This paper addresses the problem of formation control with collision avoidance, in scenarios comprising robots of heterogeneous shapes and with double integrator dynamics, moving on a plane. The exact shapes of the robots are taken into account in developing two cooperative collision avoidance strategies, and these are based on the collision cone approach. The two collision avoidance strategies treat the acceleration magnitude and direction, respectively, as inputs to facilitate cooperative collision avoidance. Analytical expressions for these cooperative collision avoidance laws are presented. These are then integrated with formation control laws, and simulations demonstrate the satisfactory performance of the overall system.