Haptic Input Research Articles

Local field potential sharp waves with diversified impact on cortical neuronal encoding of haptic input

Cortical sensory processing is greatly impacted by internally generated activity. But controlling for that activity is difficult since the thalamocortical network is a high-dimensional system with rapid state changes. Therefore, to unwind the cortical computational architecture there is a need for physiological ‘landmarks’ that can be used as frames of reference for computational state. Here we use a waveshape transform method to identify conspicuous local field potential sharp waves (LFP-SPWs) in the somatosensory cortex (S1). LFP-SPW events triggered short-lasting but massive neuronal activation in all recorded neurons with a subset of neurons initiating their activation up to 20 ms before the LFP-SPW onset. In contrast, LFP-SPWs differentially impacted the neuronal spike responses to ensuing tactile inputs, depressing the tactile responses in some neurons and enhancing them in others. When LFP-SPWs coactivated with more distant cortical surface (ECoG)-SPWs, suggesting an involvement of these SPWs in global cortical signaling, the impact of the LFP-SPW on the neuronal tactile response could change substantially, including inverting its impact to the opposite. These cortical SPWs shared many signal fingerprint characteristics as reported for hippocampal SPWs and may be a biomarker for a particular type of state change that is possibly shared byboth hippocampus and neocortex.

Impact Localization for Haptic Input Devices Using Hybrid Laminates with Sensoric Function

The required energy savings can be achieved in all automotive domains through weight savings and the merging of manufacturing processes in production. This fact is taken into account through functional integration in lightweight materials and manufacturing in a process close to large-scale production. In previous work, separate steps of a process chain for manufacturing a center console cover utilizing a sensoric hybrid laminate have been developed and evaluated. This includes the process steps of joining, forming and inline polarization as well as connecting to an embedded system. This work continues the research process by evaluating impact localization methods to use the center console as a haptic input device. For this purpose, different deep learning methods are derived from the state of the art and analyzed for their applicability in two consecutive studies. The results show that MLPs, LSTMs, GRUs and CNNs are suitable to localize impacts on the novel laminate with high localization rates of up to 99%, and thus the usability of the developed laminate as a haptic input device has been proven.

User Study to Validate the Performance of an Offline Robot Programming Method That Enables Robot-Independent Kinesthetic Instruction through the Use of Augmented Reality and Motion Capturing

The paper presents a novel offline programming (OLP) method based on programming by demonstration (PbD), which has been validated through user study. PbD is a programming method that involves physical interaction with robots, and kinesthetic teaching (KT) is a commonly used online programming method in industry. However, online programming methods consume significant robot resources, limiting the speed advantages of PbD and emphasizing the need for an offline approach. The method presented here, based on KT, uses a virtual representation instead of a physical robot, allowing independent programming regardless of the working environment. It employs haptic input devices to teach a simulated robot in augmented reality and uses automatic path planning. A benchmarking test was conducted to standardize equipment, procedures, and evaluation techniques to compare different PbD approaches. The results indicate a 47% decrease in programming time when compared to traditional KT methods in established industrial systems. Although the accuracy is not yet at the level of industrial systems, users have shown rapid improvement, confirming the learnability of the system. User feedback on the perceived workload and the ease of use was positive. In conclusion, this method has potential for industrial use due to its learnability, reduction in robot downtime, and applicability across different robot sizes and types.

Multisensory and biomechanical influences on postural control in children

Children’s ability to maintain balance requires effective integration of multisensory and biomechanical information. The current project examined the interaction between such sensory inputs, manipulating visual input (presence vs. absence), haptic (somatosensory) input (presence vs. absence of contact with a stable or unstable finger support surface), and biomechanical (sensorimotor) input (varying stance widths). Analyses of mean velocity of the center of pressure and the percentage stability gain highlighted the role of varying multisensory inputs in postural control. Developmentally, older children (6–11 years) showed a multisensory integration advantage compared with their younger counterparts (3–5.9 years), with the impact of varying sensory inputs more closely akin to that seen in adults. Subsequent analyses of the impact of anthropometric individual difference parameters (e.g., height, leg length, weight, areas of base of support) revealed a shifting pattern across development. For younger children, these parameters were positively related to postural stability across experimental conditions (i.e., increasing body size was related to increasing postural control). This pattern transitioned for older children, who showed a nonsignificant relation between body size and balance. Interestingly, because adults show a negative relation between anthropometric factors and stability (i.e., increasing body size is related to decreasing postural control), this shift for the older children can be seen as a developmental transition from child-like to adult-like balance control.

