters