The PHANTOM haptic interface is a device that measures a user's fingertip position and applies a precisely controlled force vector to it, enabling interaction with virtual objects and remote manipulation. Developed at MIT's Artificial Intelligence Laboratory, the PHANTOM is a desktop device that provides a force-reflecting interface between a human user and a computer. Users insert their index finger into a thimble to interact with the device, which tracks fingertip motion and can exert external forces, creating the illusion of interaction with solid objects. The device is designed with low mass, low friction, low backlash, high stiffness, and good backdrivability to provide realistic tactile sensations. Three key observations influenced the design of the PHANTOM: force and motion are the most important haptic cues, many interactions involve little or no torque, and a small wrist-centered workspace is sufficient. The PHANTOM uses a three-degree-of-freedom thimble-gimbal to simplify programming and mechanism design. The device balances three necessary criteria for an effective haptic interface: free space must feel free, virtual objects must feel stiff, and virtual constraints must not be easily saturated. The PHANTOM's mechanics involve three DC motors with encoders, which track fingertip coordinates and control forces exerted on the user. The device is statically balanced, minimizing the need for active balancing. The PHANTOM's workspace is aligned with the user's wrist, allowing for intuitive interaction. Virtual objects are created using haptic cues, including walls, surfaces, and textures, with the ability to simulate body properties like mass and stiffness. Users of the PHANTOM have reported strong perceptual reactions, including the "phantom" effect when feeling virtual spheres. The device has been used in various labs for research and development, with future work focusing on multi-finger and multi-user interactions. The PHANTOM demonstrates the feasibility of a low-cost system for virtual object interaction, with ongoing research into its performance at different scales.The PHANTOM haptic interface is a device that measures a user's fingertip position and applies a precisely controlled force vector to it, enabling interaction with virtual objects and remote manipulation. Developed at MIT's Artificial Intelligence Laboratory, the PHANTOM is a desktop device that provides a force-reflecting interface between a human user and a computer. Users insert their index finger into a thimble to interact with the device, which tracks fingertip motion and can exert external forces, creating the illusion of interaction with solid objects. The device is designed with low mass, low friction, low backlash, high stiffness, and good backdrivability to provide realistic tactile sensations. Three key observations influenced the design of the PHANTOM: force and motion are the most important haptic cues, many interactions involve little or no torque, and a small wrist-centered workspace is sufficient. The PHANTOM uses a three-degree-of-freedom thimble-gimbal to simplify programming and mechanism design. The device balances three necessary criteria for an effective haptic interface: free space must feel free, virtual objects must feel stiff, and virtual constraints must not be easily saturated. The PHANTOM's mechanics involve three DC motors with encoders, which track fingertip coordinates and control forces exerted on the user. The device is statically balanced, minimizing the need for active balancing. The PHANTOM's workspace is aligned with the user's wrist, allowing for intuitive interaction. Virtual objects are created using haptic cues, including walls, surfaces, and textures, with the ability to simulate body properties like mass and stiffness. Users of the PHANTOM have reported strong perceptual reactions, including the "phantom" effect when feeling virtual spheres. The device has been used in various labs for research and development, with future work focusing on multi-finger and multi-user interactions. The PHANTOM demonstrates the feasibility of a low-cost system for virtual object interaction, with ongoing research into its performance at different scales.