Speech-derived haptic stimulation enhances speech recognition in a multi-talker background

Speech understanding, while effortless in quiet conditions, is challenging in noisy environments. Previous studies have revealed that a feasible approach to supplement speech-in-noise (SiN) perception consists in presenting speech-derived signals as haptic input. In the current study, we investigated whether the presentation of a vibrotactile signal derived from the speech temporal envelope can improve SiN intelligibility in a multi-talker background for untrained, normal-hearing listeners. We also determined if vibrotactile sensitivity, evaluated using vibrotactile detection thresholds, modulates the extent of audio-tactile SiN improvement. In practice, we measured participants’ speech recognition in a multi-talker noise without (audio-only) and with (audio-tactile) concurrent vibrotactile stimulation delivered in three schemes: to the left or right palm, or to both. Averaged across the three stimulation delivery schemes, the vibrotactile stimulation led to a significant improvement of 0.41 dB in SiN recognition when compared to the audio-only condition. Notably, there were no significant differences observed between the improvements in these delivery schemes. In addition, audio-tactile SiN benefit was significantly predicted by participants’ vibrotactile threshold levels and unimodal (audio-only) SiN performance. The extent of the improvement afforded by speech-envelope-derived vibrotactile stimulation was in line with previously uncovered vibrotactile enhancements of SiN perception in untrained listeners with no known hearing impairment. Overall, these results highlight the potential of concurrent vibrotactile stimulation to improve SiN recognition, especially in individuals with poor SiN perception abilities, and tentatively more so with increasing tactile sensitivity. Moreover, they lend support to the multimodal accounts of speech perception and research on tactile speech aid devices.

Aging effects of haptic input on postural control under a dual-task paradigm.

Postural control relies on three principal sensory systems: vision, vestibular and proprioceptive; that are affected by aging. When performing a cognitive task concomitantly with a motor task, those sensory impairments lead to even greater deleterious effects on balance. We aimed to study the effects of a sensory aid (a light touch) on a dual task paradigm and sought to understand the different responses on balance due to aging. Fifty healthy and highly physical active women were divided in two groups: young (N=25, 24.2±4.0years) and older adults (N=25, 67.3±4.2years). In a random and balanced order, all participants performed five tasks: Stroop test while seated (Seated); Stroop test while standing quiet (ST); Standing quiet (BL); Standing quiet with a haptic input (LT); and Stroop test with a haptic input while standing quiet (SL). In the Stroop test, older women committed more errors (50 vs 11 errors, p<0.001) and had higher reaction time (1.001±0.191 vs 0.699±0.081s, p<0.001). The haptic input (LT) reduced all body sway parameters, in both groups, regardless the condition. This means that postural control under a dual task paradigm (ST) deleterious effect can be mitigated by a haptic input.

Development and evaluation of a simulator for endoscopic sinus surgery

Endoscopic surgical procedures have been established as gold standard in sinus surgery. Challenges for surgical training have been addressed by the use of virtual reality (VR) simulators. To date, a number of simulators have been developed. However, previous studies regarding their training effects investigated only medically pretrained subjects or the time course of training outcomes has not been reported. A computer tomography (CT) dataset was segmented manually. A three-dimensional polygonal surface model was generated and textured using original photographic material. Interaction with the virtual environment was performed using a haptic input device. For the investigation of training outcomes with the simulator, the parameters duration and the number of errors were recorded. Ten subjects completed a training consisting of five runs on ten consecutive days. Within the whole exercise period, four subjects reduced the duration of intervention by more than 60%. Four subjects reduced the number of errors by more than 60%. Eight out of 10 subjects showed an improvement with respect to both parameters. On median, the duration of the procedure was reduced by 46 seconds and the number of errors by 191. The statistical analysis between the two parameters showed a positive correlation. Our data suggests that training on the FESS-simulator considerably improves the performance even in inexperienced subjects, both in terms of duration and accuracy of the procedure.

Exploring planet geology through force-feedback telemanipulation from orbit.

