58 | | The Social Forces approach is based on the idea that pedestrian movement is results from forces exerted on the pedestrian by its surroundings and goals. These forces can be either '''repulsive''' or '''attractive'''. Repulsive forces are associated with obstacles such as buildings, trees or other pedestrians. The current goal of each pedestrian exerts an attractive force on it. |
| 58 | The Social Forces approach is based on the idea that pedestrian movement is results from forces exerted on the pedestrian by its surroundings and goals. These forces can be either '''repulsive''' or '''attractive'''. Repulsive forces are associated with obstacles such as buildings, trees or other pedestrians. The current goal of each pedestrian exerts an attractive force on it. The resulting force on a **pedestrian α** is the sum of all attractive and repulsive forces, |
| 59 | {{{ |
| 60 | #!Latex |
| 61 | \begin{equation*} |
| 62 | \vec{F_{\alpha}} = \sum_i{\vec{F_i}}. |
| 63 | \end{equation*} |
| 64 | }}} |
| 65 | The forces considered here are repulsion by obstacles and other pedestrians as well as the acceleration term driving the pedestrian toward its target. \\\\ |
| 66 | The repulsion by an '''obstacle //B//''' is defined as |
| 67 | {{{ |
| 68 | #!Latex |
| 69 | \begin{equation*} |
| 70 | \vec{F}_{\alpha B} = - \nabla_{\vec{r}_{\alpha B}} U(|\vec{r}_{\alpha B}|), |
| 71 | \end{equation*} |
| 72 | }}} |
| 73 | with the repulsive potential |
| 74 | {{{ |
| 75 | #!Latex |
| 76 | \begin{equation*} |
| 77 | U = (|\vec{r}_{\alpha B}|) = U_0 \cdot e^{-|\vec{r}_{\alpha B}|/R_{B}}. |
| 78 | \end{equation*} |
| 79 | }}} |
| 80 | In the MAS, //U_0// is [wiki:/doc/app/agtpar#repuls_wall repuls_wall] and //R_B// is [wiki:/doc/app/agtpar#sigma_rep_wall sigma_rep_wall].\\\\ |
| 81 | The repulsion by another **pedestrian //β//** is defined as |
| 82 | {{{ |
| 83 | #!Latex |
| 84 | \begin{equation*} |
| 85 | \vec{F}_{\alpha \beta} = - \nabla_{\vec{r}_{\alpha \beta}} V(|\vec{r}_{\alpha \beta}|), |
| 86 | \end{equation*} |
| 87 | }}} |
| 88 | with the repulsive potential |
| 89 | {{{ |
| 90 | #!Latex |
| 91 | \begin{equation*} |
| 92 | V = (|\vec{r}_{\alpha \beta}|) = V_0 \cdot e^{-|\vec{r}_{\alpha \beta}|/R_{\beta}}. |
| 93 | \end{equation*} |
| 94 | }}} |
| 95 | In the MAS, //U_0// is [wiki:/doc/app/agtpar#repuls_wall repuls_wall] and //R// is [wiki:/doc/app/agtpar#sigma_rep_wall sigma_rep_wall].\\ |
| 96 | |
| 97 | |