Envision a poster featuring the retro-futuristic robot extending its hand for a handshake, inviting the audience to interact. The image type is a digital illustration with a mix of retro and futuristic elements. The artistic style is friendly and approachable, with a focus on bold lines and vibrant colors. The medium is digital software with a focus on neon lighting and retro-style textures. The camera settings are aperture f/2.2, shutter speed 1/100s, and a 35mm lens. The lighting setup is a mix of warm, golden light and cool, futuristic glow. The background is a bright, gradient blue, with subtle texture resembling retro-futuristic concept art. The focus points are the robot's hand and the inviting expression. Apply a Vignette effect to enhance the sense of approachability and friendliness.