Current space exploration roadmaps envision exploring the surface geology of celestial bodies with robots for both scientific research and in situ resource utilization. In such unstructured, poorly lit, complex, and remote environments, automation is not always possible, and some tasks, such as geological sampling, require direct teleoperation aided by force-feedback (FF). The operator would be on an orbiting spacecraft, and poor bandwidth, high latency, and packet loss from orbit to ground mean that safe, stable, and transparent interaction is a substantial technical challenge. For this scenario, a control method was developed that ensures stability at high delay without reduction in speed or loss of positioning accuracy. At the same time, a new level of safety is achieved not only through FF itself but also through an intrinsic property of the approach preventing hard impacts. On the basis of this method, a tele-exploration scenario was simulated in the Analog-1 experiment with an astronaut on the International Space Station (ISS) using a 6-degree-of-freedom (DoF) FF capable haptic input device to control a mobile robot with manipulator on Earth to collect rock samples. The 6-DoF FF telemanipulation from space was performed at a round-trip communication delay constantly between 770 and 850 milliseconds and an average packet loss of 1.27%. This experiment showcases the feasibility of a complete space exploration scenario via haptic telemanipulation under spaceflight conditions. The results underline the benefits of this control method for safe and accurate interactions and of haptic feedback in general.

Don't get tripped up: Haptic modalities alter gait characteristics during obstacle crossing.

The attentional capacity required of haptic modalities while obstacle crossing may limit their effectiveness. Therefore, this study examined the attentional demands of haptic modalities during obstacle crossing. Nineteen healthy young adults walked across a 10m laboratory floor within two modality blocks using either: 1) light touch on a railing, or 2) pulling haptic anchors. Randomly dispersed within these blocks were trials without added haptic input and verbal reaction time (VRT) tasks. VRT was compared across the three walking conditions. Gait characteristics, obstacle crossing stability, and obstacle toe clearance were compared across the three walking conditions (normal walking, light touch walking, anchored walking) and 2 VRT conditions (absence vs. presence). VRTs did not differ according to walking conditions (p>.05). Step length variability for the normal walking condition was significantly greater than for both the light touch and anchored walking conditions (p=.026). Toe clearance for the trail leg was less during light touch than normal walking (p=.020). The presence of the VRT resulted in greater toe clearance for both lead (p=.018) and trail limbs (F(2,34)=8.053, p=.011). Neither haptic modality required significantly increased attentional demand; however, light touch walking results in less obstacle toe clearance. Haptic modalities likely provide greater benefit than risk to users during obstacle crossing.

Exodex Adam-A Reconfigurable Dexterous Haptic User Interface for the Whole Hand.

Applications for dexterous robot teleoperation and immersive virtual reality are growing. Haptic user input devices need to allow the user to intuitively command and seamlessly “feel” the environment they work in, whether virtual or a remote site through an avatar. We introduce the DLR Exodex Adam, a reconfigurable, dexterous, whole-hand haptic input device. The device comprises multiple modular, three degrees of freedom (3-DOF) robotic fingers, whose placement on the device can be adjusted to optimize manipulability for different user hand sizes. Additionally, the device is mounted on a 7-DOF robot arm to increase the user’s workspace. Exodex Adam uses a front-facing interface, with robotic fingers coupled to two of the user’s fingertips, the thumb, and two points on the palm. Including the palm, as opposed to only the fingertips as is common in existing devices, enables accurate tracking of the whole hand without additional sensors such as a data glove or motion capture. By providing “whole-hand” interaction with omnidirectional force-feedback at the attachment points, we enable the user to experience the environment with the complete hand instead of only the fingertips, thus realizing deeper immersion. Interaction using Exodex Adam can range from palpation of objects and surfaces to manipulation using both power and precision grasps, all while receiving haptic feedback. This article details the concept and design of the Exodex Adam, as well as use cases where it is deployed with different command modalities. These include mixed-media interaction in a virtual environment, gesture-based telemanipulation, and robotic hand–arm teleoperation using adaptive model-mediated teleoperation. Finally, we share the insights gained during our development process and use case deployments.

Can augmented reality satisfy consumers' need for touch?

AbstractConsumers with a high autotelic need for touch tend to experience deprivation because they cannot touch products while shopping online. Augmented reality (AR) in retail allows consumers to explore products virtually as if they were present in the physical environment, except the fact that they are not touchable. This study investigates whether AR can compensate for this lack of touch or whether, on the contrary, these consumers are skeptical because they crave even more real haptic input. The results of four studies consistently show that consumers' autotelic need for touch is associated with benefits that positively impact various managerially relevant outcomes such as store and product attitudes or purchase intentions. However, the results also point to differences between expected and experienced hedonic and utilitarian benefits along the customer journey. Hedonic benefits prevail when consumers with a high need for touch actually experience AR, while they instead expect utilitarian benefits. The findings contribute to the AR marketing and online retailing literature by demonstrating that AR features can mimic touchable features of products. They also highlight the practical benefits of AR as a powerful tool in digital marketing.

