Certain aspects relate to systems and techniques for detection of undesirable forces on one or more surgical robotic arms. In one aspect, there is provided a system including a robotic arm, including: two linkages, a joint, a torque sensor, and an instrument device manipulator (IDM). The system may further include a processor configured to measure a first torque value at the joint based on an output of the torque sensor and determine a second torque value at the joint based on a position of the robotic arm. The second torque value may be indicative of a gravitational component of the torque between the two linkages. The processor may be further configured to determine a force at the IDM based a difference between the first and second torque values and determine whether the robotic arm has collided with an object or misaligned based on the force at the IDM.