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This study investigates a novel phenomenon of lift generation around a sphere by pneumatically manipulating its surface topology with an asymmetric roughness distribution. A comprehensive series of systematic experiments were conducted for Reynolds numbers ($Re = U_{\infty} d/\nu$, where $U_{\infty}$ is the fluid velocity, $d$ is the sphere diameter, and $\nu$ is the fluid kinematic viscosity) ranging from $6\times10^4$ to $1.3\times10^5$, and dimple depth ratios ($k/d$, where $k$ is the dimple depth) from $0$ to $1\times10^{-2}$ using a smart morphable sphere with one smooth and one dimpled side. The findings show that an asymmetrically rough sphere can generate lift forces up to 80\% of the drag, comparable to those produced by the Magnus Effect. The dimple depth ratio affects both the $Re$ at which lift generation begins and the maximum lift coefficient ($C_L$) achievable. The optimal $k/d$ for maximum lift varies with $Re$: deeper dimples are needed at low $Re$, while shallower dimples are more effective at high $Re$. For a fixed $Re$, increasing $k/d$ monotonically increases lift until a critical $k/d$ is reached, beyond which lift decreases. Particle Image Velocimetry (PIV) revealed that dimples delay flow separation on the rough side while the smooth side remains unchanged, resulting in asymmetric boundary layer separation, leading to wake deflection and lift generation. Beyond the critical $k/d$, the flow separation location moved upstream, increasing the size of the rear wake, reducing wake deflection, and thus decreasing lift. Overall, this study establishes the foundation for wake control over bluff bodies and paves the way for real-time manoeuvring applications.

Dimples on a sphere's surface can lead to significant drag reduction. However, the optimal dimple depth to minimize the drag varies with the Reynolds number ($Re$). In this study, a smart surface-morphing technique is devised that can adjust dimple depth based on the flow conditions to minimize drag across a wide range of $Re$ values. By depressurizing the core of a rigid skeleton enclosed with a thin latex membrane, the dimple depth can be precisely controlled in response to flow velocity changes. A comprehensive series of systematic experiments are performed for Reynolds number range of $6\times10^4 \leq Re \leq 1.3\times10^5$, and dimple depth ratios of $0 \leq k/d \leq 2\times10^{-2}$ using the morphable sphere. It is observed that the dimple depth ratio $k/d$ significantly affects both the onset of the drag crisis and the minimum achievable drag. As $k/d$ increases, the critical Reynolds number for the drag crisis decreases. However, the minimum achievable drag coefficient decreases as $k/d$ increases. By carefully adjusting the $k/d$ to $Re$ using the morphable approach, our experiments show that $C_D$ reductions up to 50 % can be achieved when compared to a smooth counterpart for all the $Re$ considered. For a constant $Re$, drag reduces as $k/d$ increases. However, there is a critical threshold beyond which drag amplification starts to occur. Particle image velocimetry (PIV) reveals a delay in flow separation on the sphere's surface with increasing $k/d$, causing the separation angle to shift downstream. However, when $k/d$ exceeds the critical threshold, flow separation moves upstream, causing an increase in drag. By using the experimental data, a control model is also developed relating optimum $k/d$ with $Re$ to minimize drag. This model also serves as the basis for adaptive drag control of the sphere for a wide range of Reynolds number.