The Effects of Haptic Input on Walking Balance in Individuals With Multiple Sclerosis and Controls

Research Objectives To examine sensorimotor control of walking with various haptic input modalities in people with multiple sclerosis (pwMS). Design Cross-sectional observational study. Setting Research gait laboratory. Participants Ethics approval and informed consent were obtained prior to data collection. Participants included 30 pwMS and 29 controls matched for age (±3 years) and sex. All participants were ≥ 18 years of age, and able to walk 10 m without support. Participants with conditions or injuries other than MS that could impair walking were excluded. Interventions Not applicable. Main Outcome Measures Walking without haptic input (no-touch: NT) was compared to three walking conditions with haptic input: haptic anchors (small weights on strings: HA), using a four-wheeled walker (4WW) with light touch (4WW-LT) and using a 4WW by placing weight through the handles (4WW-W). Inertial sensors (Mobility Lab, APDM) measured stride length1, gait speed2, percentage double support/stride (%DS)3, mediolateral trunk range of motion (ML-tROM)4, and lateral step variability (LSV)5. Repeated measures ANOVA examined within-and between-group differences. Results Group effects showed PwMS spent significantly greater time in %DS and had more LSV compared to controls. All participants spent less time in %DS in the 4WW-W condition compared to the other forms of haptic input. Both 4WW conditions and the haptic anchors reduced ML-tROM compared to NT. LSV was reduced with 4WW-LT and 4WW-W compared to HA and NT conditions. All participants walked significantly faster using 4WW-LT compared to all conditions. Conclusions PwMS walked with more caution and less consistent foot placement than controls. Adding only haptic input (anchors and 4WW-LT conditions) reduced ML-tROM similar to the 4WW-W condition (haptic input + mechanical support). 4WW-LT and 4WW-W demonstrated the added benefit of reducing LSV suggesting sensory information from a 4WW may improve walking balance control in pwMS; however, the reduced LSV may be due to the presence of the 4WW frame. PwMS could be encouraged to use a 4WW in different ways to support walking balance. Author(s) Disclosures Authors declare no conflict of interest. To examine sensorimotor control of walking with various haptic input modalities in people with multiple sclerosis (pwMS). Cross-sectional observational study. Research gait laboratory. Ethics approval and informed consent were obtained prior to data collection. Participants included 30 pwMS and 29 controls matched for age (±3 years) and sex. All participants were ≥ 18 years of age, and able to walk 10 m without support. Participants with conditions or injuries other than MS that could impair walking were excluded. Not applicable. Walking without haptic input (no-touch: NT) was compared to three walking conditions with haptic input: haptic anchors (small weights on strings: HA), using a four-wheeled walker (4WW) with light touch (4WW-LT) and using a 4WW by placing weight through the handles (4WW-W). Inertial sensors (Mobility Lab, APDM) measured stride length1, gait speed2, percentage double support/stride (%DS)3, mediolateral trunk range of motion (ML-tROM)4, and lateral step variability (LSV)5. Repeated measures ANOVA examined within-and between-group differences. Group effects showed PwMS spent significantly greater time in %DS and had more LSV compared to controls. All participants spent less time in %DS in the 4WW-W condition compared to the other forms of haptic input. Both 4WW conditions and the haptic anchors reduced ML-tROM compared to NT. LSV was reduced with 4WW-LT and 4WW-W compared to HA and NT conditions. All participants walked significantly faster using 4WW-LT compared to all conditions. PwMS walked with more caution and less consistent foot placement than controls. Adding only haptic input (anchors and 4WW-LT conditions) reduced ML-tROM similar to the 4WW-W condition (haptic input + mechanical support). 4WW-LT and 4WW-W demonstrated the added benefit of reducing LSV suggesting sensory information from a 4WW may improve walking balance control in pwMS; however, the reduced LSV may be due to the presence of the 4WW frame. PwMS could be encouraged to use a 4WW in different ways to support walking balance.

A Digital Twin Approach for Contextual Assistance for Surgeons During Surgical Robotics Training.

Minimally invasive robotic surgery copes with some disadvantages for the surgeon of minimally invasive surgery while preserving the advantages for the patient. Most commercially available robotic systems are telemanipulated with haptic input devices. The exploitation of the haptics channel, e.g., by means of Virtual Fixtures, would allow for an individualized enhancement of surgical performance with contextual assistance. However, it remains an open field of research as it is non-trivial to estimate the task context itself during a surgery. In contrast, surgical training allows to abstract away from a real operation and thus makes it possible to model the task accurately. The presented approach exploits this fact to parameterize Virtual Fixtures during surgical training, proposing a Shared Control Parametrization Engine that retrieves procedural context information from a Digital Twin. This approach accelerates a proficient use of the robotic system for novice surgeons by augmenting the surgeon’s performance through haptic assistance. With this our aim is to reduce the required skill level and cognitive load of a surgeon performing minimally invasive robotic surgery. A pilot study is performed on the DLR MiroSurge system to evaluate the presented approach. The participants are tasked with two benchmark scenarios of surgical training. The execution of the benchmark scenarios requires basic skills as pick, place and path following. The evaluation of the pilot study shows the promising trend that novel users profit from the haptic augmentation during training of certain tasks.

A custom virtual reality training solution for ophthalmologic surgical clinical trials

We present a summary of the development and clinical use of two custom designed high-fidelity virtual-reality simulator training platforms. This simulator development program began in 2016 to support the phase III clinical trial Archway (ClinicalTrials.gov identifier, NCT03677934) intended to evaluate the Port Delivery System (PDS) developed by Genentech Inc. and has also been used to support additional clinical trials. The two simulators address two specific ophthalmic surgical procedures required for the successful use of PDS and provide state-of-the-art physical simulation models and graphics. The simulators incorporate customized active haptic feedback input devices that approximate different hand pieces including a custom hand piece specifically designed for PDS implantation. We further describe the specific challenges of the procedure and the development of corresponding training strategies realized within the simulation platform.

Cyber-physical-system for representing a robot end effector

Programming by Demonstration (PbD) is a method to program robots through the performance of a task by humans. Most implementations are online methods that use visual or force feedback of the demonstrator. However, we developed an offline programming approach for PbD with a special input device within an Augmented Reality Environment. Therefore, this paper aims to answer how the characteristics and functionality of the end effector of a jointed-arm robot can be represented by a haptic input device in order to perform PbD. The PbD process is first carried out on a digital twin of the robot, visualized to the user in real physical space by means of augmented reality technology. The programming of the digital twin can later be transferred to the real robot. The haptic input device in this context is the main part of the Cyber-Physical-System (CPS), which enables the user to interact with the virtual robot. Therefore, the specification of the mechanical and software components of the CPS is of main importance. Within this paper, strategies for the implementation of shape and function abstraction, as well as for ensuring communication, have been worked out. The physical shape of the CPS is kept generic and is only subject to ergonomic restrictions. However, Augmented Reality overlays the physical shape with an exact digital image of the end effector used later in the process. Nevertheless, the physical characteristics of the real robot should be represented as real as possible by the CPS. Therefore, the CPS is equipped with various sensors and actuators. With the CPS it is possible to determine contact forces and to manipulate objects to a certain extent in order to teach gripping strategies to the digital twin. An operating system was developed for communication and control of the electronic components. For the validation of the functionality of the CPS an exemplary PbD process was developed, the results were analyzed and evaluated.

Influence of Haptic Sensory Input through Different Kinds of Clothing on Gait Performance

This study investigated the effects of haptic sensory input by different types of clothing worn on gait performance. Twelve healthy men performed normal and tandem gait tests with blindfolds under three different clothing conditions: (1) wearing only half tights (HT); (2) wearing a skirt-like draped outfit such as a cotton cloth wrapped around the waist and extended to the lower leg (DC); and (3) wearing a trouser-like outfit such as tracksuit bottoms (TS). Although gait speed was significantly increased in DC as compared with HT, this was not observed in TS. Missteps during tandem gait were significantly reduced with DC. In addition, DC made walking easier for individuals as compared with TS. These findings suggest that wearing a skirt-like outfit such as kilts in Scotland or the hakama in Japan may provide haptic sensory cues to enhance individuals’ perceptions of their body orientation as compared with trouser-like clothing that is in continuous contact with the legs.

User-Experience with Haptic Feedback Technologies and Text Input in Interactive Multimedia Devices.

Remote control devices are commonly used for interaction with multimedia equipment and applications (e.g., smart TVs, gaming, etc.). To improve conventional keypad-based technologies, haptic feedback and user input capabilities are being developed for enhancing the UX and providing advanced functionalities in remote control devices. Although the sensation provided by haptic feedback is similar to mechanical push buttons, the former offers much greater flexibility, due to the possibility of dynamically choosing different mechanical effects and associating different functions to each of them. However, selecting the best haptic feedback effects among the wide variety that is currently enabled by recent technologies, remains a challenge for design engineers aiming to optimise the UX. Rich interaction further requires text input capability, which greatly influences the UX. This work is a contribution towards UX evaluation of remote control devices with haptic feedback and text input. A user evaluation study of a wide variety of haptic feedback effects and text input methods is presented, considering different technologies and different number of actuators on a device. The user preferences, given by subjective evaluation scores, demonstrate that haptic feedback has undoubtedly a positive impact on the UX. Moreover, it is also shown that different levels of UX are obtained, according to the technological characteristics of the haptic actuators and how many of them are used on the device.

From Vertical Roll to .MOV File

In this article, I examine artworks from two periods in the history of media art—the 1970s and the 2010s—to demonstrate how changes in our haptic relationship to screen media shift the site of criticality in contemporary media art from disruption of electronic feedback toward an intensification and embrace of image flows that actively seek the viewer's touch and gesture. I situate video art within the shifting concept of flow in everyday media consumption, reading video art practices within a larger matrix of bodily and cultural engagement with screens. I locate touch and gesture as both themes in the content of single-channel works and components of the structure of video installation. Artists discussed include Camille Henrot, Joan Jonas, Rafael Lozano-Hemmer, Bruce Nauman, and Hito Steyerl. My analysis bridges media theory and art history with close readings of salient works of art, connecting the structure of artworks employing haptic input to shifts in the broader media ecology and the dynamic interplay of touch, image, and power under our fingertips.

The effects of light touch on gait and dynamic balance during normal and tandem walking in individuals with an incomplete spinal cord injury.

Prospective cross-sectional study OBJECTIVES: To investigate the effect of adding haptic input during walking in individuals with incomplete spinal cord injury (iSCI). Research laboratory. Participants with iSCI and age- and sex-matched able-bodied (AB) individuals walked normally (SCI n = 18, AB n = 17) and in tandem (SCI n = 12, AB n = 17). Haptic input was added through light touch on a railing. Step parameters, and mediolateral and anterior-posterior margins of stability (means and standard deviations) were calculated. Surface electromyography data were collected bilaterally from the tibialis anterior (TA), soleus (SOL), and gluteus medius (GMED) and integrated over a stride. Repeated measures ANOVAs examined within- and between-group differences (α = 0.05). Cutaneous and proprioceptive sensation of individuals with iSCI were correlated to changes in outcome measures that were affected by haptic input. When walking normally, adding haptic input decreased stride velocity, step width, stride length, MOSML, MOSML_SD, MOSAP, and MOSAP_SD, and increased GMED activity on the limb opposite the railing. During tandem walking, haptic input had no effect; however, individuals with iSCI had a larger step width SD and MOSML_SD compared with the AB group. Sensory abilities of individuals with iSCI were not correlated to any of the outcome measures that significantly changed with added haptic input. Added haptic input improved balance control during normal but not in tandem walking. Sensory abilities did not impact the use of added haptic input during walking.

Adding Light Touch While Walking in Older Adults: Biomechanical and Neuromotor Effects.

Adding haptic input may improve balance control and help prevent falls in older adults. This study examined the effects of added haptic input via light touch on a railing while walking. Participants (N = 53, 75.9 ± 7.9 years) walked normally or in tandem (heel to toe) with and without haptic input. During normal walking, adding haptic input resulted in a more cautious and variable gait pattern, reduced variability of center of mass acceleration and margin of stability, and increased muscle activity. During tandem walking, haptic input had minimal effect on step parameters, decreased lower limb muscle activity, and increased cocontraction at the ankle closest to the railing. Age was correlated with step width variability, stride length variability, stride velocity, variability of medial-lateral center of mass acceleration, and margin of stability for tandem walking. This complex picture of sensorimotor integration in older adults warrants further exploration into added haptic input during